A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys
Abstract. The leading mode of wintertime variability in Northern Hemisphere sea level pressure (SLP) is the Arctic Oscillation (AO). It is usually obtained using linear principal component analysis, which produces the optimal, although somewhat restrictive, linear approximation to the SLP data. Here...
Main Author: | |
---|---|
Other Authors: | |
Format: | Text |
Language: | English |
Published: |
2000
|
Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.475.7287 http://web.uvic.ca/~monahana/cccma.nlpca.pdf |
id |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.475.7287 |
---|---|
record_format |
openpolar |
spelling |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.475.7287 2023-05-15T14:57:20+02:00 A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys A. H. Monahan The Pennsylvania State University CiteSeerX Archives 2000 application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.475.7287 http://web.uvic.ca/~monahana/cccma.nlpca.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.475.7287 http://web.uvic.ca/~monahana/cccma.nlpca.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://web.uvic.ca/~monahana/cccma.nlpca.pdf text 2000 ftciteseerx 2016-01-08T07:34:30Z Abstract. The leading mode of wintertime variability in Northern Hemisphere sea level pressure (SLP) is the Arctic Oscillation (AO). It is usually obtained using linear principal component analysis, which produces the optimal, although somewhat restrictive, linear approximation to the SLP data. Here we use a recently introduced nonlinear principal com-ponent analysis to nd the optimal nonlinear approxima-tion to SLP data produced by a 1001 year integration of the CCCma coupled general circulation model (CGCM1). This approximation’s associated time series is strongly bimodal and partitions the data into two distinct regimes. The rst and more persistent regime describes a standing oscillation whose signature in the mid-troposphere is alternating am-pli cation and attenuation of the climatological ridge over Northern Europe, with associated decreasing and increasing daily variance over Northern Eurasia. The second and more episodic regime describes a split-flow south of Greenland with much enhanced daily variance in the Arctic. In a 500 year integration with atmospheric CO2 stabilized at concen-trations projected for year 2100, the occupation statistics of these preferred modes of variability change, such that the episodic split-flow regime occurs less frequently while the standing oscillation regime occurs more frequently. 1. Text Arctic Global warming Greenland Unknown Arctic Greenland |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
ftciteseerx |
language |
English |
description |
Abstract. The leading mode of wintertime variability in Northern Hemisphere sea level pressure (SLP) is the Arctic Oscillation (AO). It is usually obtained using linear principal component analysis, which produces the optimal, although somewhat restrictive, linear approximation to the SLP data. Here we use a recently introduced nonlinear principal com-ponent analysis to nd the optimal nonlinear approxima-tion to SLP data produced by a 1001 year integration of the CCCma coupled general circulation model (CGCM1). This approximation’s associated time series is strongly bimodal and partitions the data into two distinct regimes. The rst and more persistent regime describes a standing oscillation whose signature in the mid-troposphere is alternating am-pli cation and attenuation of the climatological ridge over Northern Europe, with associated decreasing and increasing daily variance over Northern Eurasia. The second and more episodic regime describes a split-flow south of Greenland with much enhanced daily variance in the Arctic. In a 500 year integration with atmospheric CO2 stabilized at concen-trations projected for year 2100, the occupation statistics of these preferred modes of variability change, such that the episodic split-flow regime occurs less frequently while the standing oscillation regime occurs more frequently. 1. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
A. H. Monahan |
spellingShingle |
A. H. Monahan A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys |
author_facet |
A. H. Monahan |
author_sort |
A. H. Monahan |
title |
A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys |
title_short |
A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys |
title_full |
A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys |
title_fullStr |
A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys |
title_full_unstemmed |
A regime view of northern hemisphere atmospheric variability and change under global warming, Geophys |
title_sort |
regime view of northern hemisphere atmospheric variability and change under global warming, geophys |
publishDate |
2000 |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.475.7287 http://web.uvic.ca/~monahana/cccma.nlpca.pdf |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic Global warming Greenland |
genre_facet |
Arctic Global warming Greenland |
op_source |
http://web.uvic.ca/~monahana/cccma.nlpca.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.475.7287 http://web.uvic.ca/~monahana/cccma.nlpca.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766329410832564224 |