抚河流域降水序列趋势和突变特征分析

采用一元线性回归分析、累积距平、Spearman秩次相关系数和Mann-Kendall方法对抚河流域1979-2008年春季、夏季、秋季、冬季以及年均降水序列特征和趋势进行分析,应用Mann-Kendall突变分析法分析其时间序列突变点。结果表明:(1)抚河流域降水年内主要集中于3-6月份,10-12月份较少;年际变化上,降水较多年份主要集中在20世纪90年代后期,降水较少的年份主要集中在本世纪初,尤其是2003年前后。(2)抚河流域春季、夏季和年均降水均存在减少趋势,在冬季存在增加趋势,但趋势并不显著,在秋季基本无趋势变化。(3)抚河流域四季和年均降水大致经历增加-减少-增加-减少4个阶段。(4)春季降水序列突变点为1992年和1995年;夏季降水序列突变点为1986年、1997年和2007年;秋季降水序列存在1997年一个突变点;冬季降水序列突变点发生在1988年和1991年;年均降水序列突变时间分别发生在1985年、1998年和2005年。就整体来说,抚河流域降水突变时间发生在20世纪80年代后期和90年代后期。

The precipitation characteristics of Fuhe basin based on Mann-Kendall method

In this paper, we analyzed the characteristics and trend of the precipitation in Fuhe basin from 1979 to 2008 using linear regression analysis, cumulative anomalies, spearman rank correlation coefficient and Mann-Kendall methods. We also analyzed the abrupt change adopting Mann-Kendall method. The results showed that: 1) The precipitation during the year was concentrated in March, April, May and June, and it was less in October, November and December. In the annual change, the precipitation was concentrated in the 1990s, and was less in the turn of this century, especially around 2003. 2) The precipitation decreased in spring, summer and average year among the time series, and it increased in winter, but the trend was not significant. In fall, the precipitation was relatively stable, and there was almost no change. 3) The precipitation generally experienced four phases in the time series: increasing - decreasing - increasing - decreasing. 4) The abrupt changes of spring series were in 1992 and 1995, and in summer, they were in 1986, 1997 and 2007. There was only one break in fall, which was in 1997, and in winter, the abrupt changes were in 1988 and 1991. In the annual year, the abrupt changes were in 1985, 1998 and 2005. In the whole, the precipitation abrupt change happened in the late 1980s and the late 1990s.