The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter
The interdecadal Pacific oscillation (hereafter termed IPV, using "variability" in lieu of "oscillation") and the Atlantic multidecadal oscillation (hereafter AMV, similar to IPV) are regulators of global mean temperature, large-scale atmospheric circulation, regional temperature...
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ftcdlib:oai:escholarship.org/ark:/13030/qt7c98r35b 2023-05-15T13:14:55+02:00 The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter Elsbury, D Peings, Y Saint-Martin, D Douville, H Magnusdottir, G 4193 - 4213 2019-01-01 application/pdf https://escholarship.org/uc/item/7c98r35b unknown eScholarship, University of California qt7c98r35b https://escholarship.org/uc/item/7c98r35b CC-BY CC-BY Journal of Climate, vol 32, iss 14 Annular mode Teleconnections Extreme events Pacific-North American pattern oscillation Stratosphere-troposphere coupling Climate variability Mental Health Atmospheric Sciences Oceanography Geomatic Engineering Meteorology & Atmospheric Sciences article 2019 ftcdlib 2021-10-11T17:15:26Z The interdecadal Pacific oscillation (hereafter termed IPV, using "variability" in lieu of "oscillation") and the Atlantic multidecadal oscillation (hereafter AMV, similar to IPV) are regulators of global mean temperature, large-scale atmospheric circulation, regional temperature and precipitation, and related extreme events. Despite a growing recognition of their importance, the combined influence of these modes of lowfrequency sea surface temperature (SST) variability remains elusive given the short instrumental record and the difficulty of coupled climate models to simulate them satisfactorily. In this study, idealized simulations with two atmospheric global climate models (AGCMs) are used to show a partial cancellation of the North Pacific atmospheric response to positive IPV (i.e., deeper Aleutian low) by the concurrent positive phase of the AMV. This effect arises from a modulation of the interbasin Walker circulation that weakens deep convection in the western Pacific and the associated Rossby wave train into the northern extratropics. The weaker Aleutian low response is associated with less upward wave activity flux in the North Pacific; however, the associated stratospheric jet weakening is similar to when the +IPV alone forces the vortex, as additional upward wave activity flux over Siberia makes up the difference. While comparable warming of the polar stratosphere is found when the positiveAMVis included with the positive IPV, the downward propagation of the stratospheric response is significantly reduced, which has implications for the associated surface temperature extremes. The robust anticorrelation between the positive IPV and positive AMV signals over the North Pacific and their lack of additivity highlight the need to consider the IPV-AMV interplay for anticipating decadal changes in mean climate and extreme events in the Northern Hemisphere. Article in Journal/Newspaper aleutian low Siberia University of California: eScholarship Pacific |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
unknown |
topic |
Annular mode Teleconnections Extreme events Pacific-North American pattern oscillation Stratosphere-troposphere coupling Climate variability Mental Health Atmospheric Sciences Oceanography Geomatic Engineering Meteorology & Atmospheric Sciences |
spellingShingle |
Annular mode Teleconnections Extreme events Pacific-North American pattern oscillation Stratosphere-troposphere coupling Climate variability Mental Health Atmospheric Sciences Oceanography Geomatic Engineering Meteorology & Atmospheric Sciences Elsbury, D Peings, Y Saint-Martin, D Douville, H Magnusdottir, G The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter |
topic_facet |
Annular mode Teleconnections Extreme events Pacific-North American pattern oscillation Stratosphere-troposphere coupling Climate variability Mental Health Atmospheric Sciences Oceanography Geomatic Engineering Meteorology & Atmospheric Sciences |
description |
The interdecadal Pacific oscillation (hereafter termed IPV, using "variability" in lieu of "oscillation") and the Atlantic multidecadal oscillation (hereafter AMV, similar to IPV) are regulators of global mean temperature, large-scale atmospheric circulation, regional temperature and precipitation, and related extreme events. Despite a growing recognition of their importance, the combined influence of these modes of lowfrequency sea surface temperature (SST) variability remains elusive given the short instrumental record and the difficulty of coupled climate models to simulate them satisfactorily. In this study, idealized simulations with two atmospheric global climate models (AGCMs) are used to show a partial cancellation of the North Pacific atmospheric response to positive IPV (i.e., deeper Aleutian low) by the concurrent positive phase of the AMV. This effect arises from a modulation of the interbasin Walker circulation that weakens deep convection in the western Pacific and the associated Rossby wave train into the northern extratropics. The weaker Aleutian low response is associated with less upward wave activity flux in the North Pacific; however, the associated stratospheric jet weakening is similar to when the +IPV alone forces the vortex, as additional upward wave activity flux over Siberia makes up the difference. While comparable warming of the polar stratosphere is found when the positiveAMVis included with the positive IPV, the downward propagation of the stratospheric response is significantly reduced, which has implications for the associated surface temperature extremes. The robust anticorrelation between the positive IPV and positive AMV signals over the North Pacific and their lack of additivity highlight the need to consider the IPV-AMV interplay for anticipating decadal changes in mean climate and extreme events in the Northern Hemisphere. |
format |
Article in Journal/Newspaper |
author |
Elsbury, D Peings, Y Saint-Martin, D Douville, H Magnusdottir, G |
author_facet |
Elsbury, D Peings, Y Saint-Martin, D Douville, H Magnusdottir, G |
author_sort |
Elsbury, D |
title |
The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter |
title_short |
The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter |
title_full |
The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter |
title_fullStr |
The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter |
title_full_unstemmed |
The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter |
title_sort |
atmospheric response to positive ipv, positive amv, and their combination in boreal winter |
publisher |
eScholarship, University of California |
publishDate |
2019 |
url |
https://escholarship.org/uc/item/7c98r35b |
op_coverage |
4193 - 4213 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
aleutian low Siberia |
genre_facet |
aleutian low Siberia |
op_source |
Journal of Climate, vol 32, iss 14 |
op_relation |
qt7c98r35b https://escholarship.org/uc/item/7c98r35b |
op_rights |
CC-BY |
op_rightsnorm |
CC-BY |
_version_ |
1766266095850749952 |