日出后对流边界层的发展和上坡风的侵蚀使逆温和冷湖不断被破坏，最终消失。

After sunrise the convective boundary layer begins to grow up with upslope wind to develop in CBL.

研究结果表明：（1）北京区域夏季边界层风场受西北特殊地形的影响，夜间低层大气流场常表现为由北向南的下坡风，白天逐渐转为由南往北的上坡风。

Such results are gotten:(1) Due to the unique topography the wind of Beijing area during the day time is southern anabatic wind and in the night is northern katabatic wind in summer.

研究结果表明：（1）北京区域夏季边界层风场受西北特殊地形的影响，夜间低层大气流场常表现为由北向南的下坡风，白天逐渐转为由南往北的上坡风。

Such results are gotten: (1) Due to the unique topography the wind of Beijing area during the day time is southern anabatic wind and in the night is northern katabatic wind in summer.