Abstract: The Xilingol region is one of the main typical steppes in China, it is located in an ecological fragile zone, and it is also an important ecological barrier around Beijing. In this paper, the correlations between sandstorm occurrence and climatic factors were analyzed, and the rating matrix of meteorological factors was used to calculate the composite scores so as to research the risk of meteorological factors resulting in sandstorm disasters. The result revealed that the frequency percentage of sandstorm occurred in spring was 77.28%, and the seasonal characteristics of occurring frequency of sandstorm were obvious. Moreover, the occurring frequency of sandstorm was in a decreasing trend in recent 30 years. Spatially, the occurring frequency of sandstorm was gradually decreased from the west to the east, and the areas with high occurring frequency were the desert steppes and the farmingpastoral ecotones. Formation and development of sandstorm are closely related to climatic factors, but the effects of climatic factors on sandstorm occurrence are temporally different. Holistically, the risk of climatic factors resulting in sandstorm disasters in the southwestern and northeastern parts of the study area was higher than that in the central part, and the risk distribution of climatic factors accorded basically with the occurring frequency of sandstorm.

Key words: sandstorm, spatiotemporal distribution, climatic factor, risk assessment, desert steppe, farming pastoral ecotone, Xilingol region, Inner Mongolia