DOI: | 10.1175/JCLI-D-13-00353.1
|
Scopus记录号: | 2-s2.0-84901823759
|
论文题名: | Changes in cyclone characteristics in response to modified SSTs |
作者: | Graff L.S.; Lacasce J.H.
|
刊名: | Journal of Climate
|
ISSN: | 8948755
|
出版年: | 2014
|
卷: | 27, 期:11 | 起始页码: | 4273
|
结束页码: | 4295
|
语种: | 英语
|
Scopus关键词: | Vortex flow
; Vorticity
; Atmospheric general circulation models
; Extratropical cyclones
; Impact of changes
; Lagrangian tracking
; Potential vorticity gradients
; Relative vorticity
; Sea surface temperature (SST)
; Southern Hemisphere
; Storms
; advection
; algorithm
; atmospheric general circulation model
; cyclone
; extratropical environment
; potential vorticity
; sea surface temperature
; Southern Hemisphere
; storm track
; temperature gradient
|
英文摘要: | The impact of changes in sea surface temperature (SST) on the statistics of extratropical cyclones is investigated. The cyclones were identified in an atmospheric general circulation model (AGCM) using an objective Lagrangian tracking algorithm, applied to the 850-hPa relative vorticity. The statistics were generated for several 20-yr simulations, in which the SSTs were warmed or cooled by 2Kin latitudinal bands. The response was studied in both hemispheres, during summer and winter. Changes in the position of the storm tracks are largely consistent with those seen in previous studies. Increasing SSTs uniformly or increasing the midlatitude SST gradient results in a poleward shift in the storm tracks, with the clearest trends seen in the Southern Hemisphere (SH). Here it is demonstrated that the SST modifications alter the cyclone characteristics as well. When the warming includes the low latitudes and/or the midlatitude gradient is increased, there are more short-lived cyclones. These are also on average more intense and translate faster, both poleward and eastward. The poleward displacement is correlated with cyclone intensity, so that stronger cyclones translate to higher latitudes. This is suggestive of vortex self-advection in the presence of a mean potential vorticity (PV) gradient. The increased eastward translation is correlated with the depth-averaged zonal velocity, and so is likely related to an increase in the steering-level velocity. These changes in cyclone translation probably contribute to the changes in the storm tracks seen previously. © 2014 American Meteorological Society. |
Citation statistics: |
|
资源类型: | 期刊论文
|
标识符: | http://119.78.100.158/handle/2HF3EXSE/51022
|
Appears in Collections: | 气候变化事实与影响
|
There are no files associated with this item.
|
作者单位: | Meteorology and Oceanography Section, Department of Geosciences, University of Oslo, P.O. Box 1022, Blindern, N-0315 Oslo, Norway
|
Recommended Citation: |
Graff L.S.,Lacasce J.H.. Changes in cyclone characteristics in response to modified SSTs[J]. Journal of Climate,2014-01-01,27(11)
|
|
|