新安江水库流域降水时间演变特征

Temporal Variation Characteristics of Precipitation in Xin'anjiang Reservoir Basin

为了解新安江水库流域降水的长期演变特征,利用2006~2022年GPM降水数据、GLDAS土壤含水率数据和典型站点的降水量与水位数据,结合HYSPLIT、PSCF、CWT模式,分析了降水量和水位的时间演变特征、不同降水气团的差异和降水的潜在来源。结果表明,干流单一站点的降水量可用于代表新安江水库流域的降水量变化特征。降水量、0~200 cm土壤含水率和水位存在明显月际变化,降水量在6月最高,土壤含水率和水位在7月最高。2006~2022年新安江流域的降水气团共分为六类:1型西南内陆远距离气团(31.8%)、2型西北内陆气团(7.2%)、3型局地气团(19.7%)、4型西南内陆近距离气团(15.7%)、5型东部海洋气团(3.8%)和6型西部内陆气团(21.8%)。不同类型气团降水的时间分布特征存在显著差异。新安江流域降水的PSCF分布与CWT分布类似,高值区均位于其西南方向。新安江流域的降水潜在来源贡献主要是江西全省和湖南省的东部地区,在对其降水过程预报时应多关注该区域的降水气团变化。研究结果可为新安江水库防汛和水力发电提供理论依据。

To understand the long-term evolution characteristics of precipitation in the Xin'anjiang Reservoir Basin,using the GPM precipitation data,GLDAS soil water content data,and precipitation and water levels data from 2006 to 2022,based on the HYSPLIT model,PSCF model and CWT model,the temporal variation characteristics of precipitation and water levels,the difference of different precipitation air masses and the potential sources of precipitation were analyzed.The results show that the precipitation at a single station in the mainstream basin can represent the precipitation variation characteristics of the entire watershed.Significant monthly variations existed in precipitation,0-200 cm soil moisture content and water level,with the highest precipitation in June and the highest soil moisture content and water level in July.The precipitation air masses in the Xin'anjiang Basin from 2006 to 2022 were divided into six types:Type 1 southwest inland long-distance air mass(31.8%),type 2 northwest inland air mass(7.2%),type 3 local air mass(19.7%),type 4 southwest inland close air mass(15.7%),type 5 eastern ocean air mass(3.8%)and type 6 western inland air mass(21.8%).Significant differences exist in the temporal distribution characteristics of different types of air mass precipitation.The distribution of PSCF and CWT of precipitation in the Xin'anjiang Basin is similar,and the highvalue areas are located in the southwest direction.The precipitation contribution of the Xin'anjiang Basin mainly comes from Jiangxi and Eastern Hunan Province,and more attention should be paid to the changes in precipitation air masses in this region when forecasting the precipitation process.The research results can provide the theoretical basis for flood control and hydropower generation in the Xin'anjiang Basin.