The Synoptic to Decadal Variability in the Winter Surface Wind Speed Over China by the Weather Regime View

The observed surface wind speed (SWS) has declined over the past 4 decades over China, which have has been examined from a climatological perspective. However, the SWS is highly variable and is dependent on the weather regime (WR). This study investigates the variability of winter SWS under six typical WRs and assesses the variability at the synoptic to decadal time scales. Our results reveal that the WRs impose important impacts on the spatial pattern and inter-annual variability of SWS over China. The Siberian high pressure exerts an important influence on the WR occurrence over Eastern Asia and affects the SWS variations, with more prominent impacts at the decadal time scale. The Aleutian low pressure exhibits weak inter-annual correlations with the SWS under all WRs but reveals closer decadal connections under certain WRs. However, WRs cannot sufficiently explain the decreasing trend of SWS from 1980 to 2017.

Automated summary

This study investigated the variability of surface wind speed in China under different weather regimes, highlighting the significant impacts of the Siberian high pressure and Aleutian low pressure on the wind speed, especially at decadal scales. However, these weather regimes cannot fully explain the decreasing trend of surface wind speed observed in China from 1980 to 2017.