Climate change is leading to less and worse-tasting sparkling wine

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Key points:

  • Higher temperatures and more unpredictable and extreme weather events caused by climate change are posing increasing challenges for wine production, which relies on stable and specific conditions in wine-growing regions. 
  • Global wine production reached a historic low in recent years. Sparkling wine, which rose in popularity over the past 25 years, has also seen a slight decline.
  • Poor harvests and reduced sparkling wine production levels in France, Spain and Italy have been linked to climate-induced extreme weather events. 
  • Climate change is reducing the quantity of grapes, as well as impacting their quality, resulting in changes to the taste and characteristics of sparkling wine. 
  • Higher temperatures are speeding up the ripening process, but yields and flavour can also be impacted by droughts, heavy rainfall and wildfire smoke.
  • Adaptation measures, like shifting production to regions that will have more suitable climates and diversifying crops, can help reduce climate impacts on sparkling wine. 
  • However, adaptation measures can be costly and will not preserve the specific conditions sparkling wine production currently occurs under, leading to lasting changes in the flavour profiles.

Millions of people worldwide drink sparkling wine, particularly to celebrate important milestones and for special occasions, like New Year. However, sparkling wines are increasingly threatened by climate change, including the world’s most iconic labels.

Wine grapes are sensitive to their environment. Their characteristics, such as acidity, texture and flavour, depend on specific climates and a stable growing environment. Climate change is increasingly disrupting the balance of conditions like temperature, rainfall and sunlight, resulting in lower yields or altered flavour profiles.

Wine production has reached a historic low

Global wine production reached a historic low in 2024, down 4.8% from already low production in 2023, marking the lowest level in over 60 years. Production is estimated to increase slightly in 2025, but it is expected that the year will remain among the lowest production years. 

According to the International Organisation of Vine and Wine, climatic variability has been the dominant factor impacting global wine production in recent years. Impacts such as prolonged droughts, irregular rainfall, heatwaves, and unexpected frosts have reduced yields in large parts of Europe, South America, and Australia, contributing to a decline in production. The consumption of wine has also decreased, down 3.3% in 2024 compared to 2023 levels, which has also contributed to the decrease in production.

Sparkling wine has grown in popularity in recent decades. Both the export quantities and value of sparkling wine have increased by 3.7 times over the past 25 years. However, following a peak in 2021-2022, the production quantity and value of sparkling wine have decreased slightly. The export price for sparkling wine saw an annual decline of 3.7% in 2024, while volume exported saw a slight (0.3%) decline. The traded volume of sparkling wine dropped 2.5% between 2022 and 2024.

However, the change in production levels of sparkling wine varies significantly between regions. For example, production increased in Chile and South Africa between 2023 and 2024, while Spain and France saw slight declines.

Lower yields have been linked to higher wine prices

Reduced yields have led to price increases for some wine varieties. 2023 saw the average export price of wine increase to EUR 3.62 per litre, the highest ever recorded. Prices remained at this level in 2024. 

While the price of wine is influenced by various factors, there is clear evidence showing a price increase following years with climate-induced extreme weather for certain varieties of sparkling wine. 

In Spain, extreme drought in 2023 caused grape harvests in the worst-affected regions to fall by more than 45%. The following year, although rainfall improved slightly, unexpected hail and frost resulted in a similarly poor harvest. Low yields contributed to a price increase for Cava, a Spanish sparkling wine, which rose by an average of 20% internationally and 10% in Spain, according to the Cava producers’ organisation.

Grapes for prosecco, the sparkling white wine produced in northeastern Italy, are often grown on steep slopes. While ideal for producing high-quality grapes, the slopes become increasingly challenging to manage during periods of extreme rain and drought, meaning climate change poses a serious threat to this type of production. 

Analysis by UK-based think tank Energy & Climate Intelligence Unit suggests extreme weather in Italy had a knock-on effect on food imports to the UK, highlighting that in 2023 the UK imported 10 million kg less prosecco than the previous year, and the average price per kilo increased by 11%. 

In 2021, France saw the smallest harvest of Champagne since 1957 due to climate-induced extreme weather, costing the country roughly USD 2 billion in lost sales. Earlier than usual warm weather in early spring caused young leaves to unfold, which was followed by a severe frost that destroyed around a third of the harvest. However, Champagne’s status as a luxury good means that market manipulation – used to limit stocks and keep prices high – and the rising cost of living impact annual supply and demand, and climate fluctuations have less impact on final prices. 

At the same time, climate-induced reduction in the quality of premium wines may result in lower prices, as one study predicted for Napa Valley Cabernet Sauvignon from California, meaning less profit for producers.

Climate change may change the flavour of sparkling wine

Higher temperatures, unpredictable weather patterns and extreme weather events fueled by climate change also affect the flavour profile and characteristics of sparkling wines. The flavour of wine is dependent on the balance of sugar, acid and secondary components, like tannins, that develop as grapes grow and ripen. 

Too much heat accelerates ripening, causing sugar levels to spike and acids to break down, potentially leading to wines that are too alcoholic, lacking acidity or unbalanced. This shifts flavour profiles, producing cooked fruit notes over fresher aromas. Sparkling wines are particularly impacted by these changes as they are characterised by fresh flavour profiles that require lower acidity. Additionally, research suggests that the levels of alcohol in sparkling wine can affect the foam, with higher alcohol leading to a less fizzy sparkling wine.

If grapes are harvested earlier, before sugar levels increase and acids break down, grapes will not have fully developed other components, such as tannins and anthocyanins, that help to provide the layered aroma essential for quality wines. 

On average, wine-growing regions already experience almost 100 extra days each season where grapes can grow – characterised by temperatures over 10°C – since 1980. In most vineyards, harvesting has shifted two to three weeks earlier than 40 years ago due to higher temperatures. In Champagne, the harvest now takes place 20 days earlier than it did 30 years ago. Prior to 2003, no harvest began in August – since then, this has occurred eight times. 

In addition to heat, other climate change threats impact wine flavour. Droughts lead to a reduction in grape size, which can concentrate flavours and tannins, resulting in a more intense profile. In severe cases, droughts can completely halt ripening. Heavy rainfall can dilute grape flavours and promote fungal disease and uncontrolled rot, which can result in “unwanted off flavours”. 

Wildfires release smoke that can travel thousands of miles and be absorbed by the grapes, resulting in unpleasant flavours and aromas in the wine, like ashy and medicinal characteristics. Reports from Canada stated that some sparkling wine produced after the 2021 wildfires was rejected due to smoke taint. 

More extreme and unpredictable weather undermines the annual reliability that underpins premium valuations, forcing growers to adjust their practices year by year. This particularly affects the traditional character of wines that are produced in specific regions, such as Champagne and Prosecco. Shortened ripening periods and decreased water availability for the grapes used to produce the Spanish sparkling wine cava are also projected to worsen, depending on the level of warming.

Changing weather patterns could cut wine-growing regions by half

Recent studies highlight a significant shift in global wine-growing regions, driven by climate change. Globally, the number of suitable wine-growing regions could shrink by more than half if global temperatures increase by 2°C above pre-industrial levels – a threshold likely to be surpassed within this century unless significant action is taken to reduce fossil fuel emissions. 

Another paper that reviewed recent literature on climate change impacts and adaptation in wine predicts bigger impacts, finding that 70% of today’s wine-growing regions face a moderate or high risk of becoming unsuitable for growing beyond 2°C of warming. 29% of regions could see climate changes so severe that the production of premium wines would become impossible, and in a further 41% of regions viticulture would be possible only with extensive adaptation.

These impacts are particularly pronounced in southern Europe. The same review paper found that if global temperatures rise by more than 2°C, around 90% of traditional wine-growing areas in the coastal and low-lying regions of Spain, Italy, Greece and southern California could become unsuitable for producing wine in an economically viable way by the end of the century. Less than 20% of these losses could be mitigated by moving wine production to areas with higher latitudes. 

The Veneto and Friuli-Venezia Giulia regions in Italy and Catalonia, where Prosecco is produced, and the cava-producing regions in Spain, face a moderate risk of becoming unsuitable below 2°C of warming, and a high risk at 2-4°C of warming. Another study comparing European wine regions identified those in southern Europe as some of the most vulnerable. Higher-latitude regions, such as Champagne in France, are also facing significant climate-related risks.

The human cost of climate change on wine production

Harvesting grapes is a manual task that often takes place in high temperatures. Increasing temperatures are bringing forward the harvest season and accelerating ripening, resulting in shorter and earlier harvest windows. This risks exposing workers to even higher temperatures during harvesting and leads to more intense labour demands, such as working at night, which present additional safety hazards and stressors. 

The impact of heat is already taking a toll, with the deaths of four grape harvesters in the Champagne region in 2023 resulting from working in unusually hot weather. 

Working in heat means that there is a need for more time spent resting and rehydrating, reducing the hours spent in the field. A recent study estimates that labour time lost can increase by up to 2.1% for every degree of temperature increase for grape pickers. At temperatures of 36°C – which can occur regularly in some wine growing regions – up to 27% of labour is lost. A report on Australia calculated that at 2°C of global warming, there would need to be a 4% increase in labour in the horticultural industry to maintain current output.

The increase in wildfires poses an additional health threat when agricultural workers are exposed to the smoke. A recent survey in Sonoma County, known for its vineyards that are essential to California’s wine industry,  found that over 75% of agricultural workers have worked during wildfires. Over two-thirds of these workers experienced short-term health impacts, including headaches, sore throats and eye irritation. Another study in the same region used air quality monitors to show there were up to 16 days with unhealthy levels of smoke for everyone, or 27 days for sensitive individuals, during a three-month wildfire period in 2020.

Adapting sparkling wine production is expensive and has hard limits

As climate change progresses, winemakers may be forced to relocate vineyards further from the equator to maintain suitable growing conditions. Already, more sparkling wine is being produced in regions that do not traditionally produce it, such as in Germany and the UK. 

However, transplanting grape varieties from one region to another may still not yield the same distinct flavours that come from traditional wine regions, meaning the unique flavours that characterise speciality wines are at risk of disappearing. 

Plus, the traditions of wine-making are often deeply rooted in the local heritage and landscape of wine-growing regions. Such place-based cultural practices cannot simply be relocated and risk being lost if production is moved. 

Sustainability must also be considered when developing new production areas. Creating new vineyards may require converting wild land or farmland. Growing grapes can require a significant amount of water, which may not be readily available, and vineyards may compete with other uses for freshwater sources. 

Efforts to adapt viticulture through innovative approaches, such as breeding more resilient grapevine varieties and increasing crop diversity, could help maintain production in current wine regions. Irrigation systems can help address drought, although they are not necessarily sustainable in areas impacted by prolonged drought. For example, vineyard irrigation proved to be challenging in South Africa’s Cape Winelands when drought led to water sources being rationed. 

Measures to protect grapevines from weather extremes also push up costs for wineries. Electric heating cables to protect vines against harsh frost events – which are becoming more frequent – were tested in France, but can cost up to EUR 100,000 per hectare to implement. Installing shade nets to protect plants from higher solar radiation substantially increases production costs.

While these efforts may increase the sector’s resilience, they are unlikely to fully offset the impacts of climate change on wine, which is likely to fundamentally alter practices and flavours. As the climate continues to change, approaches become less effective, meaning the success of adaptation measures depends on limiting future temperature rise.

IPBES: Economic and financial systems must evolve to protect biodiversity and support transformative change

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Key points:

  • The IPBES Nexus assessment – a first-of-its-kind scientific assessment from an intergovernmental body on the interlinkages between biodiversity, climate, health, water and food – has significant findings on the risks to the financial and economic systems that these connections pose.
  • In parallel, the Transformative Change Assessment provides insights into the shifts in views, structures and practices needed for deliberate transformative change for a just and sustainable world. 
  • Financial and economic systems need nature to function. Around USD 58 trillion – or over half of the world’s GDP in 2023 – comes from sectors that are moderately or highly dependent on nature, meaning that the increasing degradation of natural resources is putting the way our economy functions at risk. 
  • The negative externalities arising from the fossil fuel, agriculture and fisheries sectors are estimated at USD 10 trillion–25 trillion annually, severely impacting biodiversity, water, food security, health and climate change.
  • In contrast, investment in biodiversity conservation remains critically low, with only between USD 135 billion and USD 200 billion directed toward improving the status of nature annually from both public and private sources. To tackle the biodiversity funding gap, the financial needs are estimated in the range of USD 300 billion–1 trillion per year.
  • To protect nature and biodiversity and address the risks posed by climate change, reforms in economic and financial systems are necessary. These will include increasing financial flows to biodiversity, addressing debt crises, fostering greater involvement of the private sector, pricing environmental degradation, reforming harmful subsidies and decreasing inequalities.

The Nexus Assessment, released by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES, sometimes called the IPCC for biodiversity) on December 17, 2024, is the most ambitious scientific assessment ever undertaken of the interlinkages between biodiversity loss, water availability and quality, food insecurity, health risks and climate change. At the same time, IPBES also produced the Transformative Change Assessment, which provides insights into the underlying causes of biodiversity loss and the shifts needed to affect deliberate transformative change for a just and sustainable world. The release of both reports followed negotiations between IPBES’ 147 member states after three years of work by experts and multiple consultations with Indigenous Peoples and practitioners.

The assessments make it clear that economies face substantial risk due to our high dependence on biodiversity and nature – which has largely been a blind spot in the global finance system. Scientists agreed that over half of the world’s GDP – USD 58 trillion in 2023 – is generated in sectors that are moderately to highly dependent on nature, exposing these economic activities to risks from biodiversity loss and ecosystem collapse. 

One of the key elements in both reports is the role of economic and financial systems, particularly public and private spending, in supporting or hindering transformative change and the challenges and crises of biodiversity loss, water availability and quality, food insecurity, health risks and climate change (also referred to as the nexus elements). This briefing draws on the findings to summarise how economic and financial systems impact the interlinkages between the nexus elements, and highlights the role finance and economic policy decisions play in securing deliberate transformative change for a just and sustainable world.  

The causes of the breakdown: how economic and financial systems contribute to erosion of biodiversity, water, food, health and climate

The Nexus and Transformative Change reports make clear that economic and financial activity is actively contributing to the deterioration of biodiversity and nature, with the Nexus Assessment stating that: “Dominant economic systems can result in unsustainable and inequitable economic growth”. 

Current policies and international agreements fail to address the substantial negative externalities and can contribute to harming nature. Societal, economic and policy decisions that focus on short-term financial returns without accounting for the broader costs to nature and other nexus elements lead to unequal outcomes for human well-being. For example, the Transformative Change Assessment points out that current market growth-driven paradigms, embodied by metrics such as Gross Domestic Product, limit our definition of development, ignoring other economic, social (including cultural) and environmental dimensions.

More than half of the global population lives in areas facing significant pressure on one or more nexus elements. These impacts are felt disproportionately by those living in low-income countries and small island developing states, as well as by marginalised groups and Indigenous Peoples. While different countries experience the economic impacts of biodiversity loss to varying degrees, developing countries face higher relative impacts due to financial barriers such as high debt burdens that make it more difficult for them to mobilise financial flows. 

The two reports put a value on the impact of economic and financial systems on biodiversity and other nexus elements:1Some figures from the Nexus Assessment and the Transformative Change Assessment vary slightly due to different calculation methodologies and definitions in the underlying literature upon which they are based. Multiple analyses coming to similar results supports the validity of the conclusions.

  • The Nexus Assessment calculates that USD 7 trillion per year is invested in economic activities that damage biodiversity. Of this, private sector financial flows directly harmful to biodiversity total about USD 5.3 trillion per year and public flows are around USD 1.7 trillion. 
  • The Transformative Change Assessment collates global public explicit subsidies to sectors driving nature’s decline, finding they stood between USD 1.4 trillion and USD 3.3 trillion in 2023. Agriculture received USD 520 billion-851 billion and fossil fuels received USD 440 billion-1.26 trillion.
  • The negative externalities arising from the fossil fuel, agriculture and fisheries sectors are estimated at around USD 10 trillion–25 trillion annually, according to figures in both reports, illustrating how severely consumption and production in these sectors affect biodiversity, water, food, health and climate change. 
  • Illegal resource extraction globally, including in the wildlife, timber and fish trades, is valued at USD 100 billion–300 billion or more each year, per Nexus Assessment figures.

In contrast to the trillions of dollars invested in or subsiding harm to the nexus elements, funding for biodiversity sits between USD 135 billion and USD 200 billion according to the Transformative Change Assessment and the Nexus Assessment (see Figure 1).

Figure 1: Financial flows harming biodiversity vastly outweigh funding to improve it
Source: Transformative Change Assessment Figure SPM. 7

Transforming the economic and financial system to preserve nature

Both reports lay out the importance of taking action to transform economic and financial systems to conserve and restore nature. Taking action now could have a business opportunity value of over USD 10 trillion and support 395 million jobs by 2030, according to a recent study cited in the Transformative Change Assessment. The reports outline a number of such actions, several of which are described below.

Increase financial flows to biodiversity, particularly to Indigenous Peoples and local communities

The current economic system fails to comprehensively capture biodiversity’s full value and relies on incentives that only consider how nature benefits humans directly, for example through food and water provision. Despite nature’s role in underpinning economic activity, investment in biodiversity conservation remains low. Only around USD 153 billion-200 billion in annual expenditure is directed toward biodiversity improvement efforts, according to both reports.

This funding is significantly lower than financial flows that cause direct harm to nature. According to the Nexus Assessment, bridging this gap requires additional resources estimated in the range of USD 300 billion–1 trillion per year,2The Transformative Change Assessment puts the financing gap at USD 598 billion to 824 billion, showing that these estimates are highly consensual if not exactly identical. with at least USD 4 trillion needed to meet the Sustainable Development Goals most connected to water, food, health and climate. Promising mechanisms such as green bonds or blue bonds remain underutilised, and other options such as payments for ecosystem services mobilise only USD 42 billion per year from both public and private sources, according to the Nexus Assessment. Likewise, establishing sustainability as a central tax principle and reducing tax avoidance can help generate funds for biodiversity.

Indigenous Peoples frequently experience degraded biodiversity, water, food, health and climate, have difficulty accessing financing and are excluded from decision-making processes. Despite this, Indigenous Peoples and local communities make successful contributions to biodiversity conservation and the sustainable management of resources, highlighting the importance of recognising their rights and roles in decision-making processes. Recognising and supporting Indigenous-led conservation activities and food system management leads to significant benefits across the nexus elements. Successful conservation projects must involve Indigenous Peoples and local communities in all steps of the process, including co-decision and governance. Yet, only a small fraction of biodiversity finance is spent in developing countries, and Indigenous Peoples face challenges accessing funding and finance.

