CHARACTERISTICS OF SURFACE WINDS IN TAKLA-MAKAN DESERTS AND THEIR RELATIONSHIP TO THE ORIENTATION OF DUNES IN NEIGHBORING REGIONS

Study is performed of the near-surface wind fields in the Takla-Makan Deserts by use of 17-station winds and the high-level circulation situation, with focus on the relation between wind-filed features and dunes arranged in the neighboring areas. Results suggest that in the background of upper-air westerlies, the near-surface wind features are produced from the dynamic bifurcation and lifting by Tibetan Plateau and Tianshan Mountain Ranges, as shown in the following: in winter easterly (westerly) winds prevail east (west) of the Niya River; in summer northwesterly and westerly (northeasterly) winds are prevalent west (east) of the Keriya River; the NE (NW) winds get decreased (increased) form east to west, with N—S wind strength changing in a complex manner; the sand transport potential is less than 200 VU in the Takla-Makan Deserts except Ruoqiang County, the Deserts falling into a low-energy wind environment dominated by a single-peak or an acute bi-peak form, with the energy higher in the eastern and middle parts and low in the western and southern portions of the Deserts; the orientation of dunes depends largely on the concluded angle between the major and minor winds for carrying sands and the ratio of their transported sands, with the orientation perpendicular to the maximum sand amount transferred.