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

Abstracts: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: ①There are significant spatial and seasonal differences in sand transport wind speed of the Ulan Buh Desert which is that sand transport wind speed and average frequency of sand transport wind was highest in the southwest, while that is lowest in the northeast, and that wind speed of sand transport was highest in spring, followed by summer, and lowest in autumn and winter. In the past 48 years, the average sand transport wind speed, and average frequency of sand transport wind have decreased by 0.1 m·s⁻¹, and 0.2% per decade, respectively. ②The dominant direction of sand transport winds in the southwest, northeast, and southeast are northerly winds (NW, WNW, and NE), westerly winds (WSW and WNW), and southerly and westerly winds (SSE, SE, and WNW), respectively. There are significant regional and seasonal differences in the dominant wind direction of sand transport winds. There are interdecadal and seasonal differences in the dominant wind direction of sand transport winds 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. ③Drift potential of Ulan Buh Desert ranged from 57.3-129.6VU, belonging to a low wind energy environment. The wind direction variability ranges 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 highest in the northeast, middle in the southwest, and 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.