Historical Attribution and Future Projection of the Changes in Near-surface Wind Speed in China

The wind speed at 10 m (WS10) can significantly influence the natural environment and human society, but its changes and associated causes remain unclear. This study first evaluates the WS10 changes in various regions of China, based on station observations and a method involving the analysis of rotated empirical orthogonal function and hierarchical clustering. The results show that high WS10 is more likely to occur in the northwestern, eastern, and northern regions of China, where the WS10 has experienced rapidly decreasing trends in the recent decades. In contrast, lower values and smaller trends of WS10 are observed in the southern and central regions. Then, CMIP6 model simulations with historically all forcings and those with GHG-only, aerosol-only and natural-only forcings are analyzed to further evaluate the relative roles of human activity and natural variability in the WS10 changes over China, which show that the anthropogenic warming tends to induce a decreased WS10 in northern China. By comparisons between model simulations with land use and cover change (LUCC) and without LUCC, it is further revealed that the LUCC is more likely to affect the WS10 in eastern China than in western China. Finally, using CMIP6 models under different SSP scenarios, we assess the WS10 changes in China during the 21st century. In most areas of China, the CMIP6 models project a continuing decline of WS10 in all scenarios, with the larger decreases occurring in higher SSPs. This study improves our understanding of the causes of the past WS10 changes in China as well as their possible future changes, providing critical implications for wind energy development.