利用1951-2008年海口降水量资料和北半球500 hPa高度及相关环流特征指数资料,北太平洋海温及相关NINO区海温特征指数资料,分析了海口秋汛期(9-10月)旱涝的气候特征及其与500 hPa高度场、北太平洋海温场和相关特征指数的关系.结果发现:海口秋汛期(9-10月)降水年际变化大,旱涝年代际变化特征明显;北半球副高及太平洋各副高单体和东亚槽强度与位置异常变化以及西藏高原高度场异常变化,是影响海口秋汛期降水的主要因子;前期冬季12月和1月太平洋各副高单体位置变化和前期冬、春季各月份北半球极涡面积、东亚槽位置及西藏高原高度场异常变化,对海口秋汛期旱涝具有较好的指示性;前期11-2月赤道东太平洋海温距平分布型和11月关键区海温高低变化,也对海口秋汛期旱涝预测具有较好的指示意义.%Based on the precipitation data in Haikou, 500 hPa geopotential height over the North Hemisphere, index of related circulation characteristics, sea surface temperature(SST) of the North Pacific and associated SST NINO index during 1951-2008, the relationship among them were analyzed in drought and flood seasons during the autumn flood season (September to October) in Haikou. The results showed that there was no obvious inter-annual variation of rainfall but obvious inter-decadal variation between drought and flood decades in Haikou during autumn flood season. The abnormal changes of intensity and locations of the Northern Hemisphere subtropical high, the Pacific subtropical high monomers and the East Asian trough, as well as the anomalies of the height field over the Tibetan plateau are the major factors affecting the precipitation in Haikou during the autumn flood season. The changes in the position of the Pacific subtropical high monomers in early winter (December and January), monthly anomalies of the polar vortex area over the northern hemisphere, the location of the East Asian trough and the height field over the Tibetan plateau during the early winter and spring are indicators for drought and flood in autumn flood seasons of Haikou. The anomalous SST spatial distribution at the eastern equatorial Pacific in earlier November to February and the magnitude of SST changes in the key areas in November are good indicators in predicting droughts and floods in Haikou during autumn flood season.
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