Basic Characteristics of Meteorological Elements and Observed Local Wind Circulation in Taklimakan Desert, China.

摘要

Desert in Xin-jiang, China, since 1991 to investigate the desertification processes of arid lands. For this purpose, an automatic weather station was installed over gobi desert at the southern edge of the Taklimakan Desert. Observed data for about one year were analyzed and compared with the data over grass on the outskirts of the oasis. The monthly mean of soil surface temperature is higher than that of air temperature in every month. This means that the monthly mean sensible heat flux is upward all the year round. Daytime increase of specific humidity is evident in the summer season and is probably caused by the water vapor advection from the relatively wet oasis area located upwind. Two prevailing wind directions were found : a strong (&ge ; 7.0 ms-1) westerly wind from April to June, and a southsoutheasterly wind during nighttime. The southsoutheasterly wind is accompanied by the diurnal clockwise wind course which is found throughout the year. Diurnal variations of wind direction at gobi and grass within oasis, 11 km away from gobi, show same characteristics. An identical wind course can be recognized in the vertical profile at Hotan, 100 km west of the gobi site, from the surface to 160 m in height. It is strongly suggested that this diurnal wind course is induced by the local circulation between Kunlun Mountains and the desert area.