固液态降水分离方法探讨  

A Discuss of the Separating Solid and Liquid Precipitations

作　　者：韩春坛[1,2] 陈仁升[1,2] 刘俊峰[1,2] 阳勇[1,2] 卿文武[1,2] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所黑河上游生态-水文试验研究站,甘肃兰州730000 [2]中国科学院内陆河流域生态水文重点实验室,甘肃兰州730000

出　　处：《冰川冻土》2010年第2期249-256,共8页Journal of Glaciology and Geocryology

基　　金：中国科学院知识创新工程重要方向性项目(KZCX2-YW-301-3);国家自然科学基金项目(40771045;90702001-2);国家重点基础研究发展计划(973计划)项目(2007CB411506)资助

摘　　要：降雨径流和融雪径流在水文循环中是截然不同的,当前大多数水文模型采用临界气温法来分离降雨和降雪,但这个临界值是用户自定的,没有统一的临界值.根据1961-1979年全国643个基本和基准气象站日平均气温和降水数据(1980年以后数据库中未标记降水形态而无法应用)来统计降雨和降雪的临界气温值.选取单站降雨和降雪均为98.5%的保证率所对应的日平均气温值,作为固液降水分离的临界气温值,绘制我国范围的临界气温等值线图.同时,引进月降雪比率分离法,判断流域内某月是否有降雪,降雪量多少,但该方法易受站点分布的影响.两种方法可结合使用,后者可以作为前者的辅助.Rainfall-runoff and snow melting processes are much different in hydrology,thus the precipitation is categorized as solid and liquid in most hydrological models according to one or two air temperature thresholds which yet are user specified. Dot graphs are plotted to acquire the threshold by using daily mean air temperature and precipitation data at 643 stations from 1961 to 1979 （precipitation forms are not labeled from 1980 to date in the database） in China. However,because of the complexity of weather,the threshold is not so clear in the graphs,and that the two-temperature-threshold method is not practical in the most regions of China. Based on the rule ＂sacrifice minor things to save major ones＂,a temperature threshold is acquired when PP=98.5% at each station. Using the Gaussian-Kriging interpolation method,the isoline and contour surface maps of the threshold are drawn. The monthly snowfall ratio method is also imported,which can help judge whether the researched watershed has snowfall or not in a certain month,and how much the snowfall is. The two methods are recommended to use mutually,whereas the latter is only an assistant.

关 键 词：临界气温 降水形态 水文过程 寒区 概率 

分 类 号：P426.63[天文地球—大气科学及气象学]