小清河流域降水时空分布及变化特征分析

Analysis on Temporal and Spatial Distribution and Variation Characteristics of Precipitation in Xiaoqing River Basin

摘要:

基于小清河流域9处国家基本雨量站2006—2024年逐日降水数据,利用数理统计、降水集中度与集中期、累积距平法、小波分析等方法,探究流域降水的时空分布及变化特征。结果表明:流域年内降水分配呈现单峰型格局,主要集中于7—8月,年内变化剧烈;年际尺度上,降水总量保持稳定,下游极端性最强;降水集中度在2015年达历史最低后持续上升,显示降水年内分配由均匀化向集中化转变;流域降水在2018年前后经历由整体偏枯向偏丰的转折;预示流域降水量偏多的趋势可能持续至2029年前后。

Abstract:

Based on daily precipitation data from 9 national basic rainfall stations in the Xiaoqing River Basin during 2006—2024, it adopted the following methods such as mathematical statistics, precipitation concentration degree and concentration period, cumulative anomaly method, and wavelet analysis, to investigate the temporal and spatial distribution and variation characteristics of precipitation in the basin. The results show that the intra annual precipitation distribution presents a unimodal pattern, mainly concentrated in July and August with drastic intra annual variation. On the inter annual scale, total precipitation remains stable while the lower reaches witness the strongest precipitation extremity. The precipitation concentration degree reached its historical minimum in 2015 and has kept rising since then, indicating that intra annual precipitation distribution has shifted from homogenization to concentration. The basin experienced a transition from generally dry to flood around 2018, which suggests that the trend of above average precipitation may last until around 2029.