黑河中上游不同下垫面反照率特征及其影响因子分析  

Albedo Characteristics in Different Underlying Surfaces in Midand Upper-Reaches of HEIFE and Its Impact Factor Analysis

作　　者：孙俊[1,2] 胡泽勇[1] 荀学义[1] 彭雯[1] 吕斌[2] 徐丽娇[1] 

机构地区：[1]中国科学院寒旱区陆面过程与气候变化重点实验室,中国科学院寒区旱区环境与工程研究所,甘肃兰州730000 [2]四川省遂宁市气象局,四川遂宁629000

出　　处：《高原气象》2011年第3期607-613,共7页Plateau Meteorology

基　　金：中国科学院西部行动计划(二期)项目(KZCX2-XB2-09-04);国家自然科学基金项目(40875005,40633014);欧盟第七框架项目(FP7-ENV-2007-1Grantnr.212921)共同资助

摘　　要：利用黑河中上游6个自动气象站2008年6月-2009年5月的观测资料,分析了该地区6种典型下垫面反照率变化特征和太阳高度角对反照率的影响,针对垭口站和花寨子站分别讨论了积雪和土壤湿度对反照率的影响。结果表明,不同季节太阳高度角对反照率的影响不同,不同的下垫面影响的程度也不一样。在积雪下垫面,太阳高度角对反照率的影响最大,其次为森林;在牧草和农田站,夏季植被生长旺盛季,太阳高度角对反照率的影响要比冬季的大。观测资料分析表明,表层土壤湿度对反照率的影响非常显著,零星小雨虽然不能渗透到地表以下,但仍会引起表层土壤湿度增加,导致反照率出现短时明显降低。不同的降雨量对反照率的影响也不同。根据年平均反照率得出各种下垫面反照率的相对关系为高寒草甸>荒漠>牧草>农田>稀疏草地>森林。Using the observed data at six automatic stations in the mid-and upper-reaches of HEIFE from June 2008 to May 2009,the seasonal variations of albedo on different underlying surfaces are analyzed.The influences of solar elevation angle,soil moisture,and precipitation on albedo are also studied in this paper.The impact of snow cover on the albedo at Yakou station is discussed.Meanwhile,the soil moisture data are also related to albedo to discuss its influence at Huazhaizi station.The results show that the solar elevation angle in different seasons has different effect on albedo,while its impact is also different on different underlying surfaces.Solar elevation angle on snow surface has the greatest impact on alebdo,and the second is the forest land cover.At herbage and farmland stations,the solar elevation angle has greater impact on albedo in summer than that in winter.By analyzing the observed data,the surface soil moisture has a significant impact on albedo.Although sporadic rain can not infiltrate into the ground,it can still cause albedo decrease in a short time because of increasing the surface soil moisture.The different intensity of precipitation has different effect on albedo.According to the average annual albedo,the sequence of albedo at six stations are alpine meadow〉desert〉herbage〉farmland〉thin grass〉forest,respectivily.

关 键 词：黑河中上游 反照率 太阳高度角 积雪 土壤湿度 

分 类 号：P422.9[天文地球—大气科学及气象学]