淮河流域汛期暴雨与西太平洋海温关系

The Relationship Between Flood Season Rainstorm in the Huaihe River Basin and West Pacific Sea Surface Temperature

利用淮河流域172测站1960—2009年逐日气象资料和全球海温资料,通过对淮河流域汛期暴雨与前期西太平洋海温的相关分析来研究海温的变化对淮河流域汛期暴雨的影响。选取西太平洋海域（158°～170°E,8°～14°N）作为关键海区,前一年5—6月作为关键时段,通过分析发现海温偏低（高）年,淮河流域的绝大部分地区的暴雨量减少（增加）,淮河流域东北部呈现与其他地区反相的变化特征;在暴雨偏多（少）年,对应的前一年5—6月关键海区正好是海温偏高（低）。正是由于西太平洋关键海区持续的海温异常引起了次年汛期大气环流的异常,导致了淮河流域汛期暴雨的异常,这正是海温与暴雨具有很好相关的内在原因。

Through the correlation analysis between the flood season rainstorm in Huaihe River basin and the West Pacific sea surface temperature, the effects of West Pacific sea surface temperature on the flood season rainstorm in the Huaihe River basin are studied using the daily rain data from 172 stations in the Huaihe River basin and NOAA OERSST data from 1960 to 2009. The Western Pacific（158°～170°E,8°～14°N）is chosen as the key area and May-June of last year are chosen as the key period. It is found that rainstorm in most Huaihe River Basin area is reduced（increased） in lower（higher） SST year. What is noteworthy is that a reverse change occurs between the variation features of the northeast part and the other parts. In the rich（poor）rainfall years the temperature of the key sea area in May-June of the last year is higher than normal. It is the circulate anomalies in the following flood season induced by the key area SSTA distribution pattern over the West Pacific that result in the flood season rainstorm anomaly in the Huaihe basin.It is also the inner cause of the good correlation between the flood season rainstorm and the SSTA.