The analysis of sea-land breeze and thermal inner boundary layer at Huludao

Based on routine weather station data of windward and wind speed in 2007,we analyzed sea-land breeze character at Huludao.Using MM5v3 model,we simulated wind field change character when sea-land breeze occur-ring and calculated the distance of sea wind extending into the land and land wind extending ton the sea.The appearance frequencies of sea breeze and land breeze were obvious of seasonly change.Land breeze happened in winter,sea breeze happened in summer and spring,and sea-land breeze happened in spring and autumn.The dura-tion of sea breaze was long in summer and short in winter;The duration of land breaze was longer in autumn and winter than in summer;In a characteristc sea-land breeze day,sea breeze greatly increase the humidity on land,and the speed of sea breeze was larger than the speed of land breeze.Via numerical value modeling of sea breeze,from initiation to matureness the thickness was about 2 000 m,the distance of extension into land was 40 km.The ther-mal inner boundary layer assumed a tongue-like figure,the thickness of thermal inner boundary layer was 200-300 m.The altitude of parabola was increased as the distance of land was increased.The highest altitude of thermal inner boundary layer was 1 800 meters.