Spatial Patterns of Crop Yield Change by Emitted Pollutant

Abstract

Field measurements and modeling have examined how temperature, precipitation, and exposure to carbon dioxide (CO 2 ) and ozone affect major staple crops around the world. Most prior studies, however, have incorporated only a subset of these influences. Here we examine how emissions of each individual pollutant driving changes in these four factors affect present‐day yields of wheat, maize (corn), and rice worldwide. Our statistical modeling indicates that for the global mean, climate and composition changes have decreased wheat and maize yields substantially whereas rice yields have increased. Well‐mixed greenhouse gasses drive most of the impacts, though aerosol‐induced cooling can be important, particularly for more polluted area including India and China. Maize yield losses are most strongly attributable to methane emissions (via both temperature and ozone). In tropical areas, wheat yield losses are primarily driven by CO 2 (via temperature), whereas in temperate zones other well‐mixed greenhouse gases dominate. Rice yields increase in tropical countries due to a larger impact from CO 2 fertilization plus aerosol‐induced cooling than losses due to CO 2 ‐induced warming and impacts of non‐CO 2 gasses, whereas there are net losses in temperate zones driven largely by methane and other non‐CO 2 gasses. Though further work is needed, particularly on the effects of aerosol changes and on nutritional impacts, these results suggest that crop yields over coming decades will be strongly influenced by changes in non‐CO 2 greenhouse gasses, ozone precursors, and aerosols and that these should be taking into account in plant‐level models and when examining linkages between climate change mitigation and sustainable development.

Temporal and spatial distribution of health, labor, and crop benefits of climate change mitigation in the United States

“…Impacts on labor are evaluated based on both exposure to air pollution and heat ( 15 , 34 , 36 ), the latter for specific professions where heat exposure is both difficult to avoid and impactful. Agricultural impacts include responses to temperature and precipitation and to changes in CO 2 and surface ozone ( 37 ). The analysis includes projected changes in population, baseline health, and gross domestic product but does not include changes in the workforce or cultivated areas ( SI Appendix ).…”

Magnitude, trends, and impacts of ambient long-term ozone exposure in the United States from 2000 to 2015

“…For example, two CTM-based studies estimated 2005 respiratory-related premature mortalities in the USA using the same relative risk function (Jerrett et al, 2009), yet yielded results that differed by ∼ 3× (i.e., 13 000 vs. 38 000; Zhang et al, 2018;Lelieveld et al, 2013). While CTMs accurately reproduce many features of atmospheric chemistry (Shindell et al, 2013;Hu et al, 2018), one important issue associated with CTM-based impact assessments is that CTMs are consistently biased high when predicting O 3 concentrations (e.g., Schnell et al, 2015;Travis et al, 2016;Yan et al, 2016;Seltzer et al, 2017, Porter et al, 2017Guo et al, 2018). Such biases can influence estimates of impacts and are often amplified by nonlinear concentrationresponse functions .…”

Significant Reductions in Crop Yields From Air Pollution and Heat Stress in the United States

“…Future warming would also go along with rising atmospheric fertilization may partially offset the warming damages. A recent study indicated that in temperate regions, emissions would cause a substantial short‐term increase in agricultural production due to the instantaneous response of atmospheric concentrations to emissions, but the net effect attenuates within a decade or so to near‐zero as the fertilization is canceled by the impacts of ‐induced climate change (Shindell et al., 2019). Greater atmospheric concentration induced by future fossil fuel combustion brings an offset of global warming on crop yields, and should be integrated into future analysis.…”