Reform debt to enable highly indebted biodiverse countries to protect nature

Low- and middle-income countries are most likely to feel the economic effects of biodiversity loss and the degradation of water, climate, food, and health. Developing countries also face significant barriers in accessing finance to protect nature and address climate change. Reforms to the financial system, including addressing debt crises, taking into account the need to enable just and equitable transitions and tackling the cost of finance connected to perceived investment risks, could help these countries access adequate and affordable financing.

Foster greater involvement from the private sector

Private finance for biodiversity is lacking, with the private sector accounting for only 17% of investments in nature-based solutions, according to the Transformative Change Assessment. Additionally, what private finance there is gets skewed towards developed countries, with just 5% allocated to least-developed and other low-income countries, according to the Nexus Assessment. 

One option to incentivise private investment in biodiversity is to make nature a key financial factor for companies. Furthermore, coalitions with multiple actors, including the private sector, are more effective at creating transformative change in general, showing that they have a role to play beyond simply providing finance.

Put an accurate price on environmental degradation

The current economic and financial systems fail to account for negative externalities from the most polluting sectors, with environmental impacts costing trillions of dollars per year, according to figures from both reports. Different ways to internalise these costs – to ensure they are included in the cost of doing business and reflected in the final price of products and services – could be employed more widely. Examples include water pricing and natural capital accounting, which helps identify and value natural assets, and the application of taxes or fines on environmentally harmful activities.

Eliminate, phase out or reform subsidies to move towards more sustainable practices

Governments spend USD 1.7 trillion a year on subsidies that incentivise biodiversity-damaging activities, according to the Nexus Assessment, and these subsidies have increased by 55% since 2021, according to the Transformative Change Assessment. By eliminating, phasing out or reforming public subsidies that damage biodiversity, water, food, health or climate, business models could be moved towards sustainable practices, taking into account the differing needs of developing countries. For example, some agricultural subsidies support unsustainable food production practices and undermine the livelihoods of small-scale producers. These subsidies could be eliminated, phased out or reformed to better support the consumption and production of sustainable food.

Decrease inequalities to address underlying causes of biodiversity loss

The concentration of wealth and power is an underlying cause of biodiversity loss. These differences in wealth and power exist between countries and also within countries, with the wealthiest segment of the global population consuming and using more resources. Because of these unsustainable practices, the rich drive biodiversity loss both locally and globally. Current power dynamics create structural inequalities within economic and financial systems that act to increase distributional inequity and make justice more difficult. In response to these challenges, the Transformative Change Assessment points to revising multilateral cooperation agreements and trade policies to help overcome global inequalities and create coherent governance for just and sustainable development.

  • 1
    Some figures from the Nexus Assessment and the Transformative Change Assessment vary slightly due to different calculation methodologies and definitions in the underlying literature upon which they are based. Multiple analyses coming to similar results supports the validity of the conclusions.
  • 2
    The Transformative Change Assessment puts the financing gap at USD 598 billion to 824 billion, showing that these estimates are highly consensual if not exactly identical.

Net-zero progress overblown by inconsistencies in land carbon accounting

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Key points:

  • Nationally Determined Contributions (NDCs) – which outline national governments’ commitments to emissions reduction – account for land-based carbon removal using different methods to the IPCC. 
  • When the methods are harmonised, NDCs reduce the budget for limiting warming within Paris Agreement goals by 15-18%, equivalent to bringing forward the deadline for net zero by five to seven years. 
  • This means governments need to set far more ambitious mitigation targets to achieve net zero as defined by the IPCC, than covered by their current methods.
  • Differences in how emissions are reported from managed and unmanaged land in NDCs compared to the IPCC introduces opportunities for bias or misrepresentation, obscuring countries’ true climate impacts.
  • The amount of land designated for land-based removals in NDC pledges – about 1 billion hectares or the equivalent of around two-thirds of global arable land – is also impossible without complex trade-offs for food security, biodiversity and human livelihoods.
  • IPCC models give unrealistically optimistic estimates of land-based removal potential because they don’t consider land availability constraints, conflicts and human rights issues, or the erosion of land carbon sinks.
  • By comparison, a recent analysis modelling the social and ecological risks of land-based carbon removal potentially reduces the amount of land available for carbon removal by up to 79% compared to IPCC estimates.   
  • This discrepancy suggests that status quo estimates of land-based carbon removal used to inform global and national climate ambition may be overblown and misleading.

Emissions reduction in NDCs

Under the Paris Agreement, adopted in 2015, countries around the world agreed to submit climate action plans called Nationally Determined Contributions (NDCs) every five years starting in 2020 to address greenhouse gas emissions.1Each new NDC submitted needs to be more ambitious than the last. NDCs translate global agreements into specific national targets and are the key mechanism for countries to show their commitment to reducing emissions – through, for example, phasing out fossil fuels, deploying renewable energy, decarbonising industries and electrifying transport.

Another approach to reducing emissions involves harnessing the ability of landscapes to capture and store carbon – a greenhouse gas inventory sector referred to as land use, land-use change, and forestry (LULUCF) by the Intergovernmental Panel on Climate Change (IPCC).2LULUCF excludes non-carbon-dioxide agricultural emissions, such as methane from livestock. Natural landscapes around the world store significant amounts of carbon in plants and soil – global forests absorb an average of 7.6 billion metric tonnes of carbon dioxide per year, equivalent to around one and a half times the annual emissions of the US. 

In the LULUCF component of their NDCs, countries pledge to plant new forests (afforestation), restore degraded forests (reforestation), protect existing forests and implement sustainable forest management and soil conservation techniques. To a much lesser degree, they also project the use of bioenergy with carbon capture and storage (BECCS), whereby trees, crops or algae will, in theory, be grown to capture carbon dioxide from the atmosphere and then converted into energy, such as biofuels, with the emissions stored below ground.

These forms of carbon dioxide removal are appealing to governments and industries because they don’t necessitate immediate, large-scale changes to a country’s industrial and energy sectors.  However, although most IPCC pathways that aim to limit warming to Paris Agreement targets of 1.5°C or 2°C include carbon sequestration in land sinks, enhancing these sinks alone is insufficient to achieve the necessary carbon reductions. Ambitious and timely NDC commitments this decade could close the emissions gap needed to keep temperatures within targets but require a rapid shift away from traditional fossil fuels in addition to land-based removal. 

Due to several scientific and political reasons outlined below, the potential contribution of land carbon sequestration to emissions reductions is significantly overestimated in NDCs and scientific models. This overestimation renders the commitments outlined in NDCs unrealistic and endangers the goals of the Paris Agreement. While several publications have explored this issue, no comprehensive, easy-to-read resource has been created to synthesise the findings. The goal of this briefing is to provide a concise summary of the various reasons NDCs disproportionately rely on land for carbon removal and to outline the potential implications for the Paris Agreement.

Land carbon fluxes are the most uncertain component of the global carbon budget

Countries annually report their progress on the emissions reductions pledged in their NDCs through National Greenhouse Gas Inventories (NGHGIs), following guidelines established by the United Nations Framework Convention on Climate Change (UNFCCC). 

Collective progress towards the Paris Agreement goals is assessed every five years in the Global Stocktake, which provides benchmarks for countries for their NDC submissions. If NDCs are insufficient or lack ambition, there is a significant risk that the world will exceed the Global Carbon Budget – the total amount of carbon dioxide that can be emitted while keeping within global temperature targets, leading to temperature increases beyond the targets agreed upon in the Paris Agreement.

Because of the complex interactions of various human-driven effects on greenhouse gas fluxes from land – such as deforestation for agriculture – land carbon fluxes are the most uncertain component of the global carbon budget. At the national level, accurately tracking changes in forests and other land uses is also challenging due to variations in the quality and scope of land-use data, different reporting methods used, and difficulties in separating the influence of humans and climate on the environment as well as in reporting carbon movements in different ecosystems, with estimates relying significantly on simplified models. This means that estimates of emissions from LULUCF are less precise than those from fossil fuels, which are grounded in empirical data.

As a result, the Paris Agreement allows flexibility for countries to determine how they account for emissions and removals from the LULUCF sector, such as the use of different accounting and monitoring methods or different definitions of land-use types in their climate targets. In addition, developing countries are encouraged to gradually adopt economy-wide emission reduction targets depending on their economic and developmental needs. In comparison, developed countries are required to specify a specific, measurable and economy-wide reduction in overall emissions – for example, a 40% emissions reduction compared to 1990 levels.

NDC net-zero may not mean net-zero global emissions

The use of different carbon accounting methods for land-based removal between NDCs and model-based methods, such as those used by the IPCC, makes it hard to measure the emissions and temperature outcomes of current national commitments under the Paris Agreement. 

While both NGHGIs and the models used by the IPCC to assess the pathways necessary to achieve specific climate targets aim to identify greenhouse gas fluxes from land, they differ in how they account for the role of human activity in these fluxes. This affects the extent to which each approach attributes these fluxes to a country’s mitigation efforts.3One outcome is that estimates of land-use change due to afforestation or reforestation are in close agreement between NGHGIs and IPCC models, but differ for managed forests.

This is especially problematic for countries that rely heavily on the land sector and forest management to achieve their NDCs, leading to over- or under-estimating true emissions and creating inconsistencies between national inventories and the global carbon budget.

A recent analysis illustrated how current NGHGIs for NDCs can make national emissions appear lower than the method applied by the IPCC in assessing alignment with the Paris Agreement. It concluded that once the methods are harmonised – such as by adjusting fluxes from land use – our overall carbon budget is reduced by 15-18%, which is equivalent to bringing forward the deadline for net zero up by five to seven years. What this means is that governments need to set far more ambitious mitigation targets to achieve net zero, as defined by the IPCC.

Unmanaged land is a blind spot in carbon accounting

Discrepancies in the LULUCF emissions estimates between IPCC models and NDCs arise partly because countries are not required to report emissions from unmanaged land – such as emissions from wildfires in remote forests where human intervention is minimal or absent – as these are considered natural rather than human-caused emissions. This has resulted in some highly forested countries designating large areas of forest as unmanaged. But as emissions are still released from these unmanaged areas, excluding them leads to an incomplete picture of the carbon cycle and a country’s total emissions.

This has introduced opportunities for bias or misrepresentation. For example, Canada does not include emissions from forest wildfires in its inventory, as around 34% of its forests are classified as ‘unmanaged’. This means that emissions from natural disturbances, such as wildfires, in these forests are not accounted for.4The Canadian government does not have a database for the net carbon flux in unmanaged lands in the country, making it difficult to track carbon emissions and evaluate whether Canada’s landmass is sequestering enough carbon to offset its emissions. Additionally, fires within its managed forests are also classified as natural disturbances rather than human-caused disturbances, and so are also excluded from the inventory.

This oversight leaves significant emissions unaccounted for, obscuring Canada’s true climate impact. Around 114 million metric tonnes of emissions was excluded per year from its inventory between 2005 and 2021 – equivalent to around half the total carbon dioxide emissions from gas in Canada in 2023.5This is compounded by the fact that Canada classifies removals from mature forests as human-caused. In 2023, a year of record-breaking wildfires, natural disturbances released an estimated 640 million metric tonnes of carbon from Canada’s forests, which is more than Canada’s carbon dioxide emissions from fossil fuels in 2022.

Managed land can lead to overestimates of climate progress 

Flexible guidelines also mean that there is variation in what constitutes managed and unmanaged land. Under the Kyoto Protocol adopted in 1997, countries agreed to count greenhouse gas emissions and removals from land activities towards their climate targets only if they result from direct human actions. However, the IPCC later noted that as human activities and environmental changes are closely linked, they are not practical to separate in greenhouse gas inventories – for example, forest loss from both logging and climate-induced drought. Therefore, ‘managed land’ was introduced as a proxy for human effects in NDC guidelines, with all greenhouse gas fluxes occurring on managed land being counted regardless of whether they are driven by humans or the environment. This is not a feature of the IPCC’s models that are used for estimating carbon fluxes, which clearly distinguish between emissions from managed and unmanaged forests. 

This means that countries can classify natural forests as managed land in their NGHGIs, enabling them to report natural carbon removal as emissions reductions. Including natural land as managed land can also give a misleading picture of a country’s actual climate efforts by overestimating carbon removals and making progress seem greater than it is. This is further aggravated by the fact that some countries – particularly those that are afforded flexibility in emissions accounting – also report implausibly high forest sinks, have incomplete assessments or have inconsistent estimates across reports. Some forest-dense countries are claiming credit for the carbon that their unmanaged forests are sequestering, using this as a means to justify fossil fuel extraction while also making net-zero claims.

Land-based removal plans are unrealistic

The lack of stringent accounting guidelines has led to a significant over-allocation of land for carbon removal in NDC pledges, beyond what is technically feasible or safe. The Land Gap Report calculated that there is about 1 billion hectares of land for land-based carbon removal included in NDC pledges to 2060 – equivalent to around two-thirds of the world’s arable land and a land area bigger than China. Such large-scale commitments would be impossible without catastrophic impacts, including the displacement of food production and threats to biodiversity. 

Pledges for land-based removal in NDCs rely heavily on planting new forests or plantations, with about half of the land proposed for carbon removal in NDCs requiring changes in present land use. Land-use change is already the biggest driver of biodiversity loss, which is essential for ecosystem resilience and the provision of ecosystem services such as food and water security and carbon sequestration.6Agricultural land is already under significant pressure from rising global food demand, expanding populations and the need to balance land use with biodiversity conservation and climate mitigation efforts. A 2022 analysis estimated that afforestation and bioenergy production could place an additional 41.9 million people at risk of hunger by 2050 due to higher food prices and displacement of agricultural land

In addition to the risks around increased competition for land use, estimates suggest that the ‘safe limit’ for expanding agriculture has already been passed, resulting in ecosystem degradation. Figure 1 shows that global cropland already exceeds the planetary boundary for sustainable land use, with land-use changes in pledges and current and projected BECCS projects adding nearly an extra two-thirds to the current land-use change area. There is very little land left that can be used for carbon dioxide removal without complex trade-offs. To be genuinely effective, carbon removals plans need to factor in ecological limits and support biodiversity.

Figure 1. Land for mitigation crosses planetary boundary thresholds
Source: The Land Gap Report, 2022.

Even if the estimates of removal potential from land in NDCs were technically feasible, a 2023 analysis calculated that current NDCs are insufficient for meeting Paris Agreement targets – actions outlined in NDCs are due to result in warming of 2.5-2.9°C by 2100.

Limitations in IPCC models of future land carbon removal 

While NDCs focus on near-term actions to reduce greenhouse gas emissions, Integrated Assessment Models (IAMs) used by the IPCC project long-term scenarios for achieving climate goals. IAMs assess the interactions between climate, energy, land use and economic systems to understand the long-term implications of different policy choices and emissions trajectories, offering different pathways that illustrate how various strategies can achieve climate targets. IPCC pathways offer a framework for countries to set their emissions reduction targets and to align their NDCs to demonstrate their commitment to international climate agreements.

However, recent research argues that the methodologies in IPCC models are over-relying on land-based removal by building in assumptions about land use that are unrealistic. The models do not reflect real-world conditions such as land availability, lack nuance by failing to capture the complexities of human systems and ecosystems, and expose vulnerable communities to avoidable risks. As IPCC reports are the primary mechanism informing the UNFCCC, inappropriate models have the potential to lead to misguided policies and ineffective climate action, ultimately hindering efforts to reduce greenhouse gas emissions and meet international climate goals.

Hidden assumptions mean models over-rely on land

A key challenge with the representation of land-based carbon removal in IAMs is the assumption that significant emissions generated in the near term will be offset in the distant future through decades of land-based removal. 

Because of their emphasis on cost-effectiveness, least-cost pathways and supply-side technologies, IAMs often assume that large-scale BECCS and afforestation projects can be implemented easily, without considering competing demands for land. This leads to overestimations of the amount of land available for future carbon removal in the LULUCF sector. To demonstrate this, a 2018 study assessed the rate at which land uses change in IAMs and found that in scenarios limiting warming to 2°C by 2100, cropland for BECCS is projected to expand by 8.8 million hectares per year. This expansion rate is more than three times as fast as the historical expansion of soybean, which is currently the fastest-growing commodity crop and a significant driver of deforestation in the Amazon. 

IAMs also have idealised assumptions that do not fully consider the technical, social and economic barriers to scaling up such efforts, such as land tenure issues, governance challenges, the potential for conflict over land use​ and human rights issues, including rights to food, water and a healthy environment. 

IAMs are built on assumptions of ‘empty land’ that do not consider nomadic or Indigenous lifestyles or non-forest ecosystems, such as savannas, and also broadly assume that forests can be converted to cropland for bioenergy. BECCS only features in the NDCs of seven countries, totalling 80 million hectares of land, but it is much more prominent in modelled IPCC pathways, with a median land demand of 199 million hectares (ranging from 56 million to 482 million hectares) in 1.5°C-consistent pathways. However, given such a significant land demand for BECCS from a small number of countries in current NDCs, a land demand of 199 million hectares in future pathways is likely to be an underestimate if BECCS becomes as widespread as in modelled pathways.

The models have also been criticised by researchers for being opaque, with specific value judgments about the future buried in the mathematics of the model. By assuming that the financial costs of mitigation technologies will fall in the future – through applying a high discount rate in the model – solutions like BECCS, which has not yet been proven to work at scale, can appear more cost-effective than proven, readily implementable actions. As BECCS is considered ‘carbon neutral’ in the models, many IAMs also favour large-scale BECCS over renewable technologies to meet the requirements of one of the more ambitious climate pathways that assumes significant reductions in greenhouse gas emissions.7The RCP 2.6 emissions pathway in the IPCC’s Sixth Assessment Report.

A 2024 analysis found that a high discount rate in IAM models favours high overshoot scenarios – where global average temperatures temporarily exceed a warming target before dropping back down to, or below, the target in the future – rather than scenarios that would mitigate long-term warming effects. This is because of the short timescale over which economic adaptation is assessed in the models. These high overshoot scenarios result in a heavy reliance on land-based carbon dioxide removal in the future as emissions are not reduced fast enough to limit warming. Overshoot is estimated to be cheaper than longer-term solutions and is therefore favoured by the models. However, overshoot comes with various risks and uncertainties, such as species extinction and ecosystem collapse, and has potentially irreversible consequences. Overshoot also raises moral concerns, as climate-related impacts disproportionately affect vulnerable populations, especially in low-income countries.

