Impact of Stratospheric Aerosol Injection on the East Asian Winter Monsoon

22 views

Skip to first unread message

ayesha iqbal

unread,

Feb 3, 2023, 5:45:21 AM2/3/23

to geoengi...@googlegroups.com

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2022GL102109

Authors

Zhaochen Liu, Xianmei Lang, Jiapeng Miao, Dabang Jiang

First published: 24 January 2023

https://doi.org/10.1029/2022GL102109

Citation: Liu, Z., Lang, X., Miao, J., & Jiang, D. Impact of Stratospheric Aerosol Injection on the East Asian Winter Monsoon. Geophysical Research Letters, e2022GL102109.

Abstract

Stratospheric aerosol injection (SAI) has been proposed as a potential measure to alleviate global warming; however, uncertainties exist in its regional climate impacts. This study investigates the influence of the SAI on the East Asian winter monsoon (EAWM) by analyzing the G6sulfur simulation from the Geoengineering Model Intercomparison Project. Our results show that the SAI intensifies the Siberian high and Aleutian low, enhances the low-level northerly winds along the coast of East Asia and deepens the East Asian trough during 2080–2099, reversing the weakening of EAWM in high-emission Shared Socioeconomic Pathway scenario (SSP5-8.5). Comparison between the G6sulfur and SSP5-8.5 simulations indicates that, the SAI-induced strong cooling in the central equatorial Pacific excites a poleward-propagating Rossby wave train and strengthen the EAWM. Meanwhile, the negative vorticity advection in the middle troposphere and the radiative cooling over the Siberian high region caused by SAI also intensify the EAWM.

Key Points

Stratospheric aerosol injection in G6sulfur offsets half of winter warming and 80% of precipitation increase in SSP5-8.5 over East Asia
The poleward Rossby wave train induced by stratospheric aerosol injection strengthens the East Asian winter monsoon
Both the 500-hPa negative vorticity advection and tropospheric radiative cooling over the Siberian high region enhance the Siberian high

Plain Language Summary

Atmospheric greenhouse gas concentrations have increased since the industrial revolution, and they have profoundly affected the climate system and human society. According to a proposed solar radiation modification method, stratospheric aerosol injection (SAI) can partly offset greenhouse gas-induced warming by scattering solar radiation, but its regional climate impacts are not well understood. In this study, we focus on how the East Asian winter monsoon, one of the most active climate systems in boreal winter, responds to the SAI using simulations from six state-of-the-art climate models. We find that the SAI significantly enhances the East Asian winter monsoon in the late 21st century. The propagation of atmospheric wave caused by SAI-induced sea surface temperature change is the primary C.