DOI: 10.1175/JCLI-D-14-00482.1
Scopus记录号: 2-s2.0-84920265480
论文题名: A climatology of cold air outbreaks and their impact on air-sea heat fluxes in the high-latitude South Pacific
作者: Papritz L. ; Pfahl S. ; Sodemann H. ; Wernli H.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2015
卷: 28, 期: 1 起始页码: 342
结束页码: 364
语种: 英语
Scopus关键词: Climatology
; Ice
; Sea ice
; Storms
; Cold air
; Downslope winds
; Extratropical cyclones
; Mesocyclones
; Southern ocean
; Surface flux
; Heat flux
; air-sea interaction
; climatology
; cold air
; evaporation
; heat flux
; storm track
; surface flux
; tropical cyclone
; Amundsen Sea
; Bellingshausen Sea
; Pacific Ocean
; Pacific Ocean (South)
; Ross Sea
; Southern Ocean
英文摘要: A climatology of cold air outbreaks (CAOs) in the high latitudes of the South Pacific and an analysis of the dynamical mechanisms leading to their formation are presented. Two major and distinct regions with frequent CAOs from autumn to spring are identified: one in the Ross Sea and another in the Amundsen and Bellingshausen Seas. Using an objective method to attribute CAOs to extratropical cyclones, it is shown that about 80% of the CAOs occur in association with the cyclonic flow induced by the passage of extratropical cyclones. Based on kinematic backward trajectories it is quantified that more than 40% of the air masses leading to CAOs originate from Antarctica and descend substantially, with the Ross Ice Shelf corridor as the major pathway. CAO trajectories descending from Antarctica differ from those originating over sea ice by a much lower specific humidity, stronger diabatic cooling, and much more intense adiabatic warming, while potential vorticity evolves similarly in both categories. In winter, CAOs are the major contributor to the net turbulent heat flux off the sea ice edge and CAO frequency strongly determines its interannual variation. Wintertime variations of the frequency of extratropical cyclones are strongly imprinted on the frequency of CAOs and the net turbulent heat and freshwater fluxes. In particular, much of the precipitation associated with the passage of extratropical cyclones is compensated by intense evaporation in cyclone-induced CAOs. This highlights the dominant role of the extratropical storm track in determining the variability of the buoyancy flux forcing of the Southern Ocean. © 2015 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/50515
Appears in Collections: 气候变化事实与影响
There are no files associated with this item.
作者单位: Institute for Atmospheric and Climate Science, Center for Climate Systems Modeling, ETH Zürich, Zurich, Switzerland; Institute for Atmospheric and Climate Science, ETH Zürich, Zurich, Switzerland
Recommended Citation:
Papritz L.,Pfahl S.,Sodemann H.,et al. A climatology of cold air outbreaks and their impact on air-sea heat fluxes in the high-latitude South Pacific[J]. Journal of Climate,2015-01-01,28(1)