我国西北典型干旱区和高原地区地表辐射能量收支特征的比较

The Comparison of Surface Radiation Budget between Typical Arid Region in Northwest China and Plateau Region

利用“中国西北干旱区陆气相互作用观测试验（NWC—LAIEX）”所获取一年的地面辐射观测资料（2000年5月-2001年4月），比较分析了我国典型干旱区敦煌戈壁、临泽沙漠和藏北高原五道梁地区地表辐射能量的收支特征。结果表明：3个地区各辐射分量季节变化明显，春季一般为跳跃式增加，而秋季则急剧减小，敦煌和临泽地区总辐射月总量几乎全年都小于藏北高原的五道梁地区，冬季最为明显。五道梁和临泽地区的地表反照率有较明显的季节变化和日变化，季节变化是夏季较小，冬季大；而敦煌戈壁地区的反照率不论是季节变化还是日变化，都比较平缓；3个地区相比，临泽沙漠地区的反照率最大，五道梁地区次之，敦煌戈壁地区最小。敦煌戈壁和临泽沙漠地区的地面向上长波辐射和大气逆辐射都比藏jE高原的五道梁地区大。地面有效辐射在敦煌戈壁和临泽沙漠地区是夏季大，冬季小；而在藏北高原的五道梁地区则是春秋季大，冬夏季小。地面有效辐射与地面吸收辐射之比敦煌戈壁和临泽沙漠地区量值相近，藏北高原的五道梁地区较小，夏季尤为突出。在夏季，五道梁的地表净辐射要远远大于其他两个地区，冬季3个地区量值相当。与地表净辐射相对应，五道梁地区的地面热源强度在夏季大于敦煌戈壁地区，在冬季相差不大。

Based on ＂NWC-LAIEX＂ （Field Experiment on Interaction between Land and Atmosphere over Arid Region in Northwest China） observation data over three different sites from May 2000 to April 2001, the surface radiation budget characteristics of typical underlying surfaces that are Gobi without vegetation cover in Dunhuang and desert with dotted grass in Linze and Gobi with some sparse grass in Wudaoliang of the Northern Tibetan Plateau are analyzed and compared. The results are as follows： the seasonal variations of aforementioned three different regions are quite obvious, in generally, which increase jumpily and decrease rapidly. The monthly grosses of total solar radiation of Gobi in Dunhuang and desert in Linze are less than that of Wudaoliang region almost during the whole year, especially in winter. The seasonal and diurnal variations of surface albedo of desert in Linze and Wudaoliang regions are obvious and greater than that of in Gobi of Dunhuang. The surface upward longwave radiations of Gobi and desert in Northwest China are larger than that of in Wudaoliang, but the seasonal variations in three sites are obvious. The net longwave radiations of Gobi in Dunhuang and desert in Linze are large in summer, and small in winter, hut it is reverse in Wudaoliang. The surface net radiations are much less over Gobi in Dunhuang and desert in Linze than in Wudaoliang in summer, hut almost same in winter. Corresponding to net radiation, the surface heating field is much larger in Wudaoliang than in Dunhuang Gobi region in summer, but almost no difference in winter.