Cargando…

The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors

Tropospheric features preceding sudden stratospheric warming events (SSWs) are identified using a large compendium of events obtained from a chemistry–climate model. In agreement with recent observational studies, it is found that approximately one-third of SSWs are preceded by extreme episodes of w...

Descripción completa

Detalles Bibliográficos
Autores principales: WHITE, IAN, GARFINKEL, CHAIM I., GERBER, EDWIN P., JUCKER, MARTIN, AQUILA, VALENTINA, OMAN, LUKE D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7440399/
https://www.ncbi.nlm.nih.gov/pubmed/32831474
http://dx.doi.org/10.1175/JCLI-D-18-0053.1
_version_ 1783573157876072448
author WHITE, IAN
GARFINKEL, CHAIM I.
GERBER, EDWIN P.
JUCKER, MARTIN
AQUILA, VALENTINA
OMAN, LUKE D.
author_facet WHITE, IAN
GARFINKEL, CHAIM I.
GERBER, EDWIN P.
JUCKER, MARTIN
AQUILA, VALENTINA
OMAN, LUKE D.
author_sort WHITE, IAN
collection PubMed
description Tropospheric features preceding sudden stratospheric warming events (SSWs) are identified using a large compendium of events obtained from a chemistry–climate model. In agreement with recent observational studies, it is found that approximately one-third of SSWs are preceded by extreme episodes of wave activity in the lower troposphere. The relationship becomes stronger in the lower stratosphere, where ~60% of SSWs are preceded by extreme wave activity at 100 hPa. Additional analysis characterizes events that do or do not appear to subsequently impact the troposphere, referred to as downward and non-downward propagating SSWs, respectively. On average, tropospheric wave activity is larger preceding downward-propagating SSWs compared to non-downward propagating events, and associated in particular with a doubly strengthened Siberian high. Of the SSWs that were preceded by extreme lower-tropospheric wave activity, ~2/3 propagated down to the troposphere, and hence the presence of extreme lower-tropospheric wave activity can only be used probabilistically to predict a slight increase or decrease at the onset, of the likelihood of tropospheric impacts to follow. However, a large number of downward and non-downward propagating SSWs must be considered (>35), before the difference becomes statistically significant. The precursors are also robust upon comparison with composites consisting of randomly selected tropospheric northern annular mode (NAM) events. The downward influence and precursors to split and displacement events are also examined. It is found that anomalous upward wave-1 fluxes precede both cases. Splits exhibit a near instantaneous, barotropic response in the stratosphere and troposphere, while displacements have a stronger long-term influence.
format Online
Article
Text
id pubmed-7440399
institution National Center for Biotechnology Information
language English
publishDate 2018
record_format MEDLINE/PubMed
spelling pubmed-74403992020-08-20 The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors WHITE, IAN GARFINKEL, CHAIM I. GERBER, EDWIN P. JUCKER, MARTIN AQUILA, VALENTINA OMAN, LUKE D. J Clim Article Tropospheric features preceding sudden stratospheric warming events (SSWs) are identified using a large compendium of events obtained from a chemistry–climate model. In agreement with recent observational studies, it is found that approximately one-third of SSWs are preceded by extreme episodes of wave activity in the lower troposphere. The relationship becomes stronger in the lower stratosphere, where ~60% of SSWs are preceded by extreme wave activity at 100 hPa. Additional analysis characterizes events that do or do not appear to subsequently impact the troposphere, referred to as downward and non-downward propagating SSWs, respectively. On average, tropospheric wave activity is larger preceding downward-propagating SSWs compared to non-downward propagating events, and associated in particular with a doubly strengthened Siberian high. Of the SSWs that were preceded by extreme lower-tropospheric wave activity, ~2/3 propagated down to the troposphere, and hence the presence of extreme lower-tropospheric wave activity can only be used probabilistically to predict a slight increase or decrease at the onset, of the likelihood of tropospheric impacts to follow. However, a large number of downward and non-downward propagating SSWs must be considered (>35), before the difference becomes statistically significant. The precursors are also robust upon comparison with composites consisting of randomly selected tropospheric northern annular mode (NAM) events. The downward influence and precursors to split and displacement events are also examined. It is found that anomalous upward wave-1 fluxes precede both cases. Splits exhibit a near instantaneous, barotropic response in the stratosphere and troposphere, while displacements have a stronger long-term influence. 2018-12-05 2019-01-01 /pmc/articles/PMC7440399/ /pubmed/32831474 http://dx.doi.org/10.1175/JCLI-D-18-0053.1 Text en http://creativecommons.org/licenses/by/4.0/ Denotes content that is immediately available upon publication as open access.
spellingShingle Article
WHITE, IAN
GARFINKEL, CHAIM I.
GERBER, EDWIN P.
JUCKER, MARTIN
AQUILA, VALENTINA
OMAN, LUKE D.
The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors
title The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors
title_full The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors
title_fullStr The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors
title_full_unstemmed The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors
title_short The Downward Influence of Sudden Stratospheric Warmings: Association with Tropospheric Precursors
title_sort downward influence of sudden stratospheric warmings: association with tropospheric precursors
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7440399/
https://www.ncbi.nlm.nih.gov/pubmed/32831474
http://dx.doi.org/10.1175/JCLI-D-18-0053.1
work_keys_str_mv AT whiteian thedownwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT garfinkelchaimi thedownwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT gerberedwinp thedownwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT juckermartin thedownwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT aquilavalentina thedownwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT omanluked thedownwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT whiteian downwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT garfinkelchaimi downwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT gerberedwinp downwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT juckermartin downwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT aquilavalentina downwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors
AT omanluked downwardinfluenceofsuddenstratosphericwarmingsassociationwithtroposphericprecursors