DOI: 10.1007/s00382-015-2858-9
Scopus记录号: 2-s2.0-84944603541
论文题名: Weather types across the Caribbean basin and their relationship with rainfall and sea surface temperature
作者: Moron V. ; Gouirand I. ; Taylor M.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2016
卷: 47, 期: 2017-01-02 起始页码: 601
结束页码: 621
语种: 英语
英文关键词: Air–sea coupling
; Annual cycle
; ENSO
; Seasonal prediction
英文摘要: Eight weather types (WTs) are computed over 98.75°W–56.25°W, 8.75°N–31.25°N using cluster analysis of daily low-level (925 hPa) winds and outgoing longwave radiation, without removing the mean annual cycle, by a k-means algorithm from 1979 to 2013. The WTs can be firstly interpreted as snapshots of the annual cycle with a clear distinction between 5 “wintertime” and 3 “summertime” WTs, which account together for 70 % of the total mean annual rainfall across the studied domain. The wintertime WTs occur mostly from late November to late April and are characterized by varying intensity and location of the North Atlantic subtropical high (NASH) and transient synoptic troughs along the northern edge of the domain. Large-scale subsidence dominates the whole basin but rainfall can occur over sections of the basin, especially on the windward shores of the troughs associated with the synoptic waves. The transition between wintertime and summertime WTs is rather abrupt, especially in May. One summertime WT (WT 4) is prevalent in summer, and almost exclusive around late July. It is characterized by strong NASH, fast Caribbean low level jet and rainfall mostly concentrated over the Caribbean Islands, the Florida Peninsula, the whole Central America and the tropical Eastern Pacific. The two remaining summertime WTs display widespread rainfall respectively from Central America to Bermuda (WT 5) and over the Eastern Caribbean (WT 6). Both WTs combine reduced regional scale subsidence and weaker Caribbean low-level jet relatively to WT 4. The relationships between WT frequency and El Niño Southern Oscillation (ENSO) events are broadly linear. Warm central and eastern ENSO events are associated with more WT 4 (less WT 5–6) during boreal summer and autumn (0) while this relationship is reversed during boreal summer (+1) for central events only. In boreal winter, the largest anomalies are observed for two WTs consistent with negative (WT 2) and positive (WT 8) phases of the North Atlantic Oscillation; more (less) WT 2 and less (more) WT 8 than usually occur from January to early April during warm (cold) ENSO events, the strongest anomalies being recorded during eastern events. Multinomial logistic regression is used to hindcast the 11-day low-pass filtered occurrence of WTs from local (Caribbean Sea and Gulf of Mexico) and remote (Eastern and Central Tropical Pacific) sea surface temperatures (SSTs). In boreal summer, the interannual variability of the seasonal occurrence of WTs 4–6 is well hindcast when at least the Caribbean Sea and Eastern Tropical Pacific are included as predictors with anomalously warm (cold) SSTs over the Caribbean Sea (Eastern Tropical Pacific) being related to more WT 5–6 and less WT 4 and vice-versa. Using antecedent SST to forecast WT frequency shows that the SST forcing is negligible at the start of boreal summer and increases toward its end. © 2015, Springer-Verlag Berlin Heidelberg. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/53652
Appears in Collections: 过去全球变化的重建
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作者单位: Aix-Marseille University, CEREGE UM34 CNRS, Aix-en-Provence, France; IRI, Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; The University of the West-Indies, Cave Hill, Barbados; The University of the West-Indies, Mona Campus, Mona, Jamaica
Recommended Citation:
Moron V.,Gouirand I.,Taylor M.. Weather types across the Caribbean basin and their relationship with rainfall and sea surface temperature[J]. Climate Dynamics,2016-01-01,47(2017-01-02)