High-Resolution Maps Detail Global Cropland Emissions and Mitigation Strategies

A recent study published in Nature Climate Change presents high-resolution maps that detail global cropland greenhouse gas emissions, offering insights for targeted mitigation strategies. The research, led by Mario Herrero, professor of global development at Cornell University, synthesizes data from various sources to map emissions down to approximately 10 kilometers, categorizing them by crop type and emission source.

The study reveals that in 2020, croplands emitted the equivalent of 2.5 gigatons of carbon dioxide, with East Asia and the Pacific regions contributing about half of these emissions. South Asia, Europe, and Central Asia collectively accounted for 30%. Four crops—rice, maize, oil palm, and wheat—were responsible for nearly 75% of these emissions, with rice alone accounting for 43%. Key emission sources included drained peatlands for palm oil production (35%), flooded rice paddies (35%), and synthetic fertilizers in high-production areas (23%).

The findings underscore the need for tailored mitigation strategies. The authors suggest that controlled rewetting of peatlands, changes in rice paddy management, and optimized fertilizer use could significantly reduce emissions in specific regions. Herrero emphasized the importance of local action, noting that the maps provide crucial subnational analysis to identify mitigation opportunities, which is vital given limited mitigation funds.

The study also highlights a correlation between high food production and emissions, suggesting that mitigation planning should consider productivity. First author Peiyu Cao noted that linking food production to emissions helps assess the efficiency of production systems, indicating that regions with low emissions but also low food production, such as parts of Africa, could focus on improving productivity while maintaining low emissions. Conversely, high-production regions like Asia might prioritize emission reductions while sustaining productivity.

This research provides a comprehensive synthesis of data necessary for calculating greenhouse gas emissions by country and production system, facilitating the development of precision mitigation strategies.