Reliance on land carbon removal raises sustainability risks

A recent analysis proposed thresholds for land-based sequestration that account for social and ecological risks, thereby developing realistic and sustainable estimates for land-based CDR while accounting for environmental and resource limits (Table 1).​ The analysis estimates that the sustainable potential of LULUCF measures for carbon removal, including limited reforestation, forest restoration, reduced forest harvest, agroforestry and silvopasture, and BECCS is  3.3 billion-3.8 billion tonnes per year.8Values obtained from Supplementary Table S1 in the report.

The study finds that at high sustainability risk – the point at which multiple ecological and social sustainability limits are likely to be overstepped with potentially irreversible consequences – the value is 6.4 billion tonnes per year. These estimates of sustainable – and hence feasible – removal potential are more conservative than the average estimates in the IPCC’s Sixth Assessment Report – 15.6 billion metric tonnes of carbon dioxide per year between 2020 and 2050 for BECCS, forest and ecosystem protection, restoration and management, and agroforestry, as well as the Emissions Gap Report which included estimates of 5.9 billion tonnes per year by 2030 and 8.4 billion tonnes by 2035 for forestry-related land management,9Values obtained from Table 6.2: Sectoral mitigation potentials in 2030 and 2035. and the State of CDR Report at 7 billion-9 billion metric tonnes by 2050 from forestry-related removal, BECCS, ecosystem restoration and novel technologies such as direct air capture. Compared to IPCC estimates, a low sustainability risk scenario potentially reduces land available for carbon removal by around 79%.10This is a rough calculation assuming a direct comparison between land-use footprint in the IPCC technical mitigation potential and the analysis in Deprez et al. (2024) and was calculated as the difference between the IPCC estimates of 15.6 billion metric tonnes and the lower sustainability risk estimate of 3.3 billion tonnes.

Overall, the greatest risks are linked to scenarios with slower emission reductions and higher reliance on future carbon removal technologies. This highlights the need to reduce emissions quickly and significantly and not rely on future carbon removals – including from land – in order to avoid the worst outcomes.

Table 1. Sustainability risks for land-based carbon dioxide removal for the five IPCC Illustrative Mitigation Pathways compatible with the Paris Agreement.
Data source: Sustainability limits needed for CO2 removal, 2024.  
A/R refers to afforestation/reforestation. BECCS & A/R larger footprint assumes a low capture rate and conversion efficiency, while BECCS & A/R medium footprint assumes a medium capture rate and conversion efficiency.
Models do not account for land’s declining ability to store carbon

As IAMs are global in scale, their assumptions are simplified and generalised, and therefore they can miss key local dynamics, leading to ill-suited projections at the regional level​.11The IPCC recommends that these models are interpreted in the context of their assumptions. IAMs often oversimplify ecosystems, which do not always behave linearly in response to human activities or climate change. For instance, land-use changes can trigger feedback loops that are difficult to capture accurately in simplified models. A 2024 analysis found that IAMs tend to underestimate the risks associated with the interaction between wildfire disturbances and climate change, particularly regarding their impact on the ability of forests to sequester carbon, risking an overly-optimistic estimate of how much carbon forests can remove and store, and inaccurate predictions of future emissions​.

This is significant because land and ocean sinks are increasingly absorbing less carbon with rising temperatures. In higher emissions scenarios, the interaction between climate change and the carbon cycle becomes more uncertain due to the risk of positive feedback loops – such as forest fires and permafrost thaw – amplifying climate change impacts. These types of ecosystem responses are not fully integrated into models simply because of their sheer complexity. While models have tended to predict a slow erosion of natural carbon sinks over the next 100 years or so, other estimates suggest that the impact from feedback loops is happening much sooner than anticipated.

  • 1
    Each new NDC submitted needs to be more ambitious than the last.
  • 2
    LULUCF excludes non-carbon-dioxide agricultural emissions, such as methane from livestock.
  • 3
    One outcome is that estimates of land-use change due to afforestation or reforestation are in close agreement between NGHGIs and IPCC models, but differ for managed forests.
  • 4
    The Canadian government does not have a database for the net carbon flux in unmanaged lands in the country, making it difficult to track carbon emissions and evaluate whether Canada’s landmass is sequestering enough carbon to offset its emissions.
  • 5
    This is compounded by the fact that Canada classifies removals from mature forests as human-caused.
  • 6
    Agricultural land is already under significant pressure from rising global food demand, expanding populations and the need to balance land use with biodiversity conservation and climate mitigation efforts. A 2022 analysis estimated that afforestation and bioenergy production could place an additional 41.9 million people at risk of hunger by 2050 due to higher food prices and displacement of agricultural land
  • 7
    The RCP 2.6 emissions pathway in the IPCC’s Sixth Assessment Report.
  • 8
    Values obtained from Supplementary Table S1 in the report.
  • 9
    Values obtained from Table 6.2: Sectoral mitigation potentials in 2030 and 2035.
  • 10
    This is a rough calculation assuming a direct comparison between land-use footprint in the IPCC technical mitigation potential and the analysis in Deprez et al. (2024) and was calculated as the difference between the IPCC estimates of 15.6 billion metric tonnes and the lower sustainability risk estimate of 3.3 billion tonnes.
  • 11
    The IPCC recommends that these models are interpreted in the context of their assumptions.

Agroecological practices support climate change resilience

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Key points:

  • A number of meta-analyses, reviews and studies have compared the environmental and economic outcomes of agroecological practices compared to conventional agricultural practices.
  • There is a strong empirical evidence base for agroecology-aligned practices in supporting climate change adaptation, mitigation and resilience.
  • Benefits from agroecology practices include improved grain yields with fewer inputs, greater biodiversity, improved soil health and water security, and enhanced carbon sequestration.
  • Agroecology practices also reduce the need for pesticides and fossil-fuel-intensive synthetic fertilisers, reducing environmental risks as well as economic and health burdens for farmers.
  • Studies have also found that the concurrent application of more than one agroecological practice increases beneficial outcomes, with some finding that the positive outcomes increase with time.
  • While a number of agroecological benefits have been identified, the impacts are highly context-specific. Approaches will need to be tailored to the conditions of the region, ecosystem or farm.

What the science tells us about the benefits of agroecological practices

Agroecology emphasises the use of natural processes and resources to create sustainable and resilient agricultural systems. It is a response to modern intensive agricultural systems that focus on maximising production, sometimes at the expense of ecological and environmental health. A number of common agricultural practices are aligned with agroecology. For example, planting legumes alongside other crops – a centuries-old practice that is still widely used today – can improve soil fertility and water infiltration into the soil, thereby enhancing the health of the soil ecosystem and ultimately leading to increased crop yields.

Critics question the ability of agroecology to meet food security needs in a world that is increasingly at risk of climate change-induced threats that place pressure on natural systems, humans and economies.1David Zaruk, ‘Is Agroecology a Solution or an Agenda?’, Outlook on Agriculture 52, no. 3 (2023), https://doi.org/10.1177/00307270231191807. However, scientific support does exist for agroecological practices in enhancing resilience through energy efficiency, ecosystem services, food security and economic outcomes.

Through assessing more than 30 meta-analyses, seven second-order meta-analyses, and several reviews and field trials, this article summarises some of the ways by which agroecology-aligned practices can contribute to climate change resilience.

Yield and economic benefits with fewer inputs and emissions

One of the core tenets of agroecology is to reduce reliance on external inputs, such as synthetic fertilisers, pesticides and herbicides, in favour of practices that support biodiversity and soil health. As synthetic fertilisers are energy-intensive to produce and are typically made using fossil fuels, limiting their use can help reduce greenhouse gas emissions from agriculture. Synthetic fertilisers also contribute to nitrous oxide emissions – a potent greenhouse gas with significant ozone-depleting potential – once applied to the soil, with one study estimating that two thirds of emissions from synthetic fertilisers occur once they have been applied to the field.2Yunhu Gao and André Cabrera Serrenho, ‘Greenhouse Gas Emissions from Nitrogen Fertilizers Could Be Reduced by up to One-Fifth of Current Levels by 2050 with Combined Interventions’, Nature Food 4 (2023): 170–78, https://doi.org/10.1038/s43016-023-00698-w. Fertiliser application in conventional agriculture is excessive – nitrogen and phosphorus inputs are 60% and 48% higher than what major crops can use to grow – marking a clear space for agroecology-aligned principles in reducing emissions.3Paul C. West et al., ‘Leverage Points for Improving Global Food Security and the Environment’, Science 345, no. 6194 (2014): 326, https://doi.org/10.1126/science.1246067.

Excessive chemical fertiliser application does not necessarily improve yields. For example, larger quantities of nitrogen or phosphorus fertiliser application did not have a positive effect on grain crop yields in a meta-analysis of more than 70 smallholder farms based in sub-Saharan Africa.4Marc Corbeels et al., ‘Limits of Conservation Agriculture to Overcome Low Crop Yields in Sub-Saharan Africa’, Nature Food 1, no. 7 (2020): 449, https://doi.org/10.1038/s43016-020-0114-x. Rather, a positive effect was only noted at the lowest phosphorus fertiliser application rates of 0–20 kg P ha−1 and 20–40 kg P ha−1, while increasing the amount of fertiliser had negative effects on yield. Other estimates suggest that nitrogen and phosphorus application could be reduced by up to 29% and 22%, respectively, while maintaining current yields of wheat, rice and maize.5West et al., ‘Leverage Points for Improving Global Food Security and the Environment’, 326. Reduced fertiliser inputs in agroecological systems also alleviate a major economic expense for farmers.6David Weisberger, Virginia Nichols, and Matt Liebman, ‘Does Diversifying Crop Rotations Suppress Weeds? A Meta-Analysis’, ed. Upendra M. Sainju, PLOS ONE 14, no. 7 (2019): e0219847, https://doi.org/10.1371/journal.pone.0219847. However, it is important to note that in certain areas, such as those with historically low fertiliser input levels, input reduction may not be appropriate.7Gatien N Falconnier et al., ‘The Input Reduction Principle of Agroecology Is Wrong When It Comes to Mineral Fertilizer Use in Sub-Saharan Africa’, Outlook on Agriculture 52, no. 3 (2023): 311–26, https://doi.org/10.1177/00307270231199795.

Shifting cropland systems towards agroforestry systems – whereby trees or shrubs are planted alongside crops or livestock – is a viable solution to addressing the leaky nitrogen cycle – whereby excess nitrogen is leaked into the environment or atmosphere, leading to emissions and water pollution, biodiversity loss and habitat degradation.8Ahmed S. Elrys et al., ‘Expanding Agroforestry Can Increase Nitrate Retention and Mitigate the Global Impact of a Leaky Nitrogen Cycle in Croplands’, Nature Food 4, no. 1 (2022): 109–21, https://doi.org/10.1038/s43016-022-00657-x. The consistent use of cover crops – which are crops that are not planted for immediate harvesting but rather because they offer some ecosystem benefit – can help reduce emissions from fertilisers by adding more nitrogen to the soil and reducing nitrate leaching. This limits the need for nitrogen application, with some analyses finding that cover cropping reduces nitrate leaching by up to 69% compared to fields left to fallow.9Richard Waite and Alex Rudee, ‘6 Ways the US Can Curb Climate Change and Grow More Food’, World Resources Institute, August 20, 2020, https://www.wri.org/insights/6-ways-us-can-curb-climate-change-and-grow-more-food. 10Amin Nouri et al., ‘When Do Cover Crops Reduce Nitrate Leaching? A Global Meta‐analysis’, Global Change Biology 28, no. 15 (2022): 4736–49, https://doi.org/10.1111/gcb.16269.

Multiple studies confirm that agroecological practices can improve crop yields with fewer inputs compared to conventional farming practices.11Sieglinde S. Snapp et al., ‘Biodiversity Can Support a Greener Revolution in Africa’, Proceedings of the National Academy of Sciences 107, no. 48 (2010): 20840–45, https://doi.org/10.1073/pnas.1007199107; Gudeta Sileshi et al., ‘Meta-Analysis of Maize Yield Response to Woody and Herbaceous Legumes in Sub-Saharan Africa’, Plant and Soil 307, no. 1–2 (2008): 1–19, https://doi.org/10.1007/s11104-008-9547-y; Marc Corbeels et al., ‘Limits of Conservation Agriculture to Overcome Low Crop Yields in Sub-Saharan Africa’, Nature Food 1, no. 7 (2020): 447–54, https://doi.org/10.1038/s43016-020-0114-x; Shem Kuyah et al., ‘Agroforestry Delivers a Win-Win Solution for Ecosystem Services in Sub-Saharan Africa. A Meta-Analysis’, Agronomy for Sustainable Development 39, no. 5 (2019): 47, https://doi.org/10.1007/s13593-019-0589-8; Georges F. Félix et al., ‘Enhancing Agroecosystem Productivity with Woody Perennials in Semi-Arid West Africa. A Meta-Analysis’, Agronomy for Sustainable Development 38, no. 6 (2018): 57, https://doi.org/10.1007/s13593-018-0533-3. This is increasingly important as the effects of human-caused climate change, such as reduced rainfall, are anticipated to lower agricultural yields, thereby threatening food security. For example, a global systematic review of legume rotation – whereby staple crops are rotated with legumes – found a 20% increase in crop yields (rice, wheat and maize) on average compared to non-legume cropping systems.12Jie Zhao et al., ‘Global Systematic Review with Meta-Analysis Reveals Yield Advantage of Legume-Based Rotations and Its Drivers’, Nature Communications 13, no. 1 (2022): 4926, https://doi.org/10.1038/s41467-022-32464-0. In China, a long-term field experiment on the effects of intercropping – the simultaneous cultivation of two or more crops on one field – on grain yields found that yields were on average 22% higher than in comparable monoculture systems.13Xiao-Fei Li et al., ‘Long-Term Increased Grain Yield and Soil Fertility from Intercropping’, Nature Sustainability 4, no. 11 (2021): 943–50, https://doi.org/10.1038/s41893-021-00767-7. A review on the economic performance of agroecology in Europe found that agroecological farming generates incomes that exceed those of conventional agriculture, provides more employment per hectare, uses less fossil fuels and enhances biodiversity and landscapes.14Jan Douwe van der Ploeg et al., ‘The Economic Potential of Agroecology: Empirical Evidence from Europe’, Journal of Rural Studies 71 (2019): 46–61, https://doi.org/10.1016/j.jrurstud.2019.09.003.

A key finding of several of these studies is that the adoption of multiple agroecological practices maximises yield benefits over a single practice, and that these yield benefits tend to increase with time and are more stable year-to-year than in comparable conventional farming systems.

Improved ecosystem services, offering multiple benefits

Human-caused climate change is significantly impacting the provision of ecosystem services, defined as the benefits that humans derive from nature.15Yadvinder Malhi et al., ‘Climate Change and Ecosystems: Threats, Opportunities and Solutions’, Philosophical Transactions of the Royal Society B: Biological Sciences 375, no. 1794 (2020): 20190104, https://doi.org/10.1098/rstb.2019.0104. For example, changes in precipitation can lead to water scarcity, with knock-on effects for food production, or can lead to biodiversity loss, which would reduce the provision of various ecosystem services important for resilience. Studies show that farms with higher biodiversity show greater resilience to climate disasters.16Stacy M. Philpott et al., ‘A Multi-Scale Assessment of Hurricane Impacts on Agricultural Landscapes Based on Land Use and Topographic Features’, Agriculture, Ecosystems & Environment 128, no. 1–2 (2008): 12–20, https://doi.org/10.1016/j.agee.2008.04.016; Eric Holt-Giménez, ‘Measuring Farmers’ Agroecological Resistance after Hurricane Mitch in Nicaragua: A Case Study in Participatory, Sustainable Land Management Impact Monitoring’, Agriculture, Ecosystems & Environment 93, no. 1–3 (2002): 87–105, https://doi.org/10.1016/S0167-8809(02)00006-3. A number of studies from across the world have found that agroecological practices improve ecosystem services such as pollination, pest control, erosion, soil fertility and water management compared to conventional systems, and also enhance biodiversity.17Felipe Cozim-Melges et al., ‘Farming Practices to Enhance Biodiversity across Biomes: A Systematic Review’, npj Biodiversity 3, no. 1 (2024): 1, https://doi.org/10.1038/s44185-023-00034-2. 18Mario Torralba et al., ‘Do European Agroforestry Systems Enhance Biodiversity and Ecosystem Services? A Meta-Analysis’, Agriculture, Ecosystems & Environment 230 (2016): 150–61, https://doi.org/10.1016/j.agee.2016.06.002. 19Sara Palomo-Campesino, José A. González, and Marina García-Llorente, ‘Exploring the Connections between Agroecological Practices and Ecosystem Services: A Systematic Literature Review’, Sustainability 10, no. 12 (2018): 4339, https://doi.org/10.3390/su10124339. 20Matthew W. Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’, Forests 11, no. 12 (2020): 1321, https://doi.org/10.3390/f11121321. A third of the negative effects of landscape simplification – such as reduced provision of services and decreased crop production – were found to be due to decreased pollinator richness, emphasising the importance of practices that support pollinator diversity.21Matteo Dainese et al., ‘A Global Synthesis Reveals Biodiversity-Mediated Benefits for Crop Production’, SCIENCE ADVANCES, 2019, 4.

While conventional farming practices, such as intensive cultivation and pesticide use, are some of the biggest contributors to pollinator decline globally, agroecological practices increase the abundance and density of beneficial insects, reduce the abundance and density of insect pests, increase pollinator diversity, and reduce weed density and the abundance of parasitic and non-parasitic weeds.22Joseph Millard et al., ‘Global Effects of Land-Use Intensity on Local Pollinator Biodiversity’, Nature Communications 12, no. 1 (2021): 2902, https://doi.org/10.1038/s41467-021-23228-3. 23Charlie C. Nicholson et al., ‘Pesticide Use Negatively Affects Bumble Bees across European Landscapes’, Nature 628, no. 8007 (2024): 355–58, https://doi.org/10.1038/s41586-023-06773-3. 24Anjaharinony A.N.A. Rakotomalala, Anoush M. Ficiciyan, and Teja Tscharntke, ‘Intercropping Enhances Beneficial Arthropods and Controls Pests: A Systematic Review and Meta-Analysis’, Agriculture, Ecosystems & Environment 356 (2023): 108617, https://doi.org/10.1016/j.agee.2023.108617. 25Lorena Pumariño et al., ‘Effects of Agroforestry on Pest, Disease and Weed Control: A Meta-Analysis’, Basic and Applied Ecology 16, no. 7 (2015): 573–82, https://doi.org/10.1016/j.baae.2015.08.006. With pollination services globally valued at around USD 1 trillion, an abrupt pollinator collapse could cost around 1-2% of global GDP in the short term.26Christian Lippert, Arndt Feuerbacher, and Manuel Narjes, ‘Revisiting the Economic Valuation of Agricultural Losses Due to Large-Scale Changes in Pollinator Populations’, Ecological Economics 180 (2021): 106860, https://doi.org/10.1016/j.ecolecon.2020.106860.

