Variation in wind regimes and drift potential in the Ulan Buh Desert from 1973 to 2020

Wind is the driving force of land desertification and the formation and evolution of aeolian sand landforms． This study analyzed the characteristics of changes in speed, frequency, direction of sand transport wind, and drift potential at three stations around the Ulan Buh Desert from 1973 to 2020． The results show that: 1) The sand transport wind speed in the Ulan Buh Desert shows significant spatial and seasonal differences． It is the highest in the southwest, the lowest in the southeast, and intermediate in the northeast． Seasonally, it is the highest in spring, followed by winter, and the lowest in summer and autumn． In the past 48 years, the mean annual sand transport wind speed and its frequency of occurrence have decreased at rates of 0.1 m·s⁻¹ and 0.2% per decade, respectively． 2) The dominant directions of sand transport winds in the southwest, northeast, and southeast are northerly winds, westerly winds, and southerly and westerly winds, respectively. Significant seasonal and interdecadal variations were also observed in the dominant wind direction in the past 48 years． The decadal changes in the dominant wind direction of sand transport winds in the southwest, northeast, and southeast of the desert are characterized by three trends: alternating dominance of northeast and northwest winds, alternating dominance of southwest and northwest winds, and a transition from southerly to westerly winds． 3) Drift potential of Ulan Buh Desert ranged from 57.3 to 129.6 VU, belonging to a low wind energy environment． The wind direction variability ranged from 0.31 to 0.68, indicating a moderate variability． In the past 48 years, the drift potential in the Ulan Buh Desert has decreased by 30%, with the rate of decrease being the highest in the northeast, middle in the southwest, and the lowest in the southeast． The research results will provide scientific basis for evaluating the intensity of wind and sand activity in Ulan Buh Desert, the evolution of aeolian sand landforms, and the rational allocation of wind and sand prevention measures．