Wind erosion has notable impacts on ecology, water supply and regional climate, but its distributions and longterm changes are still poorly quantified for the Tibetan Plateau (TP). This study develops a coupled land-surface wind-erosion model (HRLDAS-WEPS) in two dimensions horizontally to analyze wind-erosion distributions and its temporal variations under the climate change in 1979?2015 over the entire TP. Two model enhancements are also used, including the application of MODIS vegetation datasets and the optimization of snow-cover parameterizations. Evaluation results indicate that the enhanced coupled model can generally represent the winderosion distributions over the TP, being mainly located in the arid and semi-arid areas and occurring in winter and spring, as compared with station observations and satellite datasets. In 1979?2015, wind erosion has a significant (P < 0.01) decreasing trend of -0.54 kg m- 2 yr- 1 for annual total soil loss averaged over the arid and semi-arid areas of the TP, which is mainly due to the significant (P < 0.01) declining wind speed and increasing soil moisture. The severest wind-erosion reduction is located to the northwest of the 200 mm precipitation line and the Qaidam Basin. Furthermore, a significant turning point of wind-erosion variation is found in 1992. Specifically, wind erosion over the TP decreases from 1979 to 1991 (-1.26 kg m- 2 yr- 1), and then stays at a low level with a slight increase (0.08 kg m- 2 yr- 1) since 1993. This is probably due to the abrupt change of wind speed over the TP in 1991.
Wind erosion along the Qinghai-Tibet Railway causes sand hazard and poses threats to the safety of trains and passengers. A coupled land-surface erosion model (Noah-MPWE) was developed to simulate the wind erosion along the railway. Comparison with the data from the Cs-137 isotope analysis shows that this coupled model could simulate the mean erosion amount reasonably. The coupled model was then applied to eight sites along the railway to investigate the wind-erosion distribution and variations from 1979 to 2012. Factors affecting wind erosion spatially and temporally were assessed as well. Majority wind erosion occurs in the non-monsoon season from December to April of the next year except for the site located in desert. The region between Wudaoliang and Tanggula has higher wind erosion occurrences and soil lose amount because of higher frequency of strong wind and relatively lower soil moisture than other sites. Inter-annually, all sites present a significant decreasing trend of annual soil loss with an average rate of - 0.18 kg m(-2) a(-1) in 1979-2012. Decreased frequency of strong wind, increased precipitation and soil moisture contribute to the reduction of wind erosion in 1979-2012. Snow cover duration and vegetation coverage also have great impact on the occurrence of wind erosion.