Diversified farming systems, which are aligned with agroecology in that they incorporate different species or varieties rather than relying on single crops or species, in both high- and low-income countries are more profitable for farmers than conventional monoculture systems even when increased labour costs are considered, thereby dispelling myths that increased labour costs offset the benefits of diversification.27Andrea C. Sánchez et al., ‘Financial Profitability of Diversified Farming Systems: A Global Meta-Analysis’, Ecological Economics 201 (2022): 107595, https://doi.org/10.1016/j.ecolecon.2022.107595. In addition, diversification enhances biodiversity, pollination, pest control, nutrient cycling, soil fertility, and water regulation without compromising crop yields.28Giovanni Tamburini et al., ‘Agricultural Diversification Promotes Multiple Ecosystem Services without Compromising Yield’, Science Advances 6, no. 45 (2020): eaba1715, https://doi.org/10.1126/sciadv.aba1715. Estimates for rice suggest that diversification can increase biodiversity by 40%, improve economic performance, such as incomes and profits, by 26% and reduce crop damage by 31% in global production.29Xueqing He et al., ‘Agricultural Diversification Promotes Sustainable and Resilient Global Rice Production’, Nature Food 4, no. 9 (2023): 788–96, https://doi.org/10.1038/s43016-023-00836-4.

Diversification practices deliver multiple benefits relating to ecosystem services without compromising yield, highlighting that mainstream, high-yielding agricultural systems can benefit from diversification practices and that these practices can help bolster future sustainable food production.30Tamburini et al., ‘Agricultural Diversification Promotes Multiple Ecosystem Services without Compromising Yield’, 4.

Agroecological practices can also significantly decrease soil erosion – the most important indicator of land degradation – in temperate, tropical and mediterranean-type soils.31Mbezele Junior Yannick Ngaba et al., ‘Meta-Analysis Unveils Differential Effects of Agroforestry on Soil Properties in Different Zonobiomes’, Plant and Soil 496, no. 1–2 (2024): 589–607, https://doi.org/10.1007/s11104-023-06385-w. A systematic evidence map of temperate agroforestry on sheep and cattle productivity, environmental impacts and economics found that temperate agroforestry offers benefits compared to pasture without trees through sequestering carbon, reducing soil erosion, and improving water quantity and quality regulation.32Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’. There is also some evidence, albeit limited, that agroecological practices can improve livestock productivity.33Paulo César De Faccio Carvalho et al., ‘Land-Use Intensification Trends in the Rio De La Plata Region of South America: Toward Specialization or Recoupling Crop and Livestock Production’, Frontiers of Agricultural Science and Engineering 8, no. 1 (2021): 97, https://doi.org/10.15302/J-FASE-2020380. 34Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’.

Enhanced food security and health

As food systems are highly vulnerable to climate risks, improving resilience to these risks is important for ensuring food security. There is empirical evidence for agroecological practices such as livestock integration, intercropping, crop diversification, organic manure application and agroforestry in improving food security and resilience.35Gilbert Dagunga et al., ‘Agroecology and Resilience of Smallholder Food Security: A Systematic Review’, Frontiers in Sustainable Food Systems 7 (2023): 1267630, https://doi.org/10.3389/fsufs.2023.1267630. A 2024 review found that livestock diversification, soil conservation and non-crop diversification – practices not recognised as traditional crop production, such as the planting of hedgerows – improved food security in an assessment of 2,655 farms, and that a combination of these practices yielded greater improvements than they achieved singularly.36Laura Vang Rasmussen et al., ‘Joint Environmental and Social Benefits from Diversified Agriculture’, Science 384, no. 6691 (2024): 87–93, https://doi.org/10.1126/science.adj1914. A number of studies on the potential for agroecology to improve food security and nutrition have found that the number of agroecological practices implemented on a farm was positively associated with better food security and nutrition outcomes.

The demand for protein is projected to increase in the future, placing further demands on land and resources. Animal protein is an important source of nutrition, meaning a balance will need to be stuck between nutritional and environmental needs.37Maeve Henchion et al., ‘Future Protein Supply and Demand: Strategies and Factors Influencing a Sustainable Equilibrium’, Foods 6, no. 7 (2017): 53, https://doi.org/10.3390/foods6070053. A review on whether agroecology can help meet protein requirements for 2050 estimated that using an agroecological model where livestock are fed only on pasture, waste or by-products – and never fed on human-edible crops – can achieve a global diet within a limitation of 11–23 grams of protein per day from animal products.38Georgia Forsyth Sijpestijn, Alexander Wezel, and Sghaier Chriki, ‘Can Agroecology Help in Meeting Our 2050 Protein Requirements?’, Livestock Science 256 (2022): 104822, https://doi.org/10.1016/j.livsci.2022.104822.

The adoption of agroecological principles can help alleviate disease costs associated with pesticide exposure. Pesticides have been linked to ​​diabetes, reproductive disorders, neurological dysfunction, cancer and respiratory disorders in farmers.39Lata Rani et al., ‘An Extensive Review on the Consequences of Chemical Pesticides on Human Health and Environment’, Journal of Cleaner Production 283 (2021): 124657, https://doi.org/10.1016/j.jclepro.2020.124657. A meta-analysis found a link between mental illnesses such as depression and pesticide exposure in farmers, with affected farmers experiencing financial difficulties and poor health.40Mariane Magalhães Zanchi, Katiuska Marins, and Ariane Zamoner, ‘Could Pesticide Exposure Be Implicated in the High Incidence Rates of Depression, Anxiety and Suicide in Farmers? A Systematic Review’, Environmental Pollution 331 (2023): 121888, https://doi.org/10.1016/j.envpol.2023.121888. For the general public, the annual health and disease costs of exposure to organophosphate pesticides in 2010 were estimated at USD 121 billion in Europe and USD 42 billion in the US.41Teresa M Attina et al., ‘Exposure to Endocrine-Disrupting Chemicals in the USA: A Population-Based Disease Burden and Cost Analysis’, The Lancet Diabetes & Endocrinology 4, no. 12 (2016): 996–1003, https://doi.org/10.1016/S2213-8587(16)30275-3. Exposure to pesticides in Europe in 2003 was estimated to cause an average burden of lifetime lost per person of 2.6 hours and up to 45.3 days, and average costs per person over lifetime of EUR 12 and up to EUR 5,142.42Peter Fantke, Rainer Friedrich, and Olivier Jolliet, ‘Health Impact and Damage Cost Assessment of Pesticides in Europe’, Environment International 49 (2012): 9–17, https://doi.org/10.1016/j.envint.2012.08.001. In addition, as pollinators are directly responsible for up to 40% of the world’s micronutrient supply, including essential micronutrients such as vitamin A, pollinator collapse could result in 1.42 million additional deaths per year from non-communicable and malnutrition-related diseases, and 27 million lost disability-adjusted life-years annually at the global scale.43Matthew R Smith et al., ‘Effects of Decreases of Animal Pollinators on Human Nutrition and Global Health: A Modelling Analysis’, The Lancet 386, no. 10007 (2015): 1964–72, https://doi.org/10.1016/S0140-6736(15)61085-6.

Sequestration in plants and soil can help meet Nationally Determined Contributions

Estimates suggest that agroforestry can sequester 0.12 to 0.31 gigatons of carbon (Gt C) per year, making it comparable to other nature-based solutions such as reforestation (0.27 Gt C per year) and reduced deforestation (0.49 Gt C per year).44Drew E. Terasaki Hart et al., ‘Priority Science Can Accelerate Agroforestry as a Natural Climate Solution’, Nature Climate Change 13, no. 11 (2023): 1179, https://doi.org/10.1038/s41558-023-01810-5. Agroforestry has also been identified as a key intervention for achieving Nationally Determined Contributions (NDCs). A 2023 review looked at the extent to which agroforestry is represented in current NDCs in 22 developing countries and found that more than 80% of countries that experienced deforestation between 2000 and 2015 could meet their unconditional NDC targets by converting 25% of deforested lands to agroforestry.45Jagdish Chander Dagar, Sharda Rani Gupta, and Gudeta Weldesemayat Sileshi, eds., Agroforestry for Sustainable Intensification of Agriculture in Asia and Africa, Sustainability Sciences in Asia and Africa (Singapore: Springer Nature Singapore, 2023), https://doi.org/10.1007/978-981-19-4602-8. Integrating agroecological practices into countries’

National Biodiversity Strategies and Action Plans (NBSAPs) can also help fulfill Global Biodiversity Framework (GBF) commitments by encouraging the use of sustainable practices that protect biodiversity, build climate resilience and enhance food security.46‘FAOLEX Database’, Food and Agriculture Organization of the United Nations, 2023.

A literature review on soil carbon sequestration in the context of climate change found that agroecological practices such as the incorporation of organic matter into the soil, crop rotation and the use of cover crops can improve soil carbon sequestration.47Cristina I. Dias Rodrigues, Luís Miguel Brito, and Leonel J. R. Nunes, ‘Soil Carbon Sequestration in the Context of Climate Change Mitigation: A Review’, Soil Systems 7, no. 3 (2023): 64, https://doi.org/10.3390/soilsystems7030064. One analysis suggests that increasing the soil organic carbon pool of degraded croplands using agroecological practices has the potential to increase yields of wheat by 20-40 kg per hectare, maize yields by 10-20 kg per hectare and cowpea yields by 0.5-1 kg per hectare.48R. Lal, ‘Soil Carbon Sequestration Impacts on Global Climate Change and Food Security’, Science 304, no. 5677 (2004): 1623–27, https://doi.org/10.1126/science.1097396. The analysis also suggests that this approach can offset fossil fuel emissions by 0.4-1.2 Gt C per year, which is as much as 3% of current global fossil fuel emissions. Other estimates suggest that improved cropland management using agroecological principles could mitigate around 1.4–2.3 Gt carbon dioxide equivalent per year (CO2eq/year), while improved grazing management could mitigate 1.4–1.8 Gt CO2eq/year.49Pete Smith et al., ‘Which Practices Co‐deliver Food Security, Climate Change Mitigation and Adaptation, and Combat Land Degradation and Desertification?’, Global Change Biology 26, no. 3 (2020): 1532–75, https://doi.org/10.1111/gcb.14878.

The potential for sequestration will be highly context-specific, and the possible reversal of sequestration benefits remains an important limiting factor, especially for soil carbon.50Cécile M. Godde et al., ‘Soil Carbon Sequestration in Grazing Systems: Managing Expectations’, Climatic Change 161, no. 3 (2020): 385–91, https://doi.org/10.1007/s10584-020-02673-x. Carbon sequestered in the soil can be retained for as long as agroecological practices are maintained and with minimal disturbance to the soil, thereby helping to address issues around the permanence of the sequestered carbon.51Lal, ‘Soil Carbon Sequestration Impacts on Global Climate Change and Food Security’. The consistent application of sustainable management practices is important for realising the mitigation benefits of soil and plant carbon sequestration.52Rodrigues, Brito, and Nunes, ‘Soil Carbon Sequestration in the Context of Climate Change Mitigation’.

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Relying on soil-based carbon capture to offset livestock emissions is risky

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Key points:

  • Soil carbon sequestration is the process through which atmospheric carbon dioxide is captured and stored in soil, forming part of the natural global carbon cycle.
  • In undisturbed natural ecosystems, carbon may be stored in the soil for thousands of years. However, the conversion of natural land into farmland has depleted soil organic carbon stocks and released this stored carbon into the atmosphere.
  • Livestock grazing systems are responsible for the loss of significant amounts of soil carbon over the past six decades.
  • Regenerative grazing – which involves rotating livestock on land for short durations – has been proposed as a solution for improving soil carbon stocks and offsetting emissions from livestock farming.
  • Recent estimates suggest that improved grazing management could potentially take-up around 63  gigatons (billion metric tons) of carbon in vegetation and soils.
  • However, once methane and nitrous oxide emissions from grazing animals are considered, an estimated 135 gigatons of carbon take-up would be needed to offset these emissions.
  • Relying on soil carbon sequestration to offset emissions from grazing systems is risky as carbon storage is finite and reversible, and increased emissions of methane and nitrous oxide could offset any gains from carbon sequestered in the soil. The impacts of regenerative grazing are also highly context-dependent.
  • Despite uncertainties, sequestering carbon in soil could contribute to climate change mitigation in the medium term in certain regions of the world.
  • Management practices aimed at maintaining or improving soil carbon offer other benefits, such as improved soil health, erosion control and reduced emissions intensity, with positive outcomes for yields and farmers’ incomes.


Soil carbon sequestration: the basics

Soil carbon sequestration is the process through which atmospheric carbon dioxide is captured and stored in soil. Plants capture atmospheric carbon dioxide through photosynthesis, and the carbon is stored in its organic form in plant tissues while the oxygen is released back into the atmosphere. As the leaves, roots and other tissues of plants decay, the carbon contained in these tissues is released into the soil through microbial activity, enriching the soil carbon pool. The carbon pool is also enriched through the exchange of carbon between plant roots and soil microbes.

Soil carbon sequestration is a natural process that forms a critical part of the global carbon cycle – whereby carbon is exchanged among all life on earth, the soil, water, minerals and the atmosphere. Soil organic carbon is important because it regulates the functioning of ecosystems, provides energy for soil microorganisms and improves the structure of soil. It is also an important carbon sink – the soil organic carbon pool contains up to 2,400 gigatons (or billion metric tons) of carbon, which is more than double that of the atmospheric carbon pool.

In undisturbed natural ecosystems, carbon may be stored in the soil for thousands of years. However, the conversion of natural land into agricultural land from human activities has depleted soil organic carbon stocks by reducing the amount of plant tissues in soil and encouraging erosion, thereby destroying soil structure and speeding up microbial breakdown. It is estimated that over the last 15,000 years, and particularly in the last 200 years, the growth of farmland has released 133 gigatons of carbon from the top two metres of the soil layer. This is equivalent to about 80 years’ worth of present-day US emissions.

This deficit of soil organic carbon has created an opportunity to draw earth-warming carbon dioxide from the atmosphere and store it in the soil in an effort to mitigate against climate change.

Grazing systems and soil organic carbon

Grasslands are a significant reservoir of soil carbon, storing around one-third of the global soil organic carbon pool.1This definition of grasslands includes some savannas, woodlands, shrublands and tundra. However, estimates suggest that livestock grazing is responsible for the loss of 46 gigatons of soil carbon over the past six decades – which is more than four years’ worth of current global fossil fuel emissions.

While moderate to heavy livestock grazing depletes the soil organic carbon pool on average, light grazing has been found to increase soil organic carbon stocks. This is because grazing can stimulate plant productivity and the allocation of carbon to the roots for microbes, thereby increasing carbon sequestration.2Some studies show that grazing-induced changes in vegetation are not correlated with changes in soil organic carbon. As a consequence, ‘regenerative grazing’ – which involves rotating livestock on land for short durations to allow soil to recover and draw carbon dioxide from the atmosphere – has been proposed as a solution for improving soil carbon stocks and mitigating the climate change impacts of livestock grazing. Currently, global grazing systems emit more greenhouse gases than they sequester.

A 2021 analysis found that ‘adaptive multi-paddock grazing’ – a form of regenerative grazing – increased soil carbon stocks compared to conventional grazing. The authors emphasised the importance of carbon being stored in the mineral fraction of the soil – meaning it is tightly bound to soil particles. This makes the sequestered carbon more resistant to disturbance and means it will be stored for a longer duration. The study is backed by a global meta-analysis, which found that regenerative practices, particularly integrated crop-livestock systems, have significant potential to increase soil organic carbon pools because they enhance the storage of carbon in the mineral soil fraction.

Another study reported that over a four-year period, the emissions from adaptive multi-paddock grazing on a beef farm could be completely offset by the carbon sequestered in the soil. Some advocates of regenerative grazing have gone as far as claiming it can ‘reverse climate change’. They argue that increasing livestock production could help sequester more carbon from the atmosphere into the soil.3This is in contrast to experts who believe that managing livestock numbers will be essential, together with other strategies, for reaching Paris Agreement commitments.

A long-term field experiment found that rotational grazing accumulated more soil organic carbon than other management systems. However, the findings have been questioned by other scientists, who point out that the analysis did not consider the contribution of methane and nitrous oxide – two significant greenhouse gases associated with livestock farming – and the method for measuring the permanence of soil carbon was unsuitable. According to these scientists, “grazing cattle, well-managed or not, has no role in enhanced C sequestration.”

How much carbon could these strategies sequester?

An analysis published this year estimates that improved grazing management could take-up around 63 gigatons of carbon in vegetation and soils globally. This number is three times higher than IPCC estimates, which the authors attribute to the overly simplistic model used by the IPCC. To put the number into perspective, 63 gigatons is about six years’ worth of emissions from fossil fuels globally.

A separate analysis published in 2022 suggests that 148 to 699 megatons (or million metric tons) of carbon dioxide equivalent could be sequestered in the soil globally every year through improved grazing management.4Other estimates suggest that improved grazing management could sequester 0.28 megatons of carbon per hectare per year.

Sequestration potential overstated

Some scientists are more cautious and suggest that the potential for soil carbon sequestration under regenerative agriculture to offset emissions may be greatly overestimated. There are several reasons why relying on soil carbon sequestration to offset emissions from livestock systems is risky.

1. The capacity for soil to store carbon is finite

In long-term undisturbed ecosystems, soil carbon stocks are assumed to be equal to soil carbon emissions because the system has reached a state of equilibrium, or a steady state. When the ecosystem is disturbed – such as a grassland being overstocked with cattle – carbon is released from the soil due to, for example, erosion from reduced vegetation cover. Once a new land management practice aimed at enhancing soil carbon sequestration – such as rotational grazing – is introduced on this disturbed land, the rate of soil carbon sequestration follows a sigmoid curve, being high during the initial period after adoption of the practice and then slowing down upon approaching a new soil carbon steady state (Figure 1).

Figure 1. Soil carbon sequestration after a new management practice is introduced
Note: Figure has been adapted from Considering the influence of sequestration duration and carbon saturation on estimates of soil carbon capacity, 2006. The graph is theoretical and the axes are not true to scale.

