Climate change, air pollution and food security in Asia

Background/Question/Methods

Agricultural ecosystems in the Monsoon Asia region, feeding approximately 60% of the world’s population, have been playing an important role in enhancing food security globally. A range of studies (i.e. field experiments, remote sensing monitoring and ecosystem modeling) show that the vulnerability of agricultural production has substantially compounded due to unprecedented environmental changes such as climate change and air pollution in this region. In particular, worsening tropospheric ozone pollution and large-scale climate extreme events (i.e. flooding and droughts) have caused major impacts on the structure and functioning of agricultural ecosystems through changing the water, carbon and nitrogen dynamics, and thus have threatened the food security and agricultural sustainability. However, the magnitude, temporal and spatial patterns of agricultural production in responses to climate change, air pollution and other environmental factors, and the underlying mechanisms are still far from certain. This has hindered policy-makers to design detailed measures to mitigate and adapt food production systems to future climate change. Fully understanding the role of agricultural systems in the context of global change requires integrating multiple methods at scales ranging from field to continental from a system perspective. Here, we applied an integrated ecosystem model DLEM-Ag (the agricultural module of Dynamic Land Ecosystem Model), which combined the current understanding from field observations/experiments, remote sensing monitoring, inventory, and process-based modeling, and regional database to investigate the variations of crop production and yield in responses to the long-term climate variability/change, climate extreme events and tropospheric ozone pollution. We aim to quantitatively probe the underlying mechanisms of interactions among climate change, air pollution and food security in this region and provide potential adaptation strategies to policy-makers for future environmental change.

Results/Conclusions

The preliminary results show that in the Monsoon Asia region historical climate variability/change controlled the annual variations of crop production and yield and climate extreme events such as droughts significantly reduced crop production and yield, while the fertilizer application and ozone pollution continuously increased or reduced the crop production and yield. The results suggest that improving air quality and optimizing land management practices could partly offset the adverse impacts of climate variability/change and air pollution on agricultural ecosystems, though environmental problems and agronomic practices varied across different regions and countries.