摘要
用EOF和SVD方法分析了Climatic Research Unit的1951—2005年全球逐月海温距平场的时空变化特征及其与中国160个测站的月降水距平的时滞和空间耦合关系,讨论全球海温距平场的空间分布和时间演变对我国降水异常的影响,并着重分析了关键区在其特定关键时段内对我国降水异常的影响区域。结果表明,全球海温距平场有三个影响我国降水的关键区,即北太平洋、印度洋和我国南海以及赤道中东太平洋。这三个关键区的海温距平场具有明显的年际和年代际变化特征,突变发生在1976年左右,对我国降水有较为显著的影响,其中北太平洋关键区前期冬季海温对我国7月降水的影响、印度洋及南海前期冬春海温对我国5月降水的影响以及赤道中东太平洋前期冬季海温对我国7月降水的影响显得尤为重要。讨论了这三个关键区前期的海温距平场对我国不同区域不同时期降水影响的耦合关系,为我国区域降水异常预测的不确定性提供了依据。
The spatial and temporal coupling relationships between the monthly global SST anomaly field from 1951 to 2005 offered by Climatic Research Unit and the average monthly precipitation anomaly offered by 160 stations in China are analyzed. The spatial and temporal characteristics are analyzed with the EOF and SVD methods. After that, the influences of the spatial distribution and temporal evolution of global SST anomaly field on China＇s precipitation anomaly are analyzed, with the emphasis on the key areas which influence the precipitation anomaly in China in particular periods of time. The results show that there are three key regions which have important influence on the precipitation of China, namely, North Pacific, Indian Ocean-South China Sea and Middle and East equatorial Pacific. Having both interannual and interdecadal variations, the SST anomaly fields of the three key regions changed suddenly in the late 1970s. There are three key areas in these fields whose preceding wintertime SST has important influences on the precipitation in China： The first key area is over North Pacific, which affects the precipitation of July, the second one is over the Indian Ocean and South China Sea, which affects the precipitation of May, and the third one is over the Middle and East Equatorial Pacific, which affects the precipitation of July. In the last part of out study, the coupling relationships between the previous SST anomaly field of each key region and the precipitation field in different periods and different regions of China are analyzed. It may help reduce the uncertainty in the prediction of the abnormality of regional rainfall in China.
出处
《热带气象学报》
CSCD
北大核心
2009年第5期561-570,共10页
Journal of Tropical Meteorology
基金
国家自然科学基金面上项目(40675042)
"国家重点基础研究发展计划"项目(2004CB418300)共同资助
关键词
气候变化
EOF和SVD分解
降水距平
全球海温异常
climate change
EOF and SVD methods
anomaly of precipitation in China
anomaly of global sea temperature
