Impacts of Underlying Surface on the Dusty Weather in Central Inner Mongolian Steppe, China

Abstract

AbstractDust storms are common in northern China and can adversely affect the environment and human health. The Xilingol grassland is the main source of dust storms in China. However, the impacts of different surface features on dusty weather in the Xilingol League remain unclear. This study analyzed the temporal and spatial variation characteristics of surface features and the corresponding effects on dusty weather using data from 13 meteorological stations, MODIS normalized difference vegetation index (NDVI) data, and soil moisture data collected in Xilingol League from 2005 to 2018. Spatially, the dust outbreak frequency (DOF) of Xilingol League decreased gradually from the western desert steppe to the eastern typical steppe. Temporally, the dust outbreak ratio (DOR) and DOF were highest in spring (March–May), with the highest in April. Dusty weather mostly occur in spring but gradually decreased in this season over the 14‐year period. On the contrary, NDVI and soil moisture increased gradually from the west with less precipitation to the east with more precipitation. And showed fluctuating increasing trends over time. The DOR in Xilingol League was negatively correlated with the NDVI and soil moisture, and with the increase of NDVI and soil moisture from the western desert steppe to the eastern typical steppe and the southern cultivated land, the dust emission threshold also increased. The DOR predicted by Xilingol league in spring was significantly correlated with the actual DOR. Our research can provide specific suggestions for different regions of Xilingol League.