Agriculture: A Source and Sink of Greenhouse Gas Emissions

The United Nations projects that our global population could increase to 9.7 billion by 2050. An additional two billion mouths to feed over a 30-year period.

As our climate changes and our population grows, so does the challenge of building climate resilient agri-food systems. Agricultural production is increasingly jeopardized by heat waves, water scarcity, drought, and extreme weather. Further, our agricultural landscapes are shifting as the demands of increased residential and commercial development reduce the amount of farmland in some areas and warmer climates provoke its expansion in other areas, exacerbating land use change and the release of carbon dioxide from newly ploughed soils. The challenge ahead of us is to proactively address this mounting pressure to adapt agricultural production to climate change effects and societal demands, so that it can produce enough food for all, while reducing its net greenhouse gas emissions.

In Canada, the agriculture sector has experienced increased impacts due to climate change. For example, the flooding and landslides in British Columbia in 2021 resulted in the largest ever agricultural disaster in B.C.'s history. Reports estimated that the floods caused about $285 million in damages in the agricultural sector, and long-lasting impacts on provincial food security.

At the same time, Canada’s agriculture sector contributes 8.2% of total national greenhouse gas emissions. Calculated outside of this contribution, croplands in Canada are a net carbon sink, yet they also contribute to land use conversion of forests and grasslands. The complex relationship that agriculture has with climate change – as a source and sink of greenhouse gas emissions – makes identifying solutions that create net positive outcomes for food, climate, people, and our environment extremely challenging.

For Canada, the agriculture sector is well positioned to face this challenge and be a global leader in low carbon agricultural production, as innovation along agri-food supply chains is accelerated to increase efficiencies and as farmers continue to adopt beneficial management practices such as improved nutrient management and cover crops to reduce greenhouse gas emissions from production and enhance carbon sinks in soils.

Not Just a Challenge for Canada

Agricultural production around the world is impacted by climate change. For example:

• Australia's agriculture sector has increasingly experienced rising temperatures, drought and wildfires. According to the Australian Government, the average temperature has increased by 1.4˚C since 1910, with the greatest changes felt since 1950. Due to these drier conditions, farms are at risk of experiencing a greater frequency of negative profit years and are therefore actively responding by adopting beneficial management practices to improve climate resilience and secure profits.  
• In Europe, climate change impacts have led to reduced harvests in southern regions, higher production costs, lower quantity, and poorer quality of agricultural products. Increased temperature is forecasted to impact crop productivities in the southern regions (such as southern Europe) by up to 50%, which is why on-farm adaptation and knowledge mobilization among farmers is key to improve farm productivity as the effects of climate change increase.
• In the U.S., increased climate disasters and temperatures may result in reduced crop yields. More extreme temperatures and precipitation can also prevent crops from growing. Droughts in some regions will likely cause increased reliance on irrigation and water-management systems. Lastly, increased temperatures could also cause an increase in invasive species and pests that can stress or damage crops and livestock.

The most severe impacts of climate change are felt in developing regions. By 2030, Southern Africa and South Asia are expected to be the two regions in the world whose crop production is most affected by climate change. The World Bank found that with warming of about 2˚C, crop yields across sub-Saharan Africa may decrease by 10% by the 2050s. If additional warming occurs (which is possible without significant action), this may cause crop yields to decrease by up to 15% or 20%. Hunger already affects approximately 240 million African people daily, and with warming even below 2˚C, the number of people experiencing food insecurity is expected to increase.

Recognizing that agriculture production and farmers’ livelihoods are increasingly under threat from the effects of climate change, building climate resilience within agri-food systems is a vital part of the discussions at COP27 in Egypt.

Through the multi-stream Natural Climate Solutions Fund, Canada has created the Agricultural Climate Solutions program. Under this program, the Living Laboratories initiative supports farmers, scientists, and other sector partners to co-develop, test, and monitor management practices on working farms with the aim of reducing Canada’s environmental footprint and enhancing climate resilience. Programs such as this support the development of Canada’s agriculture sector, working to reduce its emissions while still providing a secure flow of food for domestic and international markets.

At COP27, global leaders will look to further their efforts on agriculture and climate, with a discussion on producing food in climate smart and sustainable ways, enhancing the resilience of agricultural production, reducing food loss and waste across harvesting, transportation, and consumption stages, and re-shaping food demand.

Further Action Needed

Action is required to elevate both the adaptation capacity of agri-food systems to the effects of climate change, and the climate change mitigation potential of agricultural production.

Mitigating climate change in the agriculture sector can be achieved by adopting practices that enhance carbon storage in soils, such as cover crops, reduced tillage, and diverse crop rotations on croplands and rotational grazing, silvopasture, and legume integration on grasslands. Novel technologies and innovations can also improve livestock feeding and fertilizer application efficiency to reduce methane and nitrous oxide emissions, and improve the measurement of carbon in soils to inform further action. Agriculture can also play an important role in the transition to clean fuel and energy, through the use and production of renewable energy, including biomass, geothermal, wind and/or solar on farms and ranches. Such solutions can be costly, and increases in financial support and partnerships will be needed to reduce agricultural-based greenhouse gas emissions at scale.

The agriculture sector will also need to ensure that infrastructure, operations, and equipment is climate resilient. This may also include adapting planting cycles and species to accommodate shifts in weather patterns. Farmers have long been adapting to changes in climate and weather, however financing and capacity building is needed to support the sector in scaling its climate change adaptation efforts, and to recover from climate change impacts when they do occur.

WSP is helping clients in agriculture to develop decarbonization roadmaps, and tackle opportunities such as increasing the amount of carbon stored in soils. We also work with communities and local governments to implement measures that support resilient urban food systems and reduce emissions from agricultural processes and the transportation of food.