The new steady state reflects a balance between carbon inputs and outputs under the new management practice, with soil carbon stocks no longer increasing. For grassland management, estimates suggest that the time until the maximum sequestration is reached is, on average, around five years, with declining rates for another 45 years. In other words, the rate of carbon sequestered within the first several years of a new practice being introduced does not reflect the long-term total sequestration rate.

Initial soil carbon sequestration rates from short-term studies on regenerative grazing should therefore not be extrapolated to estimate the total soil carbon sequestration potential of the practice. In some cases, the carbon sequestration potential can be improved beyond the new steady state with the addition of inputs, such as manure.5Importantly, inputs such as manure can also increase the emissions of other greenhouse gases, offsetting soil carbon sequestration gains. Soil carbon saturation then occurs when further inputs no longer lead to increased carbon stores, representing a cap on the carbon storage capacity.6Estimates suggest that saturation is reached at 82 g C kg-1 silt+clay for 2:1 clay dominated soils and 46 g C kg-1 silt+clay for 1:1 clay dominated soils.

2. Soil carbon storage is reversible

For the sequestered carbon to remain in the soil, and for the rate of sequestration to reach its full potential, the new practice needs to be implemented permanently. However, disturbances such as fires or floods – which can be difficult to predict and control – could reverse the practice and cause the release of stored carbon. Climate change is contributing to this reversibility, causing the release of decades-old soil organic carbon by thawing permafrost and accelerating microbial decomposition. This creates a positive feedback loop that further accelerates global warming. As soil organic carbon is sensitive to temperature changes, it is estimated that the potential storage capacity could decrease by 14% by 2040 under a moderate global warming pathway.7The SSP3−7.0 pathway from CMIP6.

3. Warming potential of other greenhouse gases

Land management changes that enhance soil carbon sequestration may increase the emissions of other, more potent, greenhouse gases. In certain cases, even small increases in these other gases may offset the benefit from the change in soil carbon stocks offered by the practice. Ruminant (cows, buffaloes, sheep and goats) farming emits nitrous oxide (from manure), which has a global warming potential 265 times that of carbon dioxide, and methane (from belching animals), which has a warming potential 28 times that of carbon dioxide. They are both also shorter-lived gases than carbon dioxide and have a stronger initial warming effect. Estimates suggest that ruminants emit 110 megatons of methane and 2.4 megatons of nitrous oxide every year, in addition to carbon dioxide.8The ratio of emitted methane: carbon dioxide in ruminants is 4:1. Studies claiming regenerative grazing systems have a net benefit have been criticised for failing to consider the warming contributions of these gases.

A 2023 study estimated the potential for ruminant emissions to be offset through soil carbon sequestration in grasslands, considering the different warming potentials and lifespans of these greenhouse gases. The analysis suggests that around 135 gigatonnes of carbon would need to be sequestered in order to offset global methane and nitrous oxide emissions from ruminant farming – more than double the carbon sequestration potential of improved grazing management. For some grasslands, the soil carbon stock would need to increase by up to 2,000%, which emphasises how infeasible grassland management might be for offsetting ruminant emissions once the warming from other gases is considered.

4. Context is important

Though moderate to heavy grazing consistently reduces soil carbon stocks on average on a global scale, the impacts are highly context-dependent and will vary depending on a number of factors such as the climate conditions, type of soil, type of grazer, the vegetation type and the grazing strategy used. For example, sheep have a greater negative impact on soil carbon sequestration than cattle; the impacts of a higher grazing intensity will be more severe in warmer climates but less severe when water availability is high; and certain types of grasses will improve carbon sequestration, even under heavy grazing.

Due to this wide variability, some scientists argue that it is difficult to anticipate the soil sequestration potential of regenerative grazing practices. There are also concerns that farmers’ skills and motivation levels could limit the outcomes and scalability of practices. Difficulties in measuring the results also makes monitoring soil carbon stocks challenging – it typically takes a decade of monitoring to determine how much carbon a practice is sequestering.

Soil carbon markets

Through soil carbon markets or ‘carbon farming’, farmers implement a management practice that allows them to sell ‘carbon credits’. The credits, a quantifiable amount of carbon dioxide that has been sequestered in the soil from the management practice, are being proposed as a solution to mitigate climate change, with millions of dollars’ worth of credits already sold. However, the uncertainties around the permanence, monitoring and accounting of soil carbon make soil carbon certificates unsuitable for climate change mitigation.9While permanence is a necessary condition for creditable carbon offsets – which are typically issued over a 100-year period – this permanence refers to the duration for which the sequestration practice is carried out rather than the stored soil carbon. Therefore, when the practice ends and the carbon is lost to the atmosphere, it is no longer a permanent removal. As emphasised by a prominent soil scientist, “It’s really hard to evaluate the actual greenhouse gas benefit of these programs”.

Sequestration offers important benefits

Despite several limitations, sequestering carbon in soil could make a meaningful contribution to climate change mitigation in the medium term in certain regions of the world, depending on the management strategy that is used. For example, converting arable land to grassland or forest will almost always have a positive effect on soil carbon sequestration. In addition, many management strategies are well-established and are not reliant on the development of new technologies, meaning they can be implemented quickly and with relative ease.

Additionally, management practices aimed at maintaining or improving soil carbon typically offer multiple other benefits, such as improved soil health, erosion control, increased water availability and reduced emissions intensity, with positive outcomes for yields and farmers’ incomes.

Smallholder farmers, agricultural sustainability and global food security

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Key points:

  • Smallholder farms of two to five hectares produce 46% of the world’s food on around one-third of the world’s agricultural land. They are major producers of key global agricultural products, such as rice, peanut, coffee, cocoa, bananas and tea.
  • Smallholder farms tend to have higher food yields per hectare than larger farms, attributed to dedicating a larger share of their land to food crops (rather than animal feed or fuel), employing family members (which lowers transaction costs and increases labour intensity per unit of land) and high fertiliser and seed use.
  • Smallholder farms tend to have higher crop and non-crop biodiversity than larger farms. This is due to their use of varied crops and ecological land management practices, including limited insecticide use, more field edges providing a habitat and breeding ground for insects, and diverse land cover types, such as forests, fields and wetlands.
  • Sustainable and climate-smart agricultural practices are already implemented in many smallholder farming systems. In Africa, organic manure, agroforestry, crop rotation and crop diversification are common practices.
  • The availability of finance has been identified as one of the most significant variables influencing whether or not smallholder farmers in Africa adopt climate-smart agricultural practices.
  • Ensuring that smallholder farmers can access modern agrifood chains is critical for ensuring food security, productivity and nutrition.
  • Growth and investment in smallholder agriculture has significant potential to alleviate poverty for smallholder farmers while supporting global food security.

Smallholder farmers are important for rural and national economies, development and food security

Smallholder farming is the most common type of agriculture in the world.1Smallholder farmers are small-scale farmers, pastoralists, forest keepers and fishers who manage smaller tracts of land, using mainly family labour and dedicating at least some of the produce to household consumption. Farms of less than two hectares in size produce around one-third of the world’s food, while those two to five hectares in size produce almost half. Farms of less than five hectares located in developing countries account for more than half of the global production of nine staple crops – rice, peanut, cassava, millet, wheat, potato, maize, barley and rye – demonstrating their importance for global food security. As shown in Figure 1, farms of less than two hectares produce the majority of rice (>80%), peanut (75%), cassava and millet (~60%) globally. Smallholder farmers are also major producers of food that is consumed in their country. For example, smallholders in Tanzania meet around 69% of national food demand, and 2.7 million smallholder farmers in Nepal produce around 70% of their country’s food.

Fig. 1: Share of global production of major food crops in developing countries according to farm size
Source: Subnational distribution of average farm size and smallholder contributions to global food production.2This study used data on smallholder farms from 83 countries in Latin America, Sub-Saharan Africa, and South and East Asia, which is where 90% of the world’s farms are located. Farms over 50 hectares are largely grazed lands.

The role different size smallholdings play in producing food calories varies by region (Figure 2). In Asia, farms of less than five hectares produce 90% of food calories, whereas in Sub-Saharan Africa, farms of this size produce around half of food calories and farms of 5-15 hectares produce another 26%. By contrast, 70% of food calories in Latin America are produced on larger farms (> 15 hectares), while only 7% are produced on farms of less than five hectares.3This estimate is based on 41 major food crops.

Fig. 2: Calories produced by farms of different sizes in Asia, Latin America and Sub-Saharan Africa
Source: Subnational distribution of average farm size and smallholder contributions to global food production.4This study used data on smallholder farms from 83 countries in Latin America, Sub-Saharan Africa, and South and East Asia, which is where 90% of the world’s farms are located.
Despite their size, smallholder farms are highly productive

Farms of smaller than two hectares produce around one-third of the world’s food on just one-quarter of the world’s agricultural land and those two to five hectares in size produce 46% of food on one-third of agricultural land. Small-scale farms have been found to have higher land productivity – the farm’s output per unit of land area – than larger farms. For example, in Kenya, a farmer farming on less than half a hectare of land produces USD 888 of food per hectare on average, whereas a farmer farming on two hectares of land produces food to the value of USD 330 per hectare.

On average, smallholder farms dedicate a larger share of their land to food crops – rather than animal feed or fuel – compared to larger farms. Around 70% of the calories produced on smallholder farms of less than five hectares are available as food, compared to 55% for the global agricultural system.2

Another reason smallholder farms are able to achieve high productivity is their high labour intensity. Employing family members allows for a higher number of labourers per hectare and keeps labour transaction costs low.

As smallholder farmers need to optimise production on small tracts of land, they also tend to use more inputs, such as fertiliser and seeds, than larger farms.5This comparison is between small and large farms within the same country. For example, smallholder rice farmers in Bangladesh apply 181 kg of fertiliser on average per hectare, whereas larger farms only apply around 130 kg.

Though smaller farms are more productive than their larger counterparts in many developing countries, yields could be improved with the adoption of modern technologies and optimised inputs, such as fertiliser, manure and seeds. This ‘yield gap’ – the amount by which yields could be improved – ranges from 11% in East Asia to up to 76% in Sub-Saharan Africa, emphasising the significant potential for farmers in developing countries to contribute even further to rural and national food security.
Reaching this potential is contingent on smallholder farmers having access to and participating in modern food supply chains. For example, smallholder farmers may not have access to roads or transport to get their produce to market, they may lack access to suitable storage facilities to reduce food spoilage, or they may not have access to the technology needed to communicate with buyers or to learn about food safety and quality control requirements.

Smallholder farmers and global food supply chains

Ensuring that smallholder farmers can access modern agrifood supply chains is critical for ensuring food security, productivity and nutrition. Smallholder farmers produce some of the world’s most important agricultural products. For example:

Smallholder farms have a potential competitive advantage over larger farms when producing labour-intensive and high-value products, though they face difficulties linking these products to modern value chains. Growth and investment in smallholder agriculture has significant potential to alleviate poverty for smallholder farmers while concurrently supporting global food security.

For example, obtaining an Ecocert Organic Standard certification allowed pineapple growers in Zimbabwe to sell their organic produce internationally. Accessing these supply chains will enhance the farmers’ livelihoods – their pineapples could fetch as much as a 30% premium in European supermarkets. Obtaining this certification was made possible with assistance from organisations including the Committee linking Entrepreneurship – Agriculture – Development (COLEAD), the Embassy of Netherlands in Zimbabwe, the Netherlands-based Programma Uitzending Managers (PUM) and the Netherlands Enterprise Agency (RVO), highlighting the importance of collaboration in facilitating access of smallholder farmers to international food supply chains.

Similarly, smallholder avocado farmers in Tanzania were able to access the European export market through help from the private sector companies Africado and Rungwe Avocado Company, both supported by US food security initiative Feed the Future. Another example is macadamia nuts in Malawi, where a Dutch-Malawian partnership has facilitated the export of sustainably-produced macadamias to the European market.

Smallholder farming is important for GDP

Agriculture contributes substantially to the GDP of many developing nations, with smallholder farming playing a significant role. For instance, in Sub-Saharan Africa, where the majority (up to 80%) of farming is done by smallholder farmers, agriculture contributes 23% to GDP. Agriculture GDP values are even higher for certain African countries – for example, 41% of the GDP of Liberia and 31% of the GDP of Guinea-Bissau is attributed to agriculture.

In Sub-Saharan Africa, more than 60% of the population are smallholder farmers and smallholder farms employ up to 65% of the labour force. Around 73% of the population of Tanzania lives in rural areas, where 3.7 million smallholdings support up to 19 million people. In Malawi, smallholder farmers produce 80% of the country’s food and more than 80% of the working population are employed in agriculture.

Smallholder farmers practise climate resilient and sustainable agriculture

Sustainable and climate-smart agricultural practices are already an integral part of many indigenous farming systems. For example, traditional fallow systems, crop rotation and water harvesting practices in the Sahel aim to improve crop yields and livelihoods, and conserve water. In Nigeria, indigenous knowledge and practices are implemented by farmers to improve agricultural productivity and food availability, including mulching, using organic manure, using locally made pesticide, no-tillage and treating seeds with ash for long-term preservation. In South Africa, subsistence farmers use indigenous knowledge and practices such as planting in different soil types, fertilising soil with manure, selecting seeds by colour and size, and storing seeds in ash in clay pots and baskets to preserve them.

Fig. 3: Climate-smart agricultural practices used by smallholder farmers in Sub-Saharan Africa
Source: Contribution of smallholder farmers to food security and opportunities for resilient farming systems. See our explainer on sustainable agriculture in small-scale farming.

Figure 3 shows 17 different climate-smart farming practices that are used by farmers in Sub-Saharan Africa.6Fourteen Sub-Saharan African countries were included in the analysis: South Africa, Zimbabwe, Malawi, Zambia, Tanzania, Kenya, Uganda, Ethiopia, Cameroon, Nigeria, Niger, Burkina Faso, Ghana and Senegal. The most widely-adopted practice is using organic manure, followed by agroforestry (where annual crops or pastures are farmed together with trees or shrubs), crop rotation and crop diversification. In Ghana, smallholder farmers use a range of climate-smart agricultural practices, including timely harvesting and storing of produce, crop rotation, appropriate and timely weed and pest control, appropriate fertiliser use, mixed cropping (where two or more crops are grown simultaneously), planting legumes among crops, conservation agriculture (agriculture focused on regenerating degraded lands and preserving arable land) and agroforestry, among others. The primary motivations for adopting these practices are improving household food security, reducing pests and diseases, increasing yields and farm income, and controlling erosion and protecting soil. In Nicaragua, smallholder coffee producers implement agroforestry to reduce production costs, improve livelihoods and diversify income.

Table 1: Comparison of the yield, crop and non-crop biodiversity and efficiency of small farms and large farms
Source: Higher yields and more biodiversity on smaller farms

Smallholder farmers tend to plant a greater diversity of crops than larger farms in order to improve nutrition, mitigate drought risk and for market diversification (Table 1). Smallholder farms also have higher non-crop biodiversity than larger farms, which has been attributed to the use of ecological management practices, such as limited insecticide use, the presence of field edges – which provide a habitat and breeding ground for insects – and diverse land-cover types, such as forests, fields and wetlands. Smallholder farms within and around cities can also improve the environment by reducing urban heat island effects and can improve access to easy and affordable nutritious foods for city dwellers.

Encouraging climate-smart agriculture for smallholders farmers

The availability of finance has been identified as one of the most significant factors influencing whether smallholder farmers in Africa adopt climate-smart agricultural practices. In Malawi, access to credit was found to be a major factor dictating the adoption of climate-smart agriculture. In Ghana, maize farmers farming smaller lands face more credit constraints than those farming larger lands. Both private and public financing approaches are needed to encourage the adoption of sustainable agricultural practices by smallholder farmers, who are often lacking the necessary financial resources.

In Kenya, farmers that are more likely to adopt climate-resilient farming practices are those that sell their produce to markets (as opposed to farming entirely for subsistence) and have off-farm activities related to agricultural supply chains, such as milling their grains to add value to their produce or hiring out their farm equipment. Having individual land tenure rights and having middle to high school education were also found to be factors.

  • 1
    Smallholder farmers are small-scale farmers, pastoralists, forest keepers and fishers who manage smaller tracts of land, using mainly family labour and dedicating at least some of the produce to household consumption.
  • 2
    This study used data on smallholder farms from 83 countries in Latin America, Sub-Saharan Africa, and South and East Asia, which is where 90% of the world’s farms are located.
  • 3
    This estimate is based on 41 major food crops.
  • 4
    This study used data on smallholder farms from 83 countries in Latin America, Sub-Saharan Africa, and South and East Asia, which is where 90% of the world’s farms are located.
  • 5
    This comparison is between small and large farms within the same country.
  • 6
    Fourteen Sub-Saharan African countries were included in the analysis: South Africa, Zimbabwe, Malawi, Zambia, Tanzania, Kenya, Uganda, Ethiopia, Cameroon, Nigeria, Niger, Burkina Faso, Ghana and Senegal.

An introduction to sustainable agriculture in smallholder farming

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Key points:

  • Smallholder farmers produce at least one-third of the world’s food 
  • Smallholder farmers are disproportionately experiencing the effects of climate change and are particularly vulnerable to climate shocks, yet it is estimated that they receive only 1.7% of total climate finance
  • The FAO describes sustainable agriculture as meeting “the needs of present and future generations, while ensuring profitability, environmental health, and social and economic equity”
  • Various farming approaches can be considered sustainable, such as sustainable intensification, climate-smart agriculture, regenerative agriculture, organic farming and agroecological farming
  • The WEF recognises that farmers are key to addressing the current ecological and climate crises and need to be supported through the provision of financing and fair economic opportunities in order to embrace sustainable food production practices
  • Ninety-five percent of climate finance for small-scale agriculture comes from the public sector, including government donors, multilateral development finance institutions and bilateral development financial institutions
  • Smallholder farmers are vulnerable to production risks, so they need initiatives and investments that are relatively low-risk and that offer short-term returns on investment
  • Impact-oriented funds, blended finance and green bonds offer finance solutions for climate resilient and sustainable agriculture. 

Smallholder farming

More than half of agricultural land globally is degraded, leading to productivity losses of USD 400 billion every year. Projections indicate that globally, agricultural production will need to expand by 60% by 2050 to meet increased demand, and most of this will need to come from increased productivity. Food production also makes up more than a third of greenhouse gas emissions worldwide, of which 58% is from animal-based agriculture (including livestock feed) and 29% is from the production of plant-based foods. 

