【摘要】 运用相关分析和滑动相关方法,分析了江淮流域5个代表站1903-2000年梅雨期雨量的变化特征及其与太平洋海温的相关关系及年代际差异.结果表明,江淮地区梅雨期雨量在近百年来存在明显的年际和年代际变化特征.通过分析梅雨期雨量与太平洋海温的年代际相关特征发现,江淮流域梅雨期雨量与前期及同期太平洋海温关系密切,前一年冬季及梅雨期东北太平洋海温与江淮流域梅雨期雨量负相关,在热带东太平洋的Nino1+2区两者正相关显著,同年春季西太平洋部分海域海温与江淮流域梅雨期雨量正相关.从年际相关分析发现,前一年冬季太平洋海温与梅雨期雨量正相关,同年春季以及梅雨期两者相关不明显.通过分析年代际差异发现,江淮流域梅雨期雨量与前期及同期热带太平洋关键区海温的21a滑动相关存在显著的年代际差异,这种差异与海温的21a滑动平均的年代际冷暖背景关系密切,热带太平洋海温关键区前一年冬季冷海温背景下,梅雨期雨量同海温正相关显著,同年春季暖海温背景下,两者之间负相关显著,而江淮流域梅雨期雨量同中国近海海温之间(从冬季到梅雨期)维持显著的正相关,与该区海温冷暖背景的关系则并不明显.更多还原

【Abstract】 Correlation and moving correlation analysis are used in this paper in order to find out the relation between the total precipitation in the Yangtze-Huaihe River valley during Meiyu period (Meiyu precipitation) and the sea surface temperature (SST) in the Pacific Ocean from the previous winter to Meiyu period. The results indicate that there exist obvious interannual and interdecadal variations of Meiyu precipitation from 1903 to 2000, and a decreased trend during the last 100-year period. In the previous winter and Meiyu period, the interdecadal correlation coefficients between Meiyu precipitation and SST of the northeast Pacific Ocean are negative, and in the Nino 1+2 area, the coefficients are positive. From previous winter to Meiyu period, the interdecadal correlation coefficients between Meiyu precipitation and SST of Mexico Gulf are always negative. In the Pacific Ocean, the interannual correlation coefficients between SST of the previous winter and Meiyu precipitation are positive, and this is helpful for short-term climate prediction. On the contrary, the correlation coefficients are very small and incredible between Meiyu precipitation and SST of the previous spring and Meiyu period. The 21a moving average and moving correlation analysis of Meiyu precipitation and SST indicate that from the previous winter to Meiyu period, the moving correlation coefficients between Meiyu precipitation and SST of Pacific Ocean change with the different background of SST. When SST background in the tropical Pacific Ocean is cold in the previous winter, the moving coefficients are positive, which means that under the condition of cold ocean, previous winter SST increases, Meiyu precipitation will also increase. In the previous spring, if there is no abnormity about the background of tropical Pacific Ocean SST, the moving coefficients are negative, and if SST is higher, then Meiyu precipitation will be much less. In Nino 1+2 area and Nino 3 area, when there is positive abnormity of SST background during Meiyu period, the high SST leads to plenteous Meiyu precipitation, while the abnormity is negative, the high SST leads to less Meiyu precipitation. The relationship between Meiyu precipitation and SST over the China Sea is changeless during the last 100 years, and the 21a moving correlation coefficients are independent on the SST background.更多还原