Wind erosion events at different wind speed levels in the Tarim Basin

Abstract Wind is a dynamic force in deserts and is responsible for wind erosion when its speed exceeds a given threshold velocity (ut). This study classified these wind speeds (≥ ut) at intervals of 1 m/s and aimed to determine the characteristics of wind erosion events (horizontal dust flux and duration of the wind erosion event) at different wind speed levels (WSLs) based on continuously measured meteorological data recorded from 2009 to 2018 at 12 meteorological stations. In addition, their relationships with the WSL were analyzed in the Tarim Basin. The results indicated that 82.57% of the total wind erosion events occurred at WSL 1 and 2 (ut to ut + 2 m/s). As the WSL increased, the duration of wind erosion events decreased rapidly. More than 50% of the total horizontal dust flux presented at WSL 2 and 3 (ut + 1 m/s to ut + 3 m/s), and all stations showed a maximum value at WSL 2 except RQ, which was at WSL 3. We also found that at WSL 1, the contribution of duration to the total amount was much greater than that of the horizontal dust flux, and it was basically consistent at WSL 2. With the increase in WSL, the contribution of duration to the total amount became gradually smaller than that of the horizontal dust flux. Furthermore, according to the spatial distribution, the high incidence of wind erosion events occurred in the southeast and central of TB at each WSL. Moreover, the regression model that best described the relationship between the WSL and the characteristics of wind erosion events was an exponential function (T = A × e-BVL and F = C × e-DVL, respectively). The results obtained from this study could provide a new insight for the evaluation of wind erosion in arid and semi-arid areas.