中文摘要：

利用青藏高原北部五道梁地区实测的太阳辐射及气象资料,计算分析了高原北部地面热量平衡方程中各分量特征,定义了一个无量纲参量土壤热平衡系数k。结果显示：五道梁地区地表净辐射及地面加热场强度表现为夏季大,冬季小,地表净辐射累年平均通量为65.5 W/m2;土壤热通量自1997年来有增大的趋势;土壤热平衡系数有增大的趋势,平均值为1.17;感热及潜热是地面热平衡方程中的大项,其中感热居首位,潜热居其次;暖季感热、潜热以相反的趋势变化,Bowen比β值有下降的趋势。

英文摘要：

The energy budget is an important domain in the research of the Earth-air＇s physical processes on the Tibetan Plateau.In order to have a good understanding of the surface energy regime,the characteristics of each component in the equation of the surface heat balance are analyzed by using the data observed on radiation,surface and air temperature and moisture pressure from Sep.1993 to Dec.2000 at Wudaoliang in the northern Tibetan Plateau.And for analyzing the soil heat condition,one dimensionless quantity,the soil heat balance coefficient（K） is defined.The results show that the surface net radiation and surface heating fields are big in summer and small in winter,the mean value of surface net radiation is about 65.5 W/m2.There is good relationship between the net radiation and the surface heating field.As for the soil heat conditions,there is an increasing trend for soil heating flux and K from 1997.And during the 7 years observation there are six years in which K values are bigger than 1.0, which means heat amount absorbed by soil is bigger than that emitted by the soil and the frozen ground will be degenerate.For the sensible heat and latent heat,the variation trend in the warmer season is different between the ratio H/Rn and LE/Rn.The ratios H/Rn are among the range from 0.628 to 0.741,which is the dominant component of the surface heat balance equation.And Bowen ratio decreases from 1994 to 2000.