Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics
It has been suggested that increased stratospheric sulfate aerosol loadings following large, low latitude volcanic eruptions can lead to wintertime warming over Eurasia through dynamical stratosphere-troposphere coupling. We here investigate the proposed connection in the context of hypothetical fut...
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ftcopernicus:oai:publications.copernicus.org:acpd89720 2023-05-15T17:29:27+02:00 Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics Banerjee, Antara Butler, Amy H. Polvani, Lorenzo M. Robock, Alan Simpson, Isla R. Sun, Lantao 2020-11-09 application/pdf https://doi.org/10.5194/acp-2020-965 https://acp.copernicus.org/preprints/acp-2020-965/ eng eng doi:10.5194/acp-2020-965 https://acp.copernicus.org/preprints/acp-2020-965/ eISSN: 1680-7324 Text 2020 ftcopernicus https://doi.org/10.5194/acp-2020-965 2020-11-16T17:22:15Z It has been suggested that increased stratospheric sulfate aerosol loadings following large, low latitude volcanic eruptions can lead to wintertime warming over Eurasia through dynamical stratosphere-troposphere coupling. We here investigate the proposed connection in the context of hypothetical future stratospheric sulfate geoengineering in the Geoengineering Large Ensemble simulations. In those geoengineering simulations, we find that stratospheric circulation anomalies that resemble the positive phase of the Northern Annular Mode in winter is a distinguishing climate response which is absent when increasing greenhouse gases alone are prescribed. This stratospheric dynamical response projects onto the positive phase of the North Atlantic Oscillation, leading to associated side-effects of this climate intervention strategy, such as continental Eurasian warming and precipitation changes. Seasonality is a key signature of the dynamically-driven surface response. We find an opposite response of the North Atlantic Oscillation in summer, when no dynamical role of the stratosphere is expected. The robustness of the wintertime forced response stands in contrast to previously proposed volcanic responses. Text North Atlantic North Atlantic oscillation Copernicus Publications: E-Journals |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
It has been suggested that increased stratospheric sulfate aerosol loadings following large, low latitude volcanic eruptions can lead to wintertime warming over Eurasia through dynamical stratosphere-troposphere coupling. We here investigate the proposed connection in the context of hypothetical future stratospheric sulfate geoengineering in the Geoengineering Large Ensemble simulations. In those geoengineering simulations, we find that stratospheric circulation anomalies that resemble the positive phase of the Northern Annular Mode in winter is a distinguishing climate response which is absent when increasing greenhouse gases alone are prescribed. This stratospheric dynamical response projects onto the positive phase of the North Atlantic Oscillation, leading to associated side-effects of this climate intervention strategy, such as continental Eurasian warming and precipitation changes. Seasonality is a key signature of the dynamically-driven surface response. We find an opposite response of the North Atlantic Oscillation in summer, when no dynamical role of the stratosphere is expected. The robustness of the wintertime forced response stands in contrast to previously proposed volcanic responses. |
format |
Text |
author |
Banerjee, Antara Butler, Amy H. Polvani, Lorenzo M. Robock, Alan Simpson, Isla R. Sun, Lantao |
spellingShingle |
Banerjee, Antara Butler, Amy H. Polvani, Lorenzo M. Robock, Alan Simpson, Isla R. Sun, Lantao Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics |
author_facet |
Banerjee, Antara Butler, Amy H. Polvani, Lorenzo M. Robock, Alan Simpson, Isla R. Sun, Lantao |
author_sort |
Banerjee, Antara |
title |
Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics |
title_short |
Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics |
title_full |
Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics |
title_fullStr |
Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics |
title_full_unstemmed |
Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics |
title_sort |
robust winter warming over eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics |
publishDate |
2020 |
url |
https://doi.org/10.5194/acp-2020-965 https://acp.copernicus.org/preprints/acp-2020-965/ |
genre |
North Atlantic North Atlantic oscillation |
genre_facet |
North Atlantic North Atlantic oscillation |
op_source |
eISSN: 1680-7324 |
op_relation |
doi:10.5194/acp-2020-965 https://acp.copernicus.org/preprints/acp-2020-965/ |
op_doi |
https://doi.org/10.5194/acp-2020-965 |
_version_ |
1766123568881467392 |