TY - JOUR

T1 - Global Perspective of Drought Impacts on Ozone Pollution Episodes

AU - Lei, Yadong

AU - Yue, Xu

AU - Liao, Hong

AU - Zhang, Lin

AU - Zhou, Hao

AU - Tian, Chenguang

AU - Gong, Cheng

AU - Ma, Yimian

AU - Cao, Yang

AU - Seco, Roger

AU - Karl, Thomas

AU - Potosnak, Mark

N1 - Funding Information: This work was jointly supported by the National Natural Science Foundation of China (grant no. 41975155) and Jiangsu Science Fund for Distinguished Young Scholars (grant no. BK20200040). R.S. acknowledges grants RYC2020-029216-I and CEX2018-000794-S funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”. We would like to thank the editor and four anonymous reviewers for their constructive comments which helped improve the quality of the paper. Publisher Copyright: © 2022 American Chemical Society. All rights reserved.

PY - 2022

Y1 - 2022

N2 - Ozone (O3) pollution threatens global public health and damages ecosystem productivity. Droughts modulate surface O3through meteorological processes and vegetation feedbacks. Unraveling these influences is difficult with traditional chemical transport models. Here, using an atmospheric chemistry-vegetation coupled model in combination with a suite of existing measurements, we investigate the drought impacts on global surface O3and explore the main driving processes. Relative to the mean state, accelerated photochemical rates dominate the surface O3enhancement during droughts except for eastern U.S. and western Europe, where reduced stomatal uptakes make comparable contributions. During 1990-2012, the simulated frequency of O3pollution episodes in western Europe decreases greatly with a negative trend of -5.5 ± 6.6 days per decade following the reductions in anthropogenic emissions if meteorology is fixed. However, such decreased trend is weakened to -2.1 ± 3.8 days per decade, which is closer to the observed trend of -2.9 ± 1.1 days per decade when year-to-year meteorology is applied because increased droughts alone offset 43% of the effects from air pollution control. Our results highlight that more stringent controls of O3precursors are necessary to mitigate the higher risks of O3pollution episodes by more droughts in a warming world.

AB - Ozone (O3) pollution threatens global public health and damages ecosystem productivity. Droughts modulate surface O3through meteorological processes and vegetation feedbacks. Unraveling these influences is difficult with traditional chemical transport models. Here, using an atmospheric chemistry-vegetation coupled model in combination with a suite of existing measurements, we investigate the drought impacts on global surface O3and explore the main driving processes. Relative to the mean state, accelerated photochemical rates dominate the surface O3enhancement during droughts except for eastern U.S. and western Europe, where reduced stomatal uptakes make comparable contributions. During 1990-2012, the simulated frequency of O3pollution episodes in western Europe decreases greatly with a negative trend of -5.5 ± 6.6 days per decade following the reductions in anthropogenic emissions if meteorology is fixed. However, such decreased trend is weakened to -2.1 ± 3.8 days per decade, which is closer to the observed trend of -2.9 ± 1.1 days per decade when year-to-year meteorology is applied because increased droughts alone offset 43% of the effects from air pollution control. Our results highlight that more stringent controls of O3precursors are necessary to mitigate the higher risks of O3pollution episodes by more droughts in a warming world.

KW - chemistry-vegetation model

KW - drought

KW - meteorological processes

KW - ozone pollution

KW - vegetation feedbacks

U2 - 10.1021/acs.est.1c07260

DO - 10.1021/acs.est.1c07260

M3 - Journal article

C2 - 35298883

AN - SCOPUS:85127423950

VL - 56

SP - 3932

EP - 3940

JO - Environmental Science & Technology

JF - Environmental Science & Technology

SN - 0013-936X

IS - 7

ER -