云南高原异龙湖冬季典型日湖面风场特征及其形成机制OA

The wind field over the lake surface plays a crucial role in driving lake flows and influencing the trans-port of pollutants within the lake.The inaccurate boundary condition for the lake surface wind is an important reason affecting the reliability of hydrodynamic and water quality models of lakes.The current understanding of the charac-teristics and the formation mechanism of the wind field over plateau lakes is still insufficient,which in turn affects our understanding of lake flows and imposes constraints on the governance and protection of plateau lake ecological systems.This study takes the Yilong Lake,one of the nine major plateau lakes in Yunnan,as a representative.It employs the mesoscale meteorological model WRF_CLM to simulate the local climatic characteristics of the Yilong Lake basin on a typical winter day and discusses the characteristics and formation mechanisms of the lake surface wind field.The results indicate that the wind field within the Yilong Lake basin during the study period is influ-enced by a combination of upper-level background winds,lake-land breezes,surrounding topography,and the urban heat island near the lake;Thermal dynamics play an indispensable role in the formation of the wind field over the lake surface;There is a distinct lake-land breeze in the basin,with lake breezes occurring between 11:00 and 16:00 and land breezes between 18:00 and 10:00 the following day.The area influenced by lake breezes typically spans around the lake within the range less than 100～300 meters above the lake surface.During the lake breeze pe-riod,the upper-level background wind generally has a marked impact on the land surface wind field,but its effect on the lake surface wind field is limited.During the land breeze period,the influences on both the land and lake surface wind fields are not significant.Additionally,tall mountains in the wind direction and nearby hills also play a role in shaping the lake surface wind field.The lake surface wind field exhibits notable spatial heterogeneity,which suggests that measurements of wind speed and direction from single or few points around the lake or on its sur-face are insufficient to accurately represent the true wind field over the lake.