Changes of Frequency of Summer Precipitation Extremes over the Yangtze River in Association with Large-scale Oceanic-atmospheric Conditions |
| |
Authors: | WANG Yi YAN Zhongwei and |
| |
Institution: | National Meteorological Center, Beijing 100081, Key Laboratory of Regional Climate-Environment Research for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029,Key Laboratory of Regional Climate-Environment Research for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, |
| |
Abstract: | Changes of the frequency of precipitation extremes (the number of
days with daily precipitation exceeding the 90th percentile of a daily
climatology, referred to as R90N) in summer (June--August) over the mid-lower
reaches of the Yangtze River are analyzed based on daily observations during
1961--2007. The first singular value decomposition (SVD) mode of R90N is linked
to an ENSO-like mode of the sea surface temperature anomalies (SSTA) in the
previous winter. Responses of different grades of precipitation events to the
climatic mode are compared. It is notable that the frequency of summer
precipitation extremes is significantly related with the SSTA in the Pacific,
while those of light and moderate precipitation are not. It is suggested that
the previously well-recognized impact of ENSO on summer rainfall along the
Yangtze River is essentially due to a response in summer precipitation extremes
in the region, in association with the East Asia-Pacific (EAP) teleconnection
pattern. A negative relationship is found between the East Asian Summer Monsoon
(EASM) and precipitation extremes over the mid-lower reaches of the Yangtze
River. In contrast, light rainfall processes are independent from the SST and
EASM variations. |
| |
Keywords: | precipitation extremes ENSO East Asian Summer Monsoon the Yangtze River |
本文献已被 CNKI SpringerLink 等数据库收录! |
| 点击此处可从《大气科学进展》浏览原始摘要信息 |
| 点击此处可从《大气科学进展》下载免费的PDF全文 |
|