Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments
The national and global restrictions in response to the COVID-19 pandemic led to a sudden, albeit temporary, emission reduction of many greenhouse gases (GHGs) and anthropogenic aerosols, whose near-term climate impact were previously found to be negligible when focusing on global- and/or annual-mea...
Published in: | Atmospheric Chemistry and Physics |
---|---|
Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2023
|
Subjects: | |
Online Access: | https://doi.org/10.5194/acp-23-877-2023 https://doaj.org/article/46236a253b5d4f209acc711616c6eeb8 |
id |
ftdoajarticles:oai:doaj.org/article:46236a253b5d4f209acc711616c6eeb8 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:46236a253b5d4f209acc711616c6eeb8 2023-05-15T13:15:06+02:00 Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments N. L. S. Fahrenbach M. A. Bollasina 2023-01-01T00:00:00Z https://doi.org/10.5194/acp-23-877-2023 https://doaj.org/article/46236a253b5d4f209acc711616c6eeb8 EN eng Copernicus Publications https://acp.copernicus.org/articles/23/877/2023/acp-23-877-2023.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-23-877-2023 1680-7316 1680-7324 https://doaj.org/article/46236a253b5d4f209acc711616c6eeb8 Atmospheric Chemistry and Physics, Vol 23, Pp 877-894 (2023) Physics QC1-999 Chemistry QD1-999 article 2023 ftdoajarticles https://doi.org/10.5194/acp-23-877-2023 2023-01-22T01:32:34Z The national and global restrictions in response to the COVID-19 pandemic led to a sudden, albeit temporary, emission reduction of many greenhouse gases (GHGs) and anthropogenic aerosols, whose near-term climate impact were previously found to be negligible when focusing on global- and/or annual-mean scales. Our study aims to investigate the monthly scale coupled climate-and-circulation response to regional, COVID-19-related aerosol emission reductions, using the output from 10 Earth system models participating in the Covid model intercomparison project (CovidMIP). We focus on January–February and March–May 2020, which represent the seasons of largest emission changes in sulfate ( SO 2 ) and black carbon ( BC ). During January–February (JF), a marked decrease in aerosol emissions over eastern China, the main emission region, resulted in a lower aerosol burden, leading to an increase in surface downwelling radiation and ensuing surface warming. Regional sea-level pressure and circulation adjustments drive a precipitation increase over the Maritime Continent, embedded in a negative Pacific Decadal Oscillation (PDO)- and/or El Niño–Southern Oscillation (ENSO)-like response over the Pacific, in turn associated with a northwestward displacement and zonal shrinking of the Indo-Pacific Walker cell. Remote climate anomalies across the Northern Hemisphere, including a weakening of the Siberian High and Aleutian Low, as well as anomalous temperature patterns in the northern mid-latitudes, arise primarily as a result of stationary Rossby wave trains generated over East Asia. The anomalous climate pattern and driving dynamical mechanism reverse polarity between JF and MAM (March–May) 2020, which is shown to be consistent with an underlying shift of the dominant region of SO 2 emission reduction from eastern China in JF to India in MAM. Our findings highlight the prominent role of large-scale dynamical adjustments in generating a hemispheric-wide aerosol climate imprint even on short timescales, which are largely consistent ... Article in Journal/Newspaper aleutian low Directory of Open Access Journals: DOAJ Articles Pacific Atmospheric Chemistry and Physics 23 2 877 894 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Physics QC1-999 Chemistry QD1-999 |
spellingShingle |
Physics QC1-999 Chemistry QD1-999 N. L. S. Fahrenbach M. A. Bollasina Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
The national and global restrictions in response to the COVID-19 pandemic led to a sudden, albeit temporary, emission reduction of many greenhouse gases (GHGs) and anthropogenic aerosols, whose near-term climate impact were previously found to be negligible when focusing on global- and/or annual-mean scales. Our study aims to investigate the monthly scale coupled climate-and-circulation response to regional, COVID-19-related aerosol emission reductions, using the output from 10 Earth system models participating in the Covid model intercomparison project (CovidMIP). We focus on January–February and March–May 2020, which represent the seasons of largest emission changes in sulfate ( SO 2 ) and black carbon ( BC ). During January–February (JF), a marked decrease in aerosol emissions over eastern China, the main emission region, resulted in a lower aerosol burden, leading to an increase in surface downwelling radiation and ensuing surface warming. Regional sea-level pressure and circulation adjustments drive a precipitation increase over the Maritime Continent, embedded in a negative Pacific Decadal Oscillation (PDO)- and/or El Niño–Southern Oscillation (ENSO)-like response over the Pacific, in turn associated with a northwestward displacement and zonal shrinking of the Indo-Pacific Walker cell. Remote climate anomalies across the Northern Hemisphere, including a weakening of the Siberian High and Aleutian Low, as well as anomalous temperature patterns in the northern mid-latitudes, arise primarily as a result of stationary Rossby wave trains generated over East Asia. The anomalous climate pattern and driving dynamical mechanism reverse polarity between JF and MAM (March–May) 2020, which is shown to be consistent with an underlying shift of the dominant region of SO 2 emission reduction from eastern China in JF to India in MAM. Our findings highlight the prominent role of large-scale dynamical adjustments in generating a hemispheric-wide aerosol climate imprint even on short timescales, which are largely consistent ... |
format |
Article in Journal/Newspaper |
author |
N. L. S. Fahrenbach M. A. Bollasina |
author_facet |
N. L. S. Fahrenbach M. A. Bollasina |
author_sort |
N. L. S. Fahrenbach |
title |
Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments |
title_short |
Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments |
title_full |
Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments |
title_fullStr |
Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments |
title_full_unstemmed |
Hemispheric-wide climate response to regional COVID-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments |
title_sort |
hemispheric-wide climate response to regional covid-19-related aerosol emission reductions: the prominent role of atmospheric circulation adjustments |
publisher |
Copernicus Publications |
publishDate |
2023 |
url |
https://doi.org/10.5194/acp-23-877-2023 https://doaj.org/article/46236a253b5d4f209acc711616c6eeb8 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
aleutian low |
genre_facet |
aleutian low |
op_source |
Atmospheric Chemistry and Physics, Vol 23, Pp 877-894 (2023) |
op_relation |
https://acp.copernicus.org/articles/23/877/2023/acp-23-877-2023.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-23-877-2023 1680-7316 1680-7324 https://doaj.org/article/46236a253b5d4f209acc711616c6eeb8 |
op_doi |
https://doi.org/10.5194/acp-23-877-2023 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
23 |
container_issue |
2 |
container_start_page |
877 |
op_container_end_page |
894 |
_version_ |
1766266968448434176 |