Contributions of World Regions to the Global Tropospheric Ozone Burden Change From 1980 to 2010

• Published in: Geophysical research letters Vol. 48; no. 1; pp. 2659 - n/a
• Main Authors: Zhang, Yuqiang, West, J. Jason, Emmons, Louisa K., Flemming, Johannes, Jonson, Jan Eiof, Lund, Marianne T., Sekiya, Takashi, Sudo, Kengo, Gaudel, Audrey, Chang, Kai‐Lan, Nédélec, Philippe, Thouret, Valérie
• Format: Journal Article
• Language: English
• Published: American Geophysical Union 16-01-2021
• Subjects: Atmospheric and Oceanic Physics; Physics
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2020GL089184

We investigate the contributions of emission changes from 10 world regions, as well as the global methane concentration change, on the global tropospheric ozone burden change from 1980 to 2010. The modeled global tropospheric ozone burden has increased by 28.1 Tg, with 26.7% (7.5 Tg) of this change attributed to the global methane increase. Southeast Asia (5.6 Tg) and South Asia (4.0) contribute comparably to the global ozone burden change as East Asia (5.6), even though NOx emission increases in each region are less than one‐third of those in East Asia, highlighting the greater sensitivity of global ozone to these regions. Emission decreases from North America, Europe, and Former Soviet Union have led to ozone burden decreases of 2.8, 1.0, and 0.3 Tg. The greater sensitivity of the global ozone burden to emission changes in tropical and subtropical regions emphasizes the importance of controlling emissions in these regions for global ozone.
Plain Language Summary
The global tropospheric ozone burden is highly sensitive to emission changes in tropical and subtropical regions, due to high temperature, strong sunlight, and convection which are favorable for ozone production and accumulation. Through model sensitivity simulations, we show that emission increases in Southeast Asia, South Asia, and East Asia contribute over half of the global tropospheric ozone burden increase from 1980 to 2010. Southeast Asia and South Asia contribute about as much to the ozone increase as East Asia, even though emission increases were much smaller from these regions, showing the high ozone sensitivity in these regions.
Key Points
Tropospheric ozone burden increased from 1980 to 2010, driven mainly by increases in emissions from Southeast Asia, East Asia, and South Asia, as well as global methane concentration increases
Among regions, the greatest ozone burden influence came from Southeast Asia despite smaller emission increases, highlighting the much greater sensitivity for this region