Smallholder farms of less than two hectares in size produce around one-third of the world’s food. Farms of up to 20 hectares produce over half (see the chart below).1Small-scale farmers are typically those that produce food on up to two hectares of land in Asia and Africa and up to 15 hectares in Latin America. Small-scale farmers may or may not hold land titles. These farms face various production risks due to a range of factors, including they are small in size, are held under traditional or informal land tenure, are more vulnerable to market shocks, are constrained by low soil productivity and low-quality or marginal lands, feature complex production systems hosting a diversity of plants and animals, face regulatory regimes in the Global North that have strict and ever-changing policies on food security and safety, suffer from isolation and low levels of technology, and may be subject to armed conflict and state fragility.

Source: Our World in Data

Small-scale farmers, particularly in developing countries, therefore play a crucial role in ensuring food security despite experiencing major food insecurity themselves. Smallholder farmers are disproportionately vulnerable to the effects of climate change and climate shocks, yet it is estimated that they receive only 1.7% of total climate finance. The World Economic Forum (WEF) recognises that farmers are key to addressing the current ecological and climate crises and need to be supported through the provision of financing and fair economic opportunities in order to embrace sustainable food production practices.

Sustainable agriculture

The Food and Agriculture Organization (FAO) describes sustainable agriculture as meeting “the needs of present and future generations, while ensuring profitability, environmental health and social and economic equity”. Various types of agricultural production can be considered sustainable, and these are discussed below.  

Sustainable intensification

The main aim of sustainable intensification is to increase crop and livestock yields and the associated economic activity without negatively impacting soil, water or the integrity of natural ecosystems. In general, this means a move away from the typical seed, fertiliser and pesticide technologies used in modern agriculture to restorative practices that rely more on ecological processes and internal resources. It also means increasing output on existing agricultural land and reducing the loss of natural habitat for agricultural production. Examples of how agricultural systems in both developed and developing countries may be redesigned to fit the principles of sustainable intensification are provided in the table below:

Source: Global Assessment of Agricultural System Redesign for Sustainable Intensification

Many argue that sustainable intensification can only be achieved if public investments encourage the adoption of innovations and support farmers by making technologies accessible and affordable. As smallholder farmers are vulnerable to production risks, they need initiatives and investments that are relatively low-risk and that offer short-term returns. 

For example, agroforestry, which is one of the tools that can be used in different types of sustainable agriculture and involves planting trees alongside pasture and crops, is being supported by the non-profit research institute CIFOR-ICRAF. Their Trees for Food Security II project trained smallholder farmers in Africa in agroforestry principles and business skills, allowing them to participate more effectively in timber, fruit and fodder value chains while increasing outputs and improving sustainability. Another initiative is designed to demonstrate to smallholder oil palm producers in Cameroon that the use of industrial mills is more efficient than small local mills and could improve their productivity and income. Research supported by research centre CIFOR-ICRAF has shown that pests in Zambia and Malawi that would ordinarily be controlled using pesticides can be managed through the use of low-cost agroecological farming principles.2Conventional pesticides are expensive for these farmers, who often do not have access to adequate protective clothing.

Sustainable intensification and climate-smart agriculture (discussed below) are closely interlinked, with sustainable intensification forming the foundation of climate-smart agriculture. Therefore, the constraints, solutions and financing options discussed below under climate-smart agriculture will be broadly applicable to sustainable intensification.

Climate-smart agriculture

Climate-smart agriculture aims to guide agricultural systems towards supporting food security in the context of a changing climate, through “integrating climate change into the planning and implementation of sustainable agricultural strategies”. As climate change presents considerable risk in terms of unpredictable weather patterns, climate-smart agriculture focuses on building resilience in order to respond more rapidly to these risks and reduce the chances of becoming food insecure. It has three broad principles:

  • Increased sustainable production to meet food security and equitably increase incomes, food security and development 
  • Enhanced resilience to climate shocks and risks through adaptation and resilience building
  • Development of opportunities to reduce greenhouse gas emissions from agriculture, thereby reducing the greenhouse gases emitted per calorie of food. 

Climate-smart agriculture uses existing approaches focused on supporting ecosystem services for achieving these principles, with sustainable intensification being a foundation.3Ecosystem services are the basic services that are provided by the natural environment that offer benefits to humans, such as pollination The tools and approaches that are used will vary depending on the regional context, but some examples include:

  • Integration of crop, livestock, agroforestry and aquaculture systems 
  • Improved management of pests, water and nutrients, including using nitrogen fertiliser more efficiently  
  • Landscape approaches, which focus on the use of collaborative initiatives in farming
  • Improved management of forests and grasslands, and the integration of trees into agricultural systems  
  • Reduced tillage and the use of a variety of breeds and varieties
  • Restoration of degraded land
  • Manure management, which may include the use of anaerobic bio-digesters.

A recent analysis of climate-smart agriculture on small-scale farms found the common barriers to be poor education, skills and knowledge; potentially high investment costs and delayed benefits; and uncertainty.

The constraints and potential solutions have been summarised in the table below:

Source: Climate-Smart Agriculture on Small-Scale Farms: A Systematic Literature Review

This analysis highlights that knowledge sharing and education, among other factors, are key to realising climate-smart agriculture. Solutions also need to consider that the benefits and costs of agricultural transitions differ in different social groups and contexts. 

An analysis by McKinsey identified the approaches that could be taken by government, development partners and the private sector to encourage the adoption of climate-smart agricultural measures for smallholder farmers. Among other things, it recommended the following:

  • Provision of opportunities for land-use optimisation linked to financing and incentive mechanisms 
  • Redesign of subsidies and tax incentives for the adoption of adaptation and mitigation measures 
  • Design of agricultural lending products that are are linked to the adoption of adaptation and mitigation measures 
  • Investment in infrastructure to reduce postharvest losses and investment to make infrastructure more resilient (such as flood protection) 
  • Improvement of traceability and sustainability certifications for applicable crops 
  • Launch of a results-based payment scheme tied to specific goals 
  • Scaling of investment in research and development of technologies for mitigation and adaptation, such as  pest-resistant seeds, biostimulants and livestock breeds.

The World Bank Group is supporting the development of climate-smart agriculture and is committed to working with countries to increase productivity, improve resilience and reduce agricultural emissions. It has developed more than 10 Climate Smart Agriculture Investment Plans, offering financing of over USD 2.5 billion for climate-smart agriculture projects that are aligned with its objectives. Two examples include: 

  • Investment of USD 50 million in a Livestock and Dairy Development Project in Bangladesh
  • Supporting the design of the USD 50 million second phase of the Smallholder Agricultural Development Project in Lesotho through identifying potential climate change challenges and solutions.

Various green bonds have also been developed to support climate-smart agriculture in the Global South. For instance:

  • Bank Windhoek has issued green bonds for climate-smart agriculture in Namibia
  • The Nigerian sovereign bond includes investments in sustainable agriculture and climate-smart farming
  • The Trust Funds for Agricultural Development (FIRA) supports water efficiency and protected greenhouses in Mexico
  • The Sovereign Bond Issuance in Egypt supports the development of crop species that are resilient to salinity and temperature increase. 

The CGIAR, a global partnership linking international organisations concerned with food security, aims to improve the resilience of small-scale farmers to climate shocks through providing climate adaptation solutions through national innovation schemes. Examples include ‘climate-smart villages’, which identifies villages or regions that are likely to be badly affected by climate change and then connects community representatives and researchers to work together to identify climate-smart solutions.   

The African Development Bank Group and the International Fund for Agricultural Development (IFAD) have launched the ‘Mission 1 for 200’ initiative, which aims to “double agricultural productivity through the use of state-of-the-art, climate-smart technology and advice” and “build resilience by helping food systems and farmers adapt to climate change and reducing agriculture’s environmental impact and emissions”.

Organic farming 

The aim of organic farming is “to create integrated, humane, environmentally and economically sustainable production systems, which maximize reliance on farm-derived renewable resources and the management of ecological and biological processes and interactions, so as to provide acceptable levels of crop, livestock and human nutrition, protection from pests and disease, and an appropriate return to the human and other resources”. Increasing awareness of the negative impacts on inputs, such as pesticides, on human health and the environment has spurred public interest in organic products. It is suggested that organic agriculture has room to expand globally, and given its various sustainability benefits over conventional farming, such as improved soil and food quality, greater biodiversity, less pollution and greater social benefits, it could contribute greatly to feeding the world.      

Organic farming systems can promote food security by using minimal external inputs and promoting environmentally-friendly techniques. They are characterised by the following five features:

  • Respect for the environment and animals, such as through reduced pesticide pollution and lower nitrate leaching
  • Promotion of sustainable cropping methods, such as crop rotation and legume intercropping, as well as the promotion of crop and livestock diversity
  • Use of non-chemical fertilisers and pest/disease/weed control means, such as green fertilisers, compost and animal manures, natural pest control and no prophylactic antibiotics 
  • Production of high-quality foodstuffs, such as those with no pesticide residue 
  • Zero use of genetically modified crops.

There are various advantages of organic farming for small-scale producers, including: 

Some disadvantages include: 

  • Yields are approximately 25% lower than yields from conventional farms4Despite the lower yields, the economic profitability is around 22%-35% higher than conventional agriculture. 
  • It may not be possible to produce sufficient compost and green manures in certain regions due to landscape constraints
  • The average return on investment for farmers is around five years
  • Achieving organic certification requires around three years, and during this time farmers will need to produce organic products but will not be able to sell their products at premium and will also need to endure reduced yields at the same time
  • Higher labour costs5In certain regions, this could be viewed as an advantage, such as by promoting rural employment. 
  • Challenges with soil nutrient management.    

Compared to intensively-managed agriculture, organic farming tends to improve species richness and abundance, although there may not be a major difference between organic farms and small-scale farms made up of different agricultural fields and species. Organic farming has been found to have higher soil carbon levels, better soil quality and less soil erosion than conventional farms. Organic farming, on average, has a lower climate impact than conventional farming, whether considering the carbon footprint per land unit (43% fewer greenhouse gas emissions) or the carbon footprint per product unit (12% fewer greenhouse gas emissions). However, there are some examples of where organic farming performs less well than conventional farming:

Source: Our World in Data

As the chart above shows, while organic farming mostly performs better in certain impacts, such as greenhouse gas emissions, it performs less well in others, such as land use. For some impacts, the effects might be mixed – for example, energy use for producing vegetables in organic farming is higher because of certain alternative pesticides that may be used. The eutrophication (enriching a body of water with minerals and nutrients) potential in organic farming is high due to differences in the nutrient release of synthetic fertilisers versus manures. 

Regenerative agriculture

Regenerative agriculture has been broadly defined as “a system of farming principles and practices that increases biodiversity, enriches soils, improves watersheds and enhances ecosystem services”. It strongly emphasises the improvement of soil health and the restoration of degraded soils, which in turn enhances the quality of water and vegetation, improves land productivity and restores the carbon content of the soil. Another core feature of regenerative agriculture is the reversal of biodiversity loss. 

A wide variety of practices may be promoted under regenerative agriculture, as summarised in the table below:

Source: Regenerative Agriculture: An agronomic perspective

In terms of financing, in Brazil Rizoma-Agro has issued green bonds for regenerative agriculture, while Biotrop has issued green bonds worth BRL 100 million for regenerative agriculture. PepsiCo has issued a 10-year USD 1.25 billion green bond focused on investments into environmental sustainability, including regenerative agriculture.    

Agroecology

Agroecology is “the integrative study of the ecology of the entire food system, encompassing ecological, economic and social dimensions”. It offers a framework for supporting sustainable agriculture and food systems that is focused on three aspects: 

  • The scientific aspect, which uses modern ecological knowledge to design and manage sustainable farming ecosystems 
  • The practical aspect, which values the local, empirical and indigenous knowledge of farmers to develop innovative and effective farming practices 
  • The social change aspect, which advocates for changes to the food system that ensure food security for all. 

Rather than altering the practices of existing unsustainable agricultural systems, agroecology requires the complete transformation of food and agricultural systems. The way in which agroecological principles are applied will depend on the local context. 

The 10 Elements of Agroecology, which is a framework that was developed by the FAO and multiple stakeholders, offers a guideline: 

  • Diversification is key to agroecological transitions to ensure food security and nutrition while conserving, protecting and enhancing natural resources
  • Agricultural innovations respond better to local challenges when they are co-created through participatory processes
  • Building synergies enhances key functions across food systems, supporting production and multiple ecosystem services
  • Innovative agroecological practices produce more using less external resources
  • More recycling means agricultural production with lower economic and environmental costs
  • Enhanced resilience of people, communities and ecosystems is key to sustainable food and agricultural systems
  • Protecting and improving rural livelihoods, equity and social well-being is essential for sustainable food and agricultural systems
  • By supporting healthy, diversified and culturally appropriate diets, agroecology contributes to food security and nutrition while maintaining the health of ecosystems
  • Sustainable food and agriculture requires responsible and effective governance mechanisms at different scales, from local to national to global
  • Circular and solidarity economies that reconnect producers and consumers provide innovative solutions for living within our planetary boundaries while ensuring the social foundation for inclusive and sustainable development.
Source: International Fund for Agricultural Development

For a project to be considered agroecological, it should be:6This is according to the International Fund for Agricultural Development Agroecology Framework

  • Increasing resource use efficiency while reducing and/or substituting external inputs
  • Recycling water, nutrients, biomass and/or energy
  • Diversifying and integrating different farming sectors (various crops and/or animals)
  • Facilitating efficiency and recycling, spreading risks, increasing resilience and producing a greater variety of nutritious food.

The Scaling-up Agroecology Initiative is a UN-led platform that aims to support national agroecology processes through policy and technical capacity. The International Fund for Agricultural Development (IFAD) supports the initiative, and of the 207 IFAD-supported projects completed between 2018-2023, around 60% are implementing agroecological principles. The total investment in all IFAD projects in these years was USD 8.25 billion, though more financing was allocated to non-agroecological farming projects. Financing from the Adaptation for Smallholder Agriculture Programme (ASAP) and the Global Environment Facility (GEF) has been key in providing access to funds for agroecological practices – around 87% of projects with ASAP financing and 90% of projects with GEF financing entirely or partially promote agroecology. While the public sector is the primary financing source for both agroecological and non-agroecological IFAD, ASAP and GEF-supported projects, the private sector has played very little role in this financing, highlighting a key financing source to be developed.

Finance for small-scale farms in the Global South

IFAD is a UN-linked international financial institution focused on small-scale agriculture and supporting farmers through projects that provide small-scale farmers with access to finance, markets and technology, including via grants and low-interest loans. Together with finance and policy advisory organisation the Climate Policy Initiative (CPI), it released a report on the climate finance gap for small-scale farming. Climate finance is aimed at “reducing emissions and enhancing sinks of greenhouse gasses, and aims at reducing vulnerability and maintaining and increasing the resilience of human and ecological systems to negative climate change impacts”. The report found that 95% of climate finance for small-scale agriculture comes from the public sector, including from government donors, multilateral and bilateral development finance institutions (see the chart below).

Source: International Fund for Agricultural Development

The financial instruments used by the public sector mostly include grants (50%), followed by concessional (low cost) debt (33%) and non-concessional debt (16%). Of these grants, the majority (80%) were provided by governments, while concessional debt was largely issued by multilateral and bilateral development finance institutions. Multilateral development banks also provided the majority of the non-concessional debt. 

There are various impact-oriented funds aimed at small-scale agriculture, including: 

  • The Land Degradation Neutrality (LND) Fund, which is an “an impact investment fund blending resources from the public, private and philanthropic sectors to support achieving LDN through sustainable land management and land restoration projects implemented by the private sector”.
  • The Meloy Fund, which is an “impact investment fund focused on proving the triple bottom line viability of investing in fishing and seafood-related enterprises that will lead to better management and protection of these formerly under-appreciated and undervalued natural assets”.
  • &Green, which aims to “finance the delinking of major commodity supply chains from deforestation in a way that is commercially viable and replicable” through offering “innovative financial instruments that take away part of the risks of investing”.
  • Root Capital, which “provides credit and capacity building to small and growing agricultural businesses around the globe”.

Blended finance, which is “the strategic use of development finance and philanthropic funds to mobilise private capital flows to emerging and frontier markets”, is viewed as a finance solution for climate resilient and sustainable agriculture. Blended finance helps reduce both real and perceived risks in an investment, thereby facilitating private capital investment. Between 2014-2019, around 22% of blended finance transactions globally went to rural and smallholder farmers (see the chart below). The median transaction size for smallholder farmers during this period was USD 35 million, though the scale of these transactions has increased in recent years.

Source: Convergence

Blended finance is helping small-scale farmers through market initiatives such as Aceli Africa, which is supporting loans to agricultural small and medium sized enterprises in Africa. For instance, Aceli’s financial incentives helped Tanzania Commercial Bank provide loans for business to purchase cassava from smallholder farmers. Another example is the African Agricultural Capital Fund, which has made investments ranging from USD 250,000 to USD 2.5 million in small and medium sized agricultural businesses in Africa. 

The Commission on Sustainable Agriculture Intensification (CoSAI) commissioned a report that found that around USD 60 billion was spent each year on agricultural innovation in the Global South between 2010-2019, of which 60%-70% came from national governments, 20%-25% from the private sector (mostly related to the research and development and marketing of new products related to mechanisation, crop protection, and seed development and biotechnology), and 10%-20% from development partners, including institutional investors, bilateral and multilateral agencies, and international philanthropies.7Examples of innovation funding in the report included research into new seed varieties, training on new agroforestry practices, the adoption of agricultural policies such as fertiliser subsidy reforms, digital marketplaces for agricultural sales and purchases, and the maintenance and management of research institutes or infrastructure, such as the modernisation of slaughterhouses. Of this funding, less than 7% was directed at sustainable intensification specifically.

  • 1
    Small-scale farmers are typically those that produce food on up to two hectares of land in Asia and Africa and up to 15 hectares in Latin America. Small-scale farmers may or may not hold land titles.
  • 2
    Conventional pesticides are expensive for these farmers, who often do not have access to adequate protective clothing.
  • 3
    Ecosystem services are the basic services that are provided by the natural environment that offer benefits to humans, such as pollination
  • 4
  • 5
    In certain regions, this could be viewed as an advantage, such as by promoting rural employment.
  • 6
    This is according to the International Fund for Agricultural Development Agroecology Framework
  • 7
    Examples of innovation funding in the report included research into new seed varieties, training on new agroforestry practices, the adoption of agricultural policies such as fertiliser subsidy reforms, digital marketplaces for agricultural sales and purchases, and the maintenance and management of research institutes or infrastructure, such as the modernisation of slaughterhouses.

