赣江流域1966-2015年降水量多尺度时空变化特征分析

Spatiotemporal Variation Characteristics of Precipitation at Multi-scale in Ganjiang River Basin from 1966 to 2015

为研究全球气候变化影响下的赣江流域降水量时空分布特征,基于赣江流域及其周边的27个气象站1966-2015年逐日降水量数据,采用Mann-kendall、累积距平法及Morlet小波分析等方法研究了不同时间尺度降水量变化特征。结果表明:赣江流域年、汛期、夏季和秋季降水量呈不显著的增加趋势(p>0.05),而春季和冬季呈不显著的减少趋势(p>0.05);不同时间尺度降水量均具有明显的阶段性特征,且进入21世纪00年代后降水量多为枯水阶段;赣江流域降水量变化主周期多在8~10 a,20~22 a,26~30 a。赣江流域全年和春季降水量呈南少北多的分布格局,汛期和夏季降水量空间分布较均匀,无明显的空间差异,秋季降水量呈南北两端少、中部相对较多的分布格局,而冬季降水量呈由北向南递减的变化趋势。

In order to study the temporal and spatial distribution characteristics of precipitation in Ganjiang River Basin under the influence of global climate change,the spatiotemporal variation characteristics of precipitation in the Ganjiang River basin were investigated using mann-kendall,cumulative anomaly method and Morlet wavelet analysis based on the daily precipitation data of 27 meteorological stations within and around the basin.The results showed that the annual,flood season,summer and autumn precipitation in ganjiang river basin presented the insignificant increasing trend(p>0.05),and showed an insignificant decreasing trend in spring and winter(p>0.05);the precipitation of Ganjiang River Basin in different time scales had obvious stage characteristics,and the precipitation after the 2000′s was mostly in the dry stages;the main cycles of precipitation change in Ganjiang River Basin were usually 8~10 years,20~22 years,and 26~30 years;the annual and spring precipitation in Ganjiang River Basin was low in the southwest and high in the northeast;the distribution pattern of precipitation in autumn was high in the west and low in the east,while the change trend of precipitation in winter was decreasing from north to south;the distribution pattern of precipitation in flood and summer was uniform and had no distinct spatial difference.