Characteristics And Numerical Simulation Of The Phenomenon Of Lake-Land Breeze In Bosten Lake Area

Bosten Lake,one of the largest inland freshwater lakes in China,is located in the southern foot of the central Tianshan Mountains.The diurnal variation and seasonal characteristics of the lake/land breeze from June 2013 to May 2014 were analyzed using the suaface observation.Based on mesoscale numerical simulation,the development of lake/land breeze of Bosten Lake and its interaction with the mountain/valley breeze of Tianshan Mountains are explored.In addition,two set of triple experiments which include with lake and without lake experiment were conducted to analyze the significant impact of Bosten Lake on the atmospheric boundary layer structure and local circulation.The results show that local circulation enhancement caused by the coupling of the lake breeze in the north of the Bosten Lake and the valley breeze in the south of the central Tianshan Mountains.From the shore to the mountain,the maximum of the local wind has a variation of increase,decrease and then increase.The onset of lake breeze does not show a significant delay in the near shore area,and when the offshore distance is greater than 20 km,the onset of the lake breeze is delayed by 1 h every 6 km.The lake breeze fronts in the north of the Bosten Lake can move much more distance than in the south,where without the influence of big mountain.As the lake breeze fronts in the north of the Bosten Lake approached the mountain,the coupling of the lake breeze and the valley breeze strengthened.Bosten lake makes the atmospheric boundary layer height over the lake lower than the land when the lake breeze is strongest.The regular patterns are the opposite when the land breeze is strongest.It is found that the lake-breeze circulation is the main component of local circulation.After removing the lake,the convergence,divergence,and vertical movement of the original lake area will be reduced.