The impacts of El Niño on a warming planet

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Key points:

  • El Niño is a natural climate phenomenon, typically lasting 9-12 months, that has been linked to crop failures, more frequent wildfires and concurrent droughts, increased flood risk, disruptions to fisheries, elevated civil conflict and increased disease risk in various regions
  • Present forecasts predict an 84% chance of at least a moderate El Niño and a ±56% chance of a strong El Niño for 2023-2024
  • The first year that we see average temperatures exceed 1.5°C could be during El Niño. While this would not mean that the Paris Agreement target has been transgressed, it is a reminder that we are getting closer to this threshold    
  • The frequency and severity of El Niño events increased in the latter part of the 20th century, and climate change is projected to further increase both, as well as making these events more difficult to predict
  • El Niño involves complex interplay among various atmospheric phenomena, making its impacts difficult to predict. However, it is associated with some general weather trends around the world, including:
    • Increased rainfall and flooding risk in East Africa, northern Mexico, the southern US, Peru and Ecuador  
    • Elevated fire risk in Indonesia, Australia and the Amazon 
    • Drought conditions in India, southern Africa, the Philippines, Indonesia, the Amazon and Australia  
    • Warm conditions in Canada and the northern US
  • Countries and ecosystems are already experiencing impacts from climate change, such as heatwaves, droughts and floods, and El Niño is likely to make these impacts worse.

El Niño

First described by Peruvian fishermen in the late nineteenth century as warm ocean waters around Christmas time that disrupt fishing conditions, El Niño is a natural climate phenomenon in which sea surface temperatures in the tropical Pacific are warmer than average. Under normal (or neutral) atmospheric conditions, trade winds – the east-to-west winds that blow along the earth’s equator – transport warm water from South America to Asia, which is then replaced by cooler water from lower depths. This process, referred to as upwelling, brings nutrients to the surface water, creating fertile fishing grounds. During an El Niño event, the trade winds weaken, causing warm water to accumulate in the Pacific Ocean. By contrast, when the trade winds are strong, the opposite happens and more warm water is transported to Asia – called a La Niña event. These two opposing processes – El Niño and La Niña – make up the El Niño-Southern Oscillation (ENSO) cycle. 

In the past, ENSO events were described as Eastern-Pacific (EP) events, because the Eastern Pacific was where the maximum warming was located. However, the last four decades have seen an increase in the frequency of Central-Pacific (CP) events,1CP El Niño events are also referred to as “El Niño Modoki” and “warm pool El Niño”. where the maximum warming is located in the central equatorial Pacific. The characteristics and associated impacts of these two events differ.2EP ENSO has stronger El Niño events compared to La Niña events, whereas CP ENSO has stronger La Niña events compared to El Niño events.   

The latest El Niño forecast, issued in June this year by the National Oceanic and Atmospheric Administration, states that El Niño has started and is expected to gradually strengthen during the Northern Hemispheric winter of 2023-2024. There is a ±56% chance of a strong El Niño and an 84% chance of a moderate El Niño. This prediction comes after an unusually long La Niña event lasting three years came to an end earlier this year. This was linked to catastrophic flooding in South-east Asia and Australia, particularly in Pakistan, where flooding displaced around eight million people, as well as the most severe drought in recent history in the Horn of Africa, which has left millions of people displaced and at risk of starvation.

Impacts of El Niño

Though the effects were originally thought to be localised to the coastal regions of Peru and Ecuador, it is now known that the impacts of El Niño, as well as its cooler counterpart La Niña, are global and have been linked to crop failures, increased wildfire frequency, increased flood risk, heightened concurrent drought frequency, disruptions to fisheries, increased civil conflict and higher disease risk in various regions of the world.

El Niño and climate change

The occurrence of extreme El Niño and La Niña events has increased since the 1960s, and climate projections suggest the frequency of extreme ENSO events will increase in the future.3The IPCC AR6 WGI report states that “a robust increase in ENSO rainfall amplitude [used for defining extreme El Niños and La Niñas] is found particularly in SSP2‑4.5, SSP3‑7.0, and SSP5‑8.5… The changes in ENSO rainfall amplitude in the long-term future (2081–2100) relative to the recent past (1995–2014) are statistically significant at the 95% confidence [level]”.While climate models do not show consensus regarding changes in ENSO sea surface temperature variability, models that simulate extreme ENSO events do show large agreement. Some projections suggest a doubling of extreme El Niño events as global temperatures continue to rise.4The future period in the study included projections until 2090. CP El Niño events are expected to become more frequent with climate change, while EP events are projected to become more extreme. 

During the second half of the 20th century, various changes to the behaviour of ENSO were observed, including: 

  • An increase in the occurrence of CP El Niño events   
  • Increased frequency of more extreme El Niño and La Niña events  
  • Increased variability of both CP and EP ENSO events  
  • Changes in the origin of both CP and EP ENSO events since the 1970s from the western Pacific to the central and eastern Pacific. 

As ENSO is a naturally highly variable phenomenon, determining whether the characteristics of ENSO events since the 1950s are the result of human-caused global warming, or simply a reflection of this inherent variability, is not straightforward, partly because sea surface temperature records before 1950 are sparse and unreliable.5In the IPCC AR6 WGI report it states that “there is medium confidence that both ENSO amplitude and the frequency of high-magnitude events since 1950 are higher than over the period from 1850 and possibly as far back as 1400”. Estimates using paleoclimate proxy data – which can be found in coral fossils and tree rings, for example – suggest that ENSO variability intensified by around 25% during the latter part of the 20th century compared to pre-industrial times.6Paleo-reconstructions typically have large uncertainty. A study published earlier this year estimates that human-caused warming has led to approximately one additional CP El Niño event and two additional extreme El Niño events since 1980. Despite the uncertainties, there is a growing consensus that human-caused warming is at least partly responsible for the changes in ENSO variability since the 1960s.

Record high sea temperatures in April this year may also worsen the upcoming El Niño event. We are likely to see record-breaking temperatures with this year’s El Niño, which is occurring against a backdrop of a warming earth – the last eight years were the world’s hottest on record. The hottest of these was in 2016 during one of the strongest El Niño events on record, which saw unparalleled coral heat stress in the world’s oceans resulting in extensive coral bleaching and die-off. ‘Pulse heat stress’ events, such as El Niño, may compound climate change-related stresses on humans and other organisms, with potentially irreversible consequences.7For instance, the 1982/1983 ​​El Niño event led to the possible extinction of a coral species in Panama.

It is more likely than not that global average temperatures will temporarily exceed 1.5°C above pre-industrial levels for the first time in human history between 2023 and 2027.8A 66% chance of exceeding 1.5°C for one year, according to the World Meteorological Organisation’s Global Annual to Decade Climate Update. It is unlikely (33% chance) that the 5-year average temperature will remain above 1.5°C between 2023 and 2027.  During an extreme El Niño event, an extra 0.2°C could be added to the average temperature of the earth on top of elevated temperatures due to global warming. The first year that we see average temperatures exceed 1.5°C could be during El Niño. While this would not mean that the Paris Agreement target has been transgressed, it is a reminder that we are getting closer to this threshold.9Breaching the Paris Agreement target of 1.5°C of warming since pre-industrial times – a threshold seen as important for limiting the impacts of climate change on people and nature – would require several decades of average temperatures above 1.5°C.  

Countries and ecosystems are already experiencing climate change-induced impacts, such as heatwaves, droughts and floods, and El Niño is likely to make these impacts worse. It has also been suggested that continued global warming is making it increasingly difficult to predict El Niño events.

Regional impacts

Predicting whether an El Niño event will occur, or how intense it will be, is challenging, mainly because predictions need to consider changes in both the Pacific Ocean and the atmosphere. While the characteristics of every El Niño event are different, our understanding of ‘teleconnections’ – whereby a climatic pattern, such as El Niño, is correlated with weather patterns elsewhere in the world – can be used to make predictions about the possible impacts. The figure below shows the typical weather impacts of El Niño across the world.

Source: National Oceanic and Atmospheric Administration
Africa

In East Africa, El Niño conditions tend to result in wetter ‘short rains’ (the second rainy season in November and December), which can cause flooding. There is also a strong link between the Indian Ocean Dipole (IOD) – the Indian Ocean counterpart of El Niño and La Niña, in which there is a difference in sea surface temperatures between the western and eastern Indian Ocean – and El Niño. When there is a positive IOD and EP El Niño, wetter short rains are amplified. 

In southern Africa, drier than average conditions are expected under El Niño, resulting in decreased maize yields, while the opposite is anticipated in East Africa. In Kenya, the higher rainfall associated with the 2015-2017 El Niño cycle increased maize production by 17%, while drought conditions in southern Africa during the same period reduced maize yields by up to 50%, caused the death of around 634,000 cattle, and resulted in more than 20 million people needing humanitarian aid. By contrast, wheat yields in South Africa may benefit from El Niño. 

During and after El Niño events, cholera incidence has been found to increase threefold in El Niño-sensitive areas in East Africa due to higher rainfall.

India

For India, El Niño tends to weaken the monsoon rains and produce drier conditions, and experts warn that when an El Niño event follows from a La Niña year – as is the case in 2023 – the monsoon rains may be particularly low.10Though this is dependent on various factors, such as lower Eurasian snow cover, which creates warmer conditions on the subcontinent, thereby bringing more rain to India. An assessment of rainfall trends over 132 years in India shows that severe droughts in the region have always been during El Niño years. Additionally, a CP El Niño event impacts the monsoon more than an EP event, but if an EP event occurs, there is also a higher possibility of a positive IOD occurring, which brings drier conditions to the eastern Indian Ocean (in the region of India) but wetter conditions to the western Indian Ocean (in the region of eastern Africa).

Southeast Asia

In Java, Indonesia, El Niño tends to decrease rainfall. Decreased rainfall during El Niño periods has been linked to increased forest fires in Indonesia and reduced rice yields on Java. where more than 50% of the country’s rice is grown. Fires in Indonesia are more intense and prolonged under an EP El Niño, and southern Kalimantan has experienced more intense fires than southern Sumatra under all El Niño events. However, fires are shorter and less intense during El Niño phases when the IOD is negative or weakly positive.     

In the Philippines, El Niño is associated with a decrease in average rainfall and elevated drought conditions, particularly during December to May. The associated water shortages may negatively impact agricultural production in the region – the 2015/2016 El Niño event cost USD 327 million in agricultural production losses. In China, El Niño is linked to higher wintertime air pollution due to southerly winds that encourage the accumulation of particulates.

Europe

El Niño winters are associated with wetter conditions in southern Europe and colder, drier conditions in northern Europe.

Australia

In Australia, El Niño is expected to bring higher temperatures and fire risk, and lower rainfall. Australia is warming faster than some other regions on earth – being 1.4°C warmer than it was during pre-industrial times – potentially making it particularly vulnerable to the effects of El Niño.

North America

In the Northern US and Canada, El Niño is associated with warmer conditions, whereas in the southern US and northern Mexico, wetter, cooler conditions with increased flooding risk are expected. El Niño weakens Atlantic hurricane activity but increases Pacific hurricane activity. 

El Niño may reduce wheat yields in the US as well as maize yields in the southeastern US, while soybean yields may increase.  

South America

El Niño typically brings heavier rains and flooding risk to Ecuador, Peru and Uruguay, A CP El Niño brings drier conditions to the tropical Andes and northern South America, but wetter conditions to southeastern South America and the Peruvian Amazon. An EP El Niño is linked to higher rainfall in Ecuador and Peru and dry conditions in northeastern Brazil, the Amazon Basin and the Andean Plateau. Specifically, an EP El Niño is associated with reduced rainfall in northern, eastern and western Amazonia, with significant impacts on water and carbon cycling – whereby carbon atoms are cycled between the atmosphere, organisms and minerals on earth. During EP El Niño events, lower rainfall occurs across all seasons in the Amazon, turning the Amazon into a net carbon source as trees dry out and slow their growth. During CP El Niño events, reduced rainfall is only observed during the summer wet season. Increased drought may drive forest fires and biome transformation in the Amazon. Warmer, drier conditions in Colombia during El Niño have been linked to outbreaks of dengue fever and malaria.

El Niño may positively affect maize production in Argentina and Brazil, soybean and rice production in Brazil, and wheat production in Argentina due to cooler and wetter conditions. In Mexico, El Niño could reduce maize and wheat output.

  • 1
    CP El Niño events are also referred to as “El Niño Modoki” and “warm pool El Niño”.
  • 2
    EP ENSO has stronger El Niño events compared to La Niña events, whereas CP ENSO has stronger La Niña events compared to El Niño events.   
  • 3
    The IPCC AR6 WGI report states that “a robust increase in ENSO rainfall amplitude [used for defining extreme El Niños and La Niñas] is found particularly in SSP2‑4.5, SSP3‑7.0, and SSP5‑8.5… The changes in ENSO rainfall amplitude in the long-term future (2081–2100) relative to the recent past (1995–2014) are statistically significant at the 95% confidence [level]”.While climate models do not show consensus regarding changes in ENSO sea surface temperature variability, models that simulate extreme ENSO events do show large agreement.
  • 4
    The future period in the study included projections until 2090.
  • 5
    In the IPCC AR6 WGI report it states that “there is medium confidence that both ENSO amplitude and the frequency of high-magnitude events since 1950 are higher than over the period from 1850 and possibly as far back as 1400”.
  • 6
    Paleo-reconstructions typically have large uncertainty.
  • 7
    For instance, the 1982/1983 ​​El Niño event led to the possible extinction of a coral species in Panama.
  • 8
    A 66% chance of exceeding 1.5°C for one year, according to the World Meteorological Organisation’s Global Annual to Decade Climate Update. It is unlikely (33% chance) that the 5-year average temperature will remain above 1.5°C between 2023 and 2027. 
  • 9
    Breaching the Paris Agreement target of 1.5°C of warming since pre-industrial times – a threshold seen as important for limiting the impacts of climate change on people and nature – would require several decades of average temperatures above 1.5°C.
  • 10

Biogas and its role in the energy transition

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Key points

  • Reliance on biogas and biomethane as a decarbonisation solution should be limited to hard-to-abate sectors where there are currently no feasible, economic alternatives for emissions reduction (such as petrochemical production or industrial heating)
  • Use of biogas in electricity generation, heating and transportation should be limited given there are already cost effective options for electrification of end-use using renewable energy
  • Biogas’ potential to reduce agricultural emissions is limited to sources of emissions arising from manure and crop residuals, which contribute to a minority of agricultural emissions overall. The source and sustainability of feedstock is critical to the overall lifecycle emissions and costs
  • Biogas deployment should be carefully weighed against known limitations and risks, which include the impact of fugitive emissions, potentially limited availability of sustainable feedstock, high cost and reliance on public investment, and safety concerns.

What are biogas and biomethane?

Biogas is produced from the controlled decomposition of organic matter (through processes like anaerobic decomposition), where the gases that form as a result are captured. These gases are usually a mixture of methane (waste and agriculture account for roughly 60% of global methane emissions) and CO2, which are both potent greenhouse gases. Additional processes can be applied to remove the CO2 from biogas, leaving only methane, which is known as biomethane. For the purpose of this briefing, the term biogas is used to encompass both biogas and biomethane. 

Biogas can be a substitute for current uses of fossil fuel-based natural gas, ranging from electricity generation to heating – the IEA estimates that biogas has the potential to replace 20% of current demand for natural gas. Some argue that by capturing methane from waste and agricultural products and using it as a substitute for natural gas, biogas is a necessary renewable solution for limiting global warming to 1.5oC. This briefing examines the potential and limitations of using biogas for reducing global emissions.

Mitigation potential of biogas

Agricultural byproducts are the main source of biogas feedstock today. However, biogas feedstock is not the only valuable use of agricultural byproducts. For example, animal waste can be used as fertiliser.

Biogas can reduce emissions in two ways:

  • Mitigate methane and other greenhouse gas emissions in the agriculture sector, where livestock emissions represent roughly 32% of global methane emissions
  • Substitute the use of natural gas by producing methane from waste materials.

Using biogas for electricity generation and heating still requires methane to be combusted, which produces CO2, the greenhouse gas driving climate change more than any other. 

Therefore, the emissions benefit of biogas depend on:

  • The sustainability of its production method as a feedstock
  • The emission reduction potential compared to other low or zero-emission alternatives 
  • Feasibility and potential for uptake given the cost and availability of feedstock 
  • The net lifecycle emissions from the production of feedstock, including any potential leakages
  • Whether a high rate of carbon capture and storage is deployed if the biogas is combusted.

It is also worth noting that common technologies for producing biogas from manure management (such as anaerobic digestion) tend to be inefficient and often produce large amounts of CO2, which require processing to upgrade into biogas.

Biogas’ potential to mitigate agricultural emissions

Biogas’ potential to reduce agricultural emissions is limited to sources of emissions arising from manure and crop residuals, which contribute to a minority of agricultural emissions out of the five main sources: 

  • Enteric fermentation: 44.3% of agricultural emissions
  • Manure left on pasture and management: 23% of agricultural emissions
  • Crop residuals: 5.9% of agricultural emissions
  • Feed: 13.5% of agricultural emissions
  • Other emissions (land use change, energy use): 13.3% of agricultural emissions.

Therefore, capturing emissions from manure and crop residuals to produce biogas will, at best, address 28.9% of global agricultural emissions, leaving the majority of emissions unabated. And this is likely to be an overestimate given that more than 80% of the world’s farms are held by smallholders in developing countries with less than two hectares of land that meet the technical and financial requirements needed to install an anaerobic digester. Comparatively, US livestock farms need to meet the following criteria to be potential candidates for anaerobic digestion:

  • Minimum of 500 head of cattle, 2,000 hogs with anaerobic lagoons or liquid slurry manure management systems, or 5,000 hogs with deep-pit manure management systems
  • Minimum of 90% of manure is regularly collected.

Beyond using manure and crop residuals as sources of feedstock, biogas production requires farming energy crops, and this has been criticised by the IPCC for causing biodiversity loss, undermining food security and excessive water use, as well as creating the potential for temperature overshoot.

The REPower EU plan

In the RePower EU plan, the European Commission announced a target of 35 billion cubic metres (bcm) of production volume in Europe by 2030. This is a twelvefold increase of the current 3 bcm biogas (specifically biomethane) produced in the EU each year. 

An assessment by the Institute for Energy and Environmental Research (IFEU) for the European Climate Foundation of how much sustainable biogas could be produced in Europe found only 17 bcm could be produced by 2030. 

It found that, in order to achieve the 35 bcm biomethane target, the residues available for biogas production would not be sufficient and a considerable amount of crop-based biomass would have to be used. This would have considerable disadvantages. In a realistic scenario, around five to six million hectares of arable land would be required. This equals 5% of the arable land and 20% of the land used for wheat cultivation in the EU27. It would be more than the area that is used in the Ukraine for rapeseed production. Occupying land for biomethane production would thus lower the land availability for food production significantly.

