金塔绿洲不同下垫面辐射特征对比分析  

ANALYSIS OF CHARACTERISTICS OF RADIATION ON DIFFERENT UNDERLYING SURFZCE IN JINTA OASIS

作　　者：陈世强[1] 文莉娟[1] 吕世华[1] 奥银焕[1] 张宇[1] 

机构地区：[1]中科院寒区旱区环境与工程研究所,兰州730000

出　　处：《太阳能学报》2006年第7期713-718,共6页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金重点项目(40233035)

摘　　要：利用2005年在甘肃省金塔绿洲开展的“绿洲系统能量与水分循环过程观测试验”所取得的资料，系统的分析了夏季晴天金塔地区不同下垫面的辐射收支特征，结果表明：地表反照率呈“U”型分布，戈壁的最大，日平均为0．23，依次为沙漠点0．2、绿洲点0．19、临近沙漠的绿洲点0．18。4个观测站的太阳总辐射基本相近，在观测期内未出现超太阳常数的现象。向下和反射的短波辐射具有相同的日变化规律。4站大气逆辐射全天约在300～400Wlrn2之间。绿洲的地面向上的长波辐射强度小，日变化也不明显，白天略大于夜间；戈壁和沙漠的向上长波辐射强度较大，日变化较明显，其峰值远大于绿洲和临近沙漠的绿洲上的。绿州地表放射的净长波辐射与短波吸收辐射之比分别为25％和33％，远小于沙漠和戈壁地区的比值57％、60％，仅为沙漠和戈壁地区的比值的50％左右。在辐射平衡中地表长波贡献最大，大气逆辐射次之，总辐射第三，净辐射第四，反射辐射最小。绿洲上的净辐射可达总辐射的一半以上，而戈壁和沙漠上则仅略大于30％。The characteristics of radiation budget on different underlying surface were discussed by using the data got from ＂The Oasis System Energy and Water Cycle Field Experiment＂ in Jinta Oasis of Gansu Provience. Results were showed that the diurnal albedo distributed according to the shape of U. For albedo of the four observed stations, the largest was Gebi, next desert, the smallest was the oasis near the desert. The solar radiation trends and values of different stations were close and there was no over solar constant case in the experimental period. The diurnal variations of downward and upward short wave radiation were same. Downward longwave radiation of four stations had the range of 300 - 400W/m^2. Upward longwave irradiance of two oasis stations had small and the diurnal variation was not obvious. The value in the night was smaller than in the day. Upward longwave irradiance on Gebi and Desert were much larger than on Oasis. Their diurnal variation was very obvious. The ratio of valid longwave radiation to absorbed shortwave radiation on oasis which were 25% and 33%, respectively, was only half of the value on Gebi and Desert which were 57% and 60%, respectively. In the balance of radiation budget, the largest was the upward longwave radiation, the second was downward longwave radiation, the third was solar radiation , the fourth was the net radiation, and the smallest was upward shortwave radiation.The ratio of the net radiation to the solar radiation on oasis was more than 50% ,but on Gebi and Desert the value was only more than 30%.

关 键 词：辐射收支 金塔绿洲 沙漠 戈壁 

分 类 号：TK511[动力工程及工程热物理—热能工程]