Air Pollution Impacts on Global Crop Yields

Air Pollution Impacts on Global Crop Yields
Colette Heald, Associate Professor, Department of Civil & Environmental Engineering

Period of performance: 

September 2016 to August 2018

Abstract: 

Growing populations are exerting tremendous pressure on the global food supply. Environmental stresses put food security at even greater risk. Ozone air pollution has been shown to extensively damage crops at a cost of billions to the agricultural sector, yet our understanding of the air pollution impacts on food production is incomplete. To date, no study has examined the global impact of particulate atmospheric pollution on crop yields. Particulate matter (PM) is the leading environmental cause of premature mortality, responsible for many of the dramatic air pollution events seen in cities. By scattering and absorbing solar radiation, PM has two effects on plants (1) it reduces total solar radiation reaching the surface, reducing plant productivity, and (2) it increases the fraction of diffuse radiation, which can be more effectively used by the entire plant canopy, thereby increasing plant productivity. There is a critical need to examine these effects on crop yields at a global scale, under realistic local conditions. The objective of this project is to provide the first comprehensive estimate of food production risks associated with air pollution. We will combine global modeling tools with both statistical and mechanistic descriptions of crop response to estimate the impact of particulate air pollution on both present-day and 2050 crop yields. Particulate pollution may act to reinforce or counteract the damaging effects of ozone pollution, depending on the local environment; we will contrast these two effects in this project. This analysis will provide vital new insights into the food security risks associated with air pollution and the need for associated local scale crop adaptation.