The wet-dry changes in recent 40 years in taklimakan area.

Using the precipitation data in recent 40 years of 48 meteorological stations in Taklimakan area and neighboring areas, this paper analyzes the stage and periodicity of the wet-dry changes in a year and four seasons. The paper also compares the correlativity of precipitation between Taklimakan area and around Mountains, and obtained some statistic conclusions as follows. (1) The precipitation changes of a year and four seasons in Taklimakan area have different wet-dry periods and change periodicities. (2) Summer precipitation has well directive sense to annual precipitation in Taklimakan area with a correlation coefficient 0.901, and the negative correlation between precipitation and temperature in summer is very remarkable. (3) There is definite correlation between annual precipitation in Taklimakan area and position of polar vortex. When longitude of polar vortex is partial west in February and its latitude is partial north in September of the last year, annual precipitation is above its mean in the area. In addition, it is beneficial to obtain more summer precipitation in the area when position of polar vortex is partial west in February. [ABSTRACT FROM AUTHOR]