DOI: 10.1175/JCLI-D-12-00351.1
Scopus记录号: 2-s2.0-84880656856
论文题名: An objective climatology of tropical plumes
作者: Fröhlich L. ; Knippertz P. ; Fink A.H. ; Hohberger E.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2013
卷: 26, 期: 14 起始页码: 5044
结束页码: 5060
语种: 英语
Scopus关键词: Eastern north pacific
; Interannual variation
; Length-to-width ratio
; ROSSBY wave propagation
; South atlantic convergence zones
; Tropical disturbances
; Tropical-extratropical interactions
; Upper-level trough
; Algorithms
; Climatology
; Geographical distribution
; Tropics
; air-sea interaction
; atmospheric plume
; brightness temperature
; El Nino
; geographical distribution
; monsoon
; Rossby wave
; seasonal variation
; threshold
; wave propagation
; Atlantic Ocean
; Atlantic Ocean (North)
; Atlantic Ocean (South)
; Pacific Ocean
; Pacific Ocean (North)
; Pacific Ocean (South)
英文摘要: The first global objective climatology of tropical plumes (TPs), obtained from a novel algorithm based on gridded 10.8-μmbrightness temperatures Tb, is presented for 1983-2006. TPs are defined as continuous cloud bands (>2000 km) crossing 15°Nor 15°S with Tb anomalies of less than220 K and a lifetime of at least 3 h. A minimum length-to-width ratio of 3 filters out elongated features. Numbers of identified TPs are sensitive to the chosen thresholds but not their geographical distribution and seasonal cycle. TPs are an important indicator of tropical-extratropical interactions with impacts on radiation and moisture. TP occurrence during boreal winter is largely confined to oceanic regions with main maxima over the South Pacific and South Atlantic as well as the eastern North Atlantic and Pacific Oceans. The geographical distribution during boreal summer is similar, but with lower frequencies, except for monsoon-influenced regions. Interannual variations over the Indo-Pacific region are strongly related to El Niño. TPs often develop downstream of extratropical upper-level troughs propagating into low latitudes, particularly over the wintertime eastern North Pacific and North Atlantic, but also in regions where mean upper-level easterlies do not generally favor equatorward Rossby wave propagation. Synoptic-scale variations in the quasi-permanent cloud bands associated with the South Pacific and South Atlantic convergence zones frequently produce TP-like anomalies, which are climatologically associated with downstream upper-level troughs. Some regions also feature TPs associated with mesoscale tropical disturbances. The new TP algorithm will serve as a basis for more in-depth studies in the future. ©2013 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/51765
Appears in Collections: 气候变化事实与影响
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作者单位: Institute of Geophysics and Meteorology, University of Cologne, Cologne, Germany; School of Earth and Environment, University of Leeds, Leeds, United Kingdom; Institute of Flight Systems and Automatic Control, Technical University Darmstadt, Darmstadt, Germany
Recommended Citation:
Fröhlich L.,Knippertz P.,Fink A.H.,et al. An objective climatology of tropical plumes[J]. Journal of Climate,2013-01-01,26(14)