Changes in global food consumption increase GHG emissions despite efficiency gains along global supply chains
Yanxian Li, Honglin Zhong, Yuli Shan, Ye Hang, Dan Wang, Yannan Zhou, Klaus Hubacek
Abstract
Greenhouse gas (GHG) emissions related to food consumption complement production-based or territorial accounts by capturing carbon leaked through trade. Here we evaluate global consumption-based food emissions between 2000 and 2019 and underlying drivers using a physical trade flow approach and structural decomposition analysis. In 2019, emissions throughout global food supply chains reached 30 ±9% of anthropogenic GHG emissions, largely triggered by beef and dairy consumption in rapidly developing countries—while per capita emissions in developed countries with a high percentage of animal-based food declined. Emissions outsourced through international food trade dominated by beef and oil crops increased by ~1 Gt CO2 equivalent, mainly driven by increased imports by developing countries. Population growth and per capita demand increase were key drivers to the global emissions increase (+30% and +19%, respectively) while decreasing emissions intensity from land-use activities was the major factor to offset emissions growth (−39%). Climate change mitigation may depend on incentivizing consumer and producer choices to reduce emissions-intensive food products. Using a physical trade flow approach and structural decomposition analysis, this study estimates consumption-based greenhouse gas emissions throughout food supply chains over 2000–2019, revealing overall trends and five underlying drivers.