Midsummer Low-Level Circulation and Precipitation in Subtropical South America and Related Sea Surface Temperature Anomalies in the South Atlantic
Midsummer Low-Level Circulation and Precipitation in Subtropical South America and Related Sea Surface Temperature Anomalies in the South Atlantic
复制标题
南美洲副热带仲夏低层环流和降水及相关的南大西洋海温异常
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
V. Barros
中科院分区：
文献类型：
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作者：
M. Doyle;V. Barros
摘要利用再分析资料、区域降水资料和月海温资料，研究了与西副热带南大西洋（WSSA）海表温度（SST）异常相关的副热带南美洲（SA）低层对流层环流和降水场的盛夏年际变率。利用典型相关分析确定了西太平洋海温与亚热带南澳大利亚州降水关系最密切的区域。这一区域的范围为南纬20°至30°，西经30°至50°。对应于该地区极端海温的合成图在低层环流和降水场中表现出两种分化较好的型。在合成图中，对应于该地区海温正距平偏高，来自大陆低纬的低空气流和水汽输送的主流在10°S处开始向东南方向移动，并在35°S处与西向气流在大西洋上空汇合。在T...
Abstract The midsummer interannual variability of the low-level tropospheric circulation and of the precipitation field in subtropical South America (SA) associated to the sea surface temperature (SST) anomalies in the western subtropical South Atlantic Ocean (WSSA) is investigated using reanalyses, regional precipitation datasets, and monthly SSTs. The region of the WSSA where SST has the strongest relation with precipitation in subtropical SA was identified using canonical correlation analysis. This region extends from 20° to 30°S and from 30° to 50°W. Composites corresponding to extreme SSTs in this area show two well-differentiated patterns in the low-level circulation and in the precipitation fields. In the composite, corresponding to the more positive SST anomalies in this area, the mainstream of the low-level flow and of the moisture transport from the continental low latitudes starts to follow a southeastward direction at 10°S, and converges with the west flow at 35°S over the Atlantic Ocean. On t...