干旱半干旱区不同下垫面边界层特征分析  

Analysis of boundary layer characteristics over different underlying surfaces in arid and semi-arid regions

作　　者：赵艳茹[1] 张京朋 郭燕玲[1] 马翼宁 吴宪初 马永敬 张文煜[1] 

机构地区：[1]兰州大学大气科学学院,甘肃省干旱气候变化与减灾重点实验室,兰州730000

出　　处：《兰州大学学报（自然科学版）》2015年第4期539-545,552,共8页Journal of Lanzhou University(Natural Sciences)

基　　金：国家重点基础研究发展计划(973计划)(2012CB956200);国家自然科学基金项目(41225018)

摘　　要：选取干旱半干旱区具有不同下垫面特征的黄土高原和河西走廊代表站点2006-2013年的探空资料,对其边界层高度、边界层内的位温、比湿、风速等特征量在不同时间、不同高度的变化特点进行了比较分析,结果表明07:15两地区边界层高度多在300～600 m,且黄土高原地区要高于河西走廊地区;19:15两地区边界层高度多在200～500 m左右,且河西走廊地区要高于黄土高原地区.两地区边界层高度的变化均呈现出一定的周期性,在每年4、5月份左右达到峰值.黄土高原地区位温及其随高度递增率整体大于河西走廊地区;黄土高原地区比湿整体大于河西走廊地区;河西走廊地区风速廓线随高度变化差异大于黄土高原地区.各特征参数随着高度的增加,差异逐渐减小,说明下垫面对边界层特征的影响在近地层表现得尤为明显.The sounding data from 2006 to 2013 of arid and semi-arid areas with different underlying surfaces of the Loess Plateau and Hexi Corridor were selected to analyze the changing characteristics of the boundary layer height, potential temperature, specific humidity and wind speed within the boundary layer at different times and different height changes and results showed that in the morning, the boundary layer height of Hexi Corridor and Loess Plateau were at 300~600 m, witht the latter being higher than the former; in the evening the boundary layer height of Hexi Corridor and Loess Plateau were at 200~500 m, with the former being higher than the latter. Both the boundary layer heights of the two regions presented certain annual cycles, and peaks around April and May every year. The Loess Plateau＇s potential temperature was greater than Hexi Corridor on the whole, and the height increasing rate of the Loess Plateau was greater than Hexi Corridor; the Loess Plateau＇s specific humidity was greater than Hexi Corridor on the whole; the difference of the wind speed profile in Hexi Corridor was greater than that in the Loess Plateau. Difference in the kinds of characteristic parameters gradually decreased with the increase of height, and this explains that the influence of underlying surface on the boundary layer characteristics is especially apparent in the surface layer.

关 键 词：干旱半干旱区 不同下垫面 边界层高度 特征参数变化 

分 类 号：P433[天文地球—大气科学及气象学]