青藏高原东部土壤冻融过程中地表粗糙度的确定

Determination of Surface Roughness Length during Soil Freezing and Thawing Season over Eastern Qinghai-Xizang Plateau

利用黄河源区气候与环境综合观测研究站2006年10月—2007年4月的湍流观测资料和一种新的方法,计算了青藏高原东部玛曲地区土壤冻融过程中的地表粗糙度。结果表明:所用的计算粗糙度的方法是可行的,玛曲土壤未冻结阶段、冻结阶段和融化后阶段的地表粗糙度分别为3.23×10-3m,2.27×10-3m和1.92×10-3m,地表粗糙度呈逐渐减小的趋势。三阶段地表粗糙度有明显区别,以前将冬季前后的粗糙度取为定值的计算会导致一定的误差。

Using a new method and the turbulence observation data from Maqu station, the surface roughness length during soil freezing and thawing season over Eastern Qinghai-Xizang Plateau was estimated. The main results show that the method used in this paper is feasible to determine surface roughness length. Surface roughness length during soil freezing and thawing season has a little decrease trend. The surface roughness length of three phase in the season, unfrozen time, frozen time and melted time, are 3.23 10-3m, 2.27×10^-3mand 1.92×10^-3m, respectively. The contrast with other place shows that the surface roughness lengths in different places over Qinghai-Xizang Plateau have greater difference.