Can Polar Stratospheric Clouds Explain Arctic Amplification?
Climate models underestimate the magnitude of Arctic warming in past warm climates, like the early Cretaceous and Paleogene periods, implying that certain physical processes might be missing or poorly represented. Previous studies suggest that a large increase in wintertime Arctic polar stratospheri...
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American Meteorological Society
2023
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ftunswworks:oai:unsworks.library.unsw.edu.au:1959.4/unsworks_83777 2024-06-02T08:00:31+00:00 Can Polar Stratospheric Clouds Explain Arctic Amplification? Dutta, D Sherwood, SC Jucker, M Gupta, AS Meissner, KJ 2023-04-15 http://hdl.handle.net/1959.4/unsworks_83777 https://doi.org/10.1175/JCLI-D-22-0497.1 unknown American Meteorological Society http://purl.org/au-research/grants/arc/FL150100035 http://hdl.handle.net/1959.4/unsworks_83777 https://doi.org/10.1175/JCLI-D-22-0497.1 metadata only access http://purl.org/coar/access_right/c_14cb CC-BY https://creativecommons.org/licenses/by/4.0/ urn:ISSN:0894-8755 urn:ISSN:1520-0442 Journal of Climate, 36, 8, 2313-2332 13 Climate Action anzsrc-for: 0401 Atmospheric Sciences anzsrc-for: 0405 Oceanography anzsrc-for: 0909 Geomatic Engineering journal article http://purl.org/coar/resource_type/c_6501 2023 ftunswworks https://doi.org/10.1175/JCLI-D-22-0497.1 2024-05-07T23:55:04Z Climate models underestimate the magnitude of Arctic warming in past warm climates, like the early Cretaceous and Paleogene periods, implying that certain physical processes might be missing or poorly represented. Previous studies suggest that a large increase in wintertime Arctic polar stratospheric clouds (PSCs) might have promoted Arctic amplification through additional greenhouse warming. High methane concentrations in warm climates might have increased stratospheric water vapor providing favorable conditions for PSCs. However, methane concentrations in past warm climates are extremely uncertain. Here, we revisit the PSC hypothesis by exploring PSC changes under very high methane levels, 43 preindustrial carbon dioxide, and strong polar-amplified surface warming, using a whole-atmosphere model with fully interactive chemistry. We find that with polar-amplified warming there is a large increase in Arctic outgoing longwave radiation (OLR) that reduces as the methane concentration is increased. PSCs increase monotonically with methane concentration. A large radiative cooling and an increase in water vapor in the stratosphere increases Arctic PSCs, which follow a power law with respect to relative humidity. Using a two-way partial radiative perturbation technique, we show that the OLR reduction due to PSCs is similar to the direct radiative forcing of methane for high methane levels. Thus, we find that PSCs could play an important role in Arctic warming in a warmer-than-present-day climate, but only if methane levels were higher than suggested by previous modeling studies for past warm climates. Article in Journal/Newspaper Arctic UNSW Sydney (The University of New South Wales): UNSWorks Arctic Journal of Climate 36 8 2313 2332 |
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Open Polar |
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UNSW Sydney (The University of New South Wales): UNSWorks |
op_collection_id |
ftunswworks |
language |
unknown |
topic |
13 Climate Action anzsrc-for: 0401 Atmospheric Sciences anzsrc-for: 0405 Oceanography anzsrc-for: 0909 Geomatic Engineering |
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13 Climate Action anzsrc-for: 0401 Atmospheric Sciences anzsrc-for: 0405 Oceanography anzsrc-for: 0909 Geomatic Engineering Dutta, D Sherwood, SC Jucker, M Gupta, AS Meissner, KJ Can Polar Stratospheric Clouds Explain Arctic Amplification? |
topic_facet |
13 Climate Action anzsrc-for: 0401 Atmospheric Sciences anzsrc-for: 0405 Oceanography anzsrc-for: 0909 Geomatic Engineering |
description |
Climate models underestimate the magnitude of Arctic warming in past warm climates, like the early Cretaceous and Paleogene periods, implying that certain physical processes might be missing or poorly represented. Previous studies suggest that a large increase in wintertime Arctic polar stratospheric clouds (PSCs) might have promoted Arctic amplification through additional greenhouse warming. High methane concentrations in warm climates might have increased stratospheric water vapor providing favorable conditions for PSCs. However, methane concentrations in past warm climates are extremely uncertain. Here, we revisit the PSC hypothesis by exploring PSC changes under very high methane levels, 43 preindustrial carbon dioxide, and strong polar-amplified surface warming, using a whole-atmosphere model with fully interactive chemistry. We find that with polar-amplified warming there is a large increase in Arctic outgoing longwave radiation (OLR) that reduces as the methane concentration is increased. PSCs increase monotonically with methane concentration. A large radiative cooling and an increase in water vapor in the stratosphere increases Arctic PSCs, which follow a power law with respect to relative humidity. Using a two-way partial radiative perturbation technique, we show that the OLR reduction due to PSCs is similar to the direct radiative forcing of methane for high methane levels. Thus, we find that PSCs could play an important role in Arctic warming in a warmer-than-present-day climate, but only if methane levels were higher than suggested by previous modeling studies for past warm climates. |
format |
Article in Journal/Newspaper |
author |
Dutta, D Sherwood, SC Jucker, M Gupta, AS Meissner, KJ |
author_facet |
Dutta, D Sherwood, SC Jucker, M Gupta, AS Meissner, KJ |
author_sort |
Dutta, D |
title |
Can Polar Stratospheric Clouds Explain Arctic Amplification? |
title_short |
Can Polar Stratospheric Clouds Explain Arctic Amplification? |
title_full |
Can Polar Stratospheric Clouds Explain Arctic Amplification? |
title_fullStr |
Can Polar Stratospheric Clouds Explain Arctic Amplification? |
title_full_unstemmed |
Can Polar Stratospheric Clouds Explain Arctic Amplification? |
title_sort |
can polar stratospheric clouds explain arctic amplification? |
publisher |
American Meteorological Society |
publishDate |
2023 |
url |
http://hdl.handle.net/1959.4/unsworks_83777 https://doi.org/10.1175/JCLI-D-22-0497.1 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
urn:ISSN:0894-8755 urn:ISSN:1520-0442 Journal of Climate, 36, 8, 2313-2332 |
op_relation |
http://purl.org/au-research/grants/arc/FL150100035 http://hdl.handle.net/1959.4/unsworks_83777 https://doi.org/10.1175/JCLI-D-22-0497.1 |
op_rights |
metadata only access http://purl.org/coar/access_right/c_14cb CC-BY https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1175/JCLI-D-22-0497.1 |
container_title |
Journal of Climate |
container_volume |
36 |
container_issue |
8 |
container_start_page |
2313 |
op_container_end_page |
2332 |
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1800744546950184960 |