Temporal and spatial variation of atmospheric water vapor in the Taklimakan Desert and its surrounding areas

The study of the temporal and spatial variation of atmospheric water vapor has the important significance to show the response to climate change in the Taklimakan Desert. The series of monthly atmospheric water vapor from 1961 to 1998 are reconstructed using the observation data including the precipitation, ground water vapor pressure data over the period of 1961 to 2006 from 27 observation stations in its surrounding areas and meteorological data from the Tazhong station during 1999–2006. Then the relationship between atmospheric water vapor and ground vapor pressure is calculated and validated using the observation data for the period of 1976 to 2006 from 5 sounding stations (Hotan, Kuqa, Ruoqiang, Kashgar, and Minfeng). The temporal and spatial variation of atmospheric water vapor in the Taklimakan Desert and its surrounding areas is studied and then its distribution is generated. Results show that high value zone of atmospheric water vapor is mainly distributed in the northern Taklimakan Desert and the oasis-marginal belt of western desert and the value ranges from 14 to 15 mm. The low value center of atmospheric water vapor is in the hinterland of the desert and the value is only 7–8 mm. The annual variations of atmospheric water vapor show generally the increasing trend. However, the variation of atmospheric water vapor in the surrounding areas and the hinterland of the desert is insignificant during 1961–1986. The atmospheric water vapor changes abruptly after 1986 and increases clearly in the two regions. The variation trend accords with that of the precipitation’s increasing significantly in southern Xinjiang for the recent 50 years. There is great error between the NCEP/NCAR reanalysis data of atmospheric water vapor and real data in the Taklimakan Desert.