% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Fadnavis:864733, author = {Fadnavis, Suvarna and Müller, Rolf and Kalita, Gayatry and Rowlinson, Matthew and Rap, Alexandru and Li, Jui-Lin Frank and Gasparini, Blaž and Laakso, Anton}, title = {{T}he impact of recent changes in {A}sian anthropogenic emissions of ${SO}\<sub\>2\</sub\>$ on sulfate loading in the upper troposphere and lower stratosphere and the associated radiative changes}, journal = {Atmospheric chemistry and physics}, volume = {19}, number = {15}, issn = {1680-7324}, address = {Katlenburg-Lindau}, publisher = {EGU}, reportid = {FZJ-2019-04404}, pages = {9989 - 10008}, year = {2019}, abstract = {Convective transport plays a key role in aerosol enhancement in the upper troposphere and lower stratosphere (UTLS) over the Asian monsoon region where low-level convective instability persists throughout the year. We use the state-of-the-art ECHAM6–HAMMOZ global chemistry–climate model to investigate the seasonal transport of anthropogenic Asian sulfate aerosols and their impact on the UTLS. Sensitivity simulations for SO2 emission perturbation over India $(48 \%$ increase) and China $(70 \%$ decrease) are performed based on the Ozone Monitoring Instrument (OMI) satellite-observed trend, rising over India by $∼4.8 \%$ per year and decreasing over China by $∼7.0 \%$ per year during 2006–2017. The enhanced Indian emissions result in an increase in aerosol optical depth (AOD) loading in the UTLS by 0.61 to $4.17 \%$ over India. These aerosols are transported to the Arctic during all seasons by the lower branch of the Brewer–Dobson circulation enhancing AOD by $0.017 \%$ to $4.8 \%.$ Interestingly, a reduction in SO2 emission over China inhibits the transport of Indian sulfate aerosols to the Arctic in summer-monsoon and post-monsoon seasons due to subsidence over northern India. The region of sulfate aerosol enhancement shows significant warming in the UTLS over northern India, south China (0.2±0.15 to 0.8±0.72 K) and the Arctic (∼1±0.62 to 1.6±1.07 K). The estimated seasonal mean direct radiative forcing at the top of the atmosphere (TOA) induced by the increase in Indian SO2 emission is −0.2 to −1.5 W m−2 over northern India. The Chinese SO2 emission reduction leads to a positive radiative forcing of ∼0.6 to 6 W m−2 over China. The decrease in vertical velocity and the associated enhanced stability of the upper troposphere in response to increased Indian SO2 emissions will likely decrease rainfall over India.}, cin = {IEK-7}, ddc = {550}, cid = {I:(DE-Juel1)IEK-7-20101013}, pnm = {244 - Composition and dynamics of the upper troposphere and middle atmosphere (POF3-244)}, pid = {G:(DE-HGF)POF3-244}, typ = {PUB:(DE-HGF)16}, UT = {WOS:000480315800002}, doi = {10.5194/acp-19-9989-2019}, url = {https://juser.fz-juelich.de/record/864733}, }