Biogas as a substitute for fossil fuel-based natural gas

Most biogas produced today (64%) is used for electricity generation, predominantly in Europe and North America. Around 27% is used for heating in buildings. Acting as a substitute for fossil fuel natural gas can help avoid the current emissions impact of natural gas extraction, and its associated environmental impact. However, this substitution effect assumes that natural gas will continue to be used in electricity generation and heating. But viable alternatives such as renewable energy and widespread electrification already exist today. A study that evaluated the lifecycle environmental impacts of biogas electricity in comparison to other renewable alternatives looked at 11 environmental indicators (including emissions, human toxicity and ozone layer depletion) found that “biogas electricity can help reduce greenhouse gas (GHG) emissions relative to a fossil-intensive electricity mix; however, some other impacts increase. If mitigation of climate change is the main aim, other renewables have a greater potential to reduce GHG emissions.” 

In fact renewable energy is now the cheapest source of energy in most countries. Given the continued cost reductions in wind and solar and high implementation cost of biogas production, it is unlikely that biogas electricity generation will be competitive against renewable energy on a levelised cost of electricity (LCOE) basis.

There may be a limited role for biogas as a substitute for fossil fuel-based natural gas for hard-to-abate sectors such as petrochemical production and industrial heat, where there are fewer options for electrification using renewable energy. However, achieving the volume and cost reductions needed to supply biogas for these purposes is by no means a given.

Risks and limitations for deployment of biogas

Fugitive emissions reduce the benefits of biogas

The IPCC has found that fugitive emissions generated by biogas plants can reduce the potential benefit of biogas production from an emissions perspective. A 2022 study found that supply chains for biomethane and biogas release more than twice the amount of methane previously estimated by the International Energy Agency, with 62% of leaks originating from a small number of facilities. 

Another study examined 10 biogas plants in the UK and found that the rate of fugitive emissions reached a maximum of 9%, suggesting biogas plant methane emissions may account for up to 3.8% of total UK methane emissions. The research reached the conclusion that “the sustainability of biogas plants and the UK Net Zero Commitment may be jeopardised unless robust, consistent emission measurements and legal requirements are put into practice in the near future.”

High cost and reliance on subsidies

Biogas production and consumption require significant investment for:

  • the construction of biodigestion facility 
  • feedstock collection
  • processing
  • transport and conversion
  • application of carbon capture and storage.

The cost of each component is highly dependent on the location of feedstock and its ultimate end use. This means biogas production tends to be more economically feasible in countries where the location of the feedstock is close to the source of final conversion and use, and where there is already transportation infrastructure in place. As a result, biogas production barely exists in countries like Australia, and remains challenging to implement in other regions (such as Latin America, Africa or Southeast Asia). 

In Europe and the US, the high capital cost of installing biodigesters (around 70%-95% of total biogas costs) means significant subsidies are required to make projects financially feasible. A detailed geospatial analysis recently revealed that 40% of the amount that is technically available would still be uneconomic by 2050 without subsidies. In Germany, small plants have been found uneconomic, needing combinations of 50% of investment subsidised and EUR 11.50/MWh (USD 11.30/MWh) feed-in tariffs to make the projects economic. 

The application of carbon capture and storage to limit the emissions of carbon dioxide when biogas is burnt at its end use would also increase costs significantly. Given alternatives that exist to reduce waste and agricultural emissions, and limited situations where biogas can be a credible substitute for hard-to-abate sectors, the public investment in biogas should be balanced against other investment opportunities in decarbonisation.

Safety concerns

Many biogas facilities operate at small and medium scales, and they are not subject to the same safety standards as large-scale operations. Major hazards from biogas facilities include:

  • Explosions and fires
    • When inappropriately mixed, air and methane is explosive
    • Ammonia has explosive and flammable properties
    • Hydrogen sulfide is extremely flammable
  • Toxicity
    • Hydrogen sulfide is highly toxic. 

A study suggests that between 1994-2015, 169 accidents occurred in the biogas sector, 12% of which could be classified as serious. One hundred and sixty-three of these occurred in Europe, mostly in Germany, which has the highest number of biogas plants. Of these, 53% resulted in fire, 40% resulted in explosion and 7% were related to toxic release.

Alternatives for reducing agricultural emissions

There are cost-effective alternatives for reducing emissions in agriculture and waste management that are ready for deployment. For example, transitioning to sustainable agriculture methods as well as a shift to a more sustainable food system are cost effective ways to reduce existing emissions in the agriculture industry. The IPCC found that economic mitigation options (less than USD 100 per tonne of CO2 reduced) such as improving soil management, agroforestry and livestock management have the mitigation potential of 4.1 GtCO2e each year. Shifting to sustainable healthy diets, reducing food waste and other demand side measures have the mitigation potential of 2.2 GtCO2e each year.

Loss and Damage in the Sundarbans

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Key points:

  • The Sundarban region, home to 7.2 million of the world’s most vulnerable people and the largest single mangrove forest in the world, is increasingly at threat from catastrophic impacts of climate change
  • Climate change is contributing to the absence of employment opportunities, the destruction of property from extreme weather events and the loss of vital mangroves and land from sea level rise. With homes and livelihoods under threat, many are left with no choice but to migrate elsewhere
  • The increasing scale and frequency of climate impacts mean the limits of adaptation have already been reached in many cases. The most affected argue that the extensive loss and damage needs to be addressed by those responsible with the financial means to do so.

What are the Sundarbans?

The Sundarbans are a cluster of low-lying islands in the Bay of Bengal, spread across India and Bangladesh. The region is recognised internationally for its unique biodiversity and ecological importance – including the single largest mangrove forest in the world, encompassing a total area of 10,200 km2.  

The Sundarbans ecosystem offers a wide range of vital ecological services, including cyclone protection for millions of people, wildlife habitat, food and natural resource provision, and carbon sequestration. It is also home to about 7.2 million people (4.5 million in India and 2.7 million in Bangladesh), including some of South Asia’s poorest and most vulnerable communities. Around half the population lives below the poverty line.

Due to a lack of employment opportunities, most are dependent on the land and natural resources that are increasingly being depleted by climate change. Most rely on subsistence agriculture, supplemented with fishing, crab and honey collection. Millions are unable to meet their basic nutritional requirements, leading to health issues such as anaemia, malnutrition and childhood stunting. At the same time, climate impacts are exacerbated by other factors, such as poverty, lack of livelihood options, reliance on land, uneven land ownership and limited government support.

The Sundarbans were declared a reserve forest before the partition of India in 1875, and UNESCO declared the Indian and Bangladesh portions of the Sundarbans World Heritage Sites in 1987 and 1997, respectively. The region is also recognised under the Ramsar Convention on Wetlands. Despite this recognition, including conservation obligations under international conventions and treaties, the Sundarbans are under threat from climate change, along with a combination of natural factors and human impacts.

Climate impacts in the Sundarbans

Land mass is declining year by year

In 2015-16, the total area of the Sundarbans had shrunk  by 210 km2 since 1967, and by 451 km2 since 1904. This declining trend holds true whether the Indian and Bangladesh portions of the Sundarbans are considered separately or grouped together. The main reason is the surrounding sea level, which is rising more than twice as fast as the global average. Satellite imagery shows the sea level has risen in the Sundarbans by an average of three centimetres a year over the past twenty years, and the area has lost almost 12% of its shoreline in the last forty. In addition to sea level rise, a gradual reduction in sediment flow from rivers to the Sundarban region has resulted in loss of land mass. 

Due to these factors, the rate of retreat of coastlines is as high as 40m a year for some of the islands, which will disappear completely within the next 50–100 years at the current rate. Already some islands have been submerged and it is predicted that many more will vanish if sea level rise maintains its current pace.

Salinisation is threatening agriculture and health

Where land is not yet lost, frequent flooding with salty water from rising sea levels and extreme weather events renders affected land unproductive. Increasing water and soil salinity are also caused by climate-induced changes in temperature and rainfall, along with reduced freshwater flows from the Himalayas in the dry season. In the last 40 years, approximately 25% of glacial ice has been lost in the mountain range, posing a significant risk to stable and reliable freshwater supplies to major rivers, such as the Ganges and Brahmaputra, that flow into the Sundarbans. 

In the Sundarban region, water and soil salinity has increased dramatically, with projections that many parts of the region will reach near ocean-level salinity by 2050. In Bangladesh, soil salinity increased six times, and up to fifteen times in certain areas, from 1984 to 2014. The salinisation of soil ruins crops and devastates farmer livelihoods. Research estimates a one metre increase in sea level would cause losses as high as USD 597 million in agriculture from salinity-induced land degradation. Some villages no longer support agriculture due to recurrent salt water inundation. When households are no longer able to grow crops on land due to lack of access or salty soil, they are unable to engage in subsistence farming and are exposed to the cash economy, increasing their risk of food insecurity.

Progressive salinisation of rivers and groundwater has also resulted in the decline of available fresh drinking water, with numerous adverse effects on mother-child health, including dehydration, hypertension, prenatal complications and increased infant mortality. Collection of data from drinking wells in the Indian Sundarbans found that 17 out of 50 wells sampled contained salinity levels unsuitable for drinking. Increased saline water levels also cause high blood pressure and fever, as well as respiratory and skin diseases. A vulnerability assessment of Mousuni Island in the Sundarban region found that 80% of the villagers experienced skin disease caused by salty water. Additionally, 42% of households suffered infectious diseases, such as malaria and dengue fever, during flooding. Under high emissions scenarios, climate change is expected to make the prevalence of disease, particularly water-borne illnesses, even higher.

Mangroves and biodiversity are being depleted

Mangrove forests are a crucial natural blockade against cyclones, storm surges and tides, and sustain the high levels of biodiversity in the region. One study estimates that between 2000 and 2020, 110 km2 of mangroves disappeared from the reserve forest of the Indian Sundarbans due to erosion. While 81km2 of mangroves were gained through plantation and regeneration, the gains were all outside the existing mangrove forest. Another study looking at the coverage of mangrove forests between 1975 and 2020 found that mangrove forests have been decreasing in density by an estimated annual rate of 1.3%.

Researchers also observed a deterioration in the health of mangrove forests over the last twenty years due to increased salinity, temperature rise and rainfall reduction in pre and post-monsoon periods. While mangroves are known for their resilience, they are sensitive to changes in the salinity of water and soils, which is already resulting in shifts away from high-value timber species towards more salt-tolerant mangrove species. This is reducing the quality and overall availability of timber stocks, with implications for those relying on the forest for their livelihoods. Researchers estimate that there has been a loss of USD 3.3 billion in ecosystem services of the Sundarban Biosphere Reserve during the last 30 years, over 80% of which is provided by mangroves.

In a changing climate, it is expected that the Sundarbans landscape will undergo significant fragmentation, causing habitat loss for many endangered species, including tigers and venomous snakes, and this is increasing the risk of human-wildlife conflicts in the region. Sea level rise is resulting in habitat loss for many terrestrial and amphibian species. Habitats for freshwater fish are also shrinking as water becomes more salty, threatening many small, indigenous freshwater species. This has adverse impacts on the livelihoods of fishermen, as well as on human health as fish is a critical source of protein and nutrients in the Sundarbans. For example, in regions with high levels of fish species loss, chronic and acute malnutrition among mothers and children is higher than the thresholds set by the World Health Organization for public health emergencies.

Extreme weather events are more frequent and severe

While the Sundarban region has always been affected by cyclones and extreme weather events, the rate and intensity of these events are increasing. In the last 23 years, the area has witnessed 13 supercyclones. In the Bay of Bengal along the Sundarbans, the occurrences of cyclones increased by 26% between 1881 and 2001. Additionally, research has shown there has been a significant rise in the frequency of very severe cyclones in the post-monsoon season from 2000 to 2018. Scientists project an increase of about 50% in the frequency of post-monsoon cyclones by 2041-2060. 

The rise in cyclone frequency and severity is in part attributed to the increase in sea surface temperature, which rose in the Indian Sundarbans at 0.5°C per decade from 1980 through to 2007 – around eight times higher than the globally-observed warming rate of 0.06°C per decade. Land surface temperature in Sundarban region has already increased about 1°C over the past century and is projected to warm by up to 3.7°C by 2100.

Due to the low elevation of the Sundarbans and reduced protection from mangroves, cyclones can cause catastrophic damage. Four major cyclones have hit the Sunderbans in the last three years, killing nearly 250 people and causing losses of nearly USD 20 billion. Cyclone Amphan in 2020 was estimated to have destroyed 28% of the Indian Sundarban region and caused USD 12 billion of damage. The Cyclone displaced 2.4 million people in India and 2.5 million people in Bangladesh. While many returned soon afterwards, damage to more than 2.8 million homes and lack of evacuation centres resulted in homelessness and prolonged displacement for many thousands.

Following Amphan, the government estimates over 100,000 farmers experienced heavy losses as salt water in fields and ponds killed off fish and rendered fields uncultivable. With hundreds and thousands of extra mouths to feed, conflicts between humans and tigers spiked as islanders began venturing deep into the forests in search of fish, crab, honey and firewood.

Livelihoods are being hit hard

About five million people are dependent on the Sundarbans for their livelihoods. According to the World Bank, almost 80% of households in the Sundarbans pursue livelihoods that involve inefficient agriculture, fishing and aquaculture production methods. Dependence on the land and natural resources paired with a lack of alternative employment opportunities means livelihoods are extremely vulnerable to changing climatic conditions.

Salinisation is threatening agriculture. Fishermen are impacted by the decline in fish populations. Forest-based livelihoods are adversely impacted by changes in the composition of mangrove species, which is reducing the value of standing timber and honey production. A study of three villages in the Indian Sundarbans found that 62% of the workforce has lost their original livelihoods and have been forced to rely on much more uncertain incomes. 

Even though the impacts of climate change put their livelihoods at greater risk, some households continue to live in vulnerable locations due to high land prices and a lack of employment opportunities elsewhere. Due to a lack of job opportunities, others need to migrate to seek out employment, temporarily or sometimes permanently. 

Young men and women have had to leave for nearby cities, or even states over 1,000 kilometres away. There they face a precarious existence as daily wage labourers and contract workers at construction sites and factories. Some estimates suggest that roughly 60% of the male workforce in the Indian Sundarbans has migrated. Migration has also increased the poverty of the population left behind since it takes considerable time for low-skilled migrant family members to save sufficient funds to send back home.

Migration as a last resort

An estimated 1.5 million people will have to be permanently relocated outside the Sundarbans because sea level rise will make it impossible for them to live there or earn a livelihood. As climate change is responsible for their forced migration, these people are climate refugees – however, the term is not formally recognised internationally.  Additionally, extreme poverty both arises from and contributes to their vulnerability to environmental hazards. 

Over the past 25 years, four islands in the Indian Sundarbans – Bedford, Lohachara, Kabasgadi and Suparibhanga – have already disappeared, causing 6,000 families to become displaced. Lohachara became well-known as the first inhabited island in the world to disappear. Neighbouring Ghoramara is already half underwater. Once home to 40,000 people, the 2011 census counted only 5,000 people still struggling on the island. 

Many of those displaced relocated to nearby Sagar island with the aid of government programmes in the 1980s and 1990s. However, with a population of 200,000 and growing, and with the island having shrunk by a sixth of its original size, land and resources are being severely depleted. One case study calculated the total value of damage to 31 households forced to move from inundated areas of the Sundarbans to the island of Sagar at Rs 6,0742,225 crore (USD 700,000), 98% of which was due to loss of land assets. 

Back in 2002, it was estimated that climate change would displace over 69,000 people from the Sundarbans by 2020. In 2018, about 60,000 people had already migrated from the region.

Why adaptation is not enough

Climate adaptation is the process of adjusting to current or expected effects of climate change. However, it is clear that adapting to some impacts of climate change will not be possible and, in some cases, the limits of adaptation have already been reached. 

A key adaptation measure is the construction of storm surge walls and embankments. However, even with these measures, the loss and damage inflicted by a few hours’ battering by waves, winds, and storm surges during a cyclone can undo the gains from many years of measures to prevent flooding. After Cyclone Aila in 2009 destroyed 778 km of embankments in the Sundarbans, it cost Rs 5,032 crore (USD 670 million) to rebuild them, only for them to be breached again ten years later by Cyclone Amphan. One Sundarban village, after embankments to hold back the rising sea collapsed during Cyclone Aila, attempted three times to build sea walls, all of which collapsed against the power of the sea. 

Another adaptation approach is the introduction of salt-resistant crops. This has been met with some success, but may prove to be a temporary fix, with hurdles such as the availability of seeds, knowledge of farming and relatively low yields. 

Adaptation practices can also exacerbate and accelerate the ecological damage caused. For example, increasing salinity levels prevent the cultivation of rice or other crops, causing some to shift towards shrimp farming, which requires salt water and can be more profitable. However, the conversion of land to shrimp farms further accelerates the salinisation of water while profits often only benefit private investors. Workers – primarily women – receive little income and suffer health issues, such as infections, problems with eyesight and skin disease.

For the people of the Sundarbans, lives depend upon the land on which they live, produce food and sustain their livelihoods. Some inhabitants have already had to relocate multiple times. In the words of one resident: “People are resilient, but how much resilience can they have?” The outlook is bleak for the Sundarbans, with proposals that ‘managed retreat’ – the planned migration away from vulnerable regions over time – may be the only viable option.

Why financing for Loss and Damage is needed

Loss and damage is a term used to describe how climate change is already causing serious and, in many cases, irrevocable impacts around the world – particularly in vulnerable communities. According to the most recent assessment of climate impacts from the Intergovernmental Panel on Climate Change (IPCC), loss and damage can broadly be split into two categories – economic losses involving “income and physical assets”, and non-economic losses, including “mortality, mobility and mental wellbeing losses”. 

For the people of the Sundarbans, the economic and non-economic losses, such as loss of land, livelihood, mortality, health, culture, are beyond what the region can afford. According to a 2009 study, the annual costs of the environmental damage and health issues caused by climate change are estimated at Rs 1290 crore annually (USD 250 million) – equivalent to 10% of the Sundarbans GDP in 2009. 

The Sundarbans bear little responsibility for global emissions (for example, the whole country of Bangladesh is accountable only for only 0.56% of global emissions), but are forced to suffer the consequences. Alongside many other developing nations and vulnerable communities, the region argues strongly that it should not be forced to pay for the excessive loss and damage already incurred, and anticipated in the future.

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