2018年北京城区和远郊区低层大气风场特征分析  

Analysis of Wind Field Characteristics within the Lower Atmosphere in Urban and Suburban Areas of Beijing in 2018

作　　者：曹杨 何文英[4] 施红蓉 王普才[4] CAO Yang;HE Wenying;SHI Hongrong;WANG Pucai(Sichuan Meteorological Disaster Prevention Technology Center,Chengdu 610072;Key Laboratory of Atmospheric Chemistry,China Meteorological Administration,Beijing 100081;Key Laboratory of Atmospheric Sounding,China Meteorological Administration,Chengdu 610225;Key Laboratory of Middle Atmosphere and Global Environment Observation,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029)

机构地区：[1]四川省气象灾害防御技术中心,成都610072 [2]中国气象局大气化学重点开放实验室,北京100081 [3]中国气象局大气探测重点开放实验室,成都610225 [4]中国科学院大气物理研究所中层大气和全球环境探测重点实验室,北京100029

出　　处：《气候与环境研究》2021年第4期403-412,共10页Climatic and Environmental Research

基　　金：国家重点研发计划项目2017YFC1501700;国家自然科学基金项目41805021;中国气象局大气化学重点开放实验室开放项目2020B05。

摘　　要：利用2018年1月1日至12月31日在北京国家综合气象观测实验基地获得的风廓线雷达资料和同时期在河北香河的华北香河全大气层野外科学观测研究站获得的多普勒声雷达资料,比较分析北京城区和远郊区的低层(0~600 m)大气风场特征。结果表明:水平风速随高度增加而增大,同一高度层,远郊区的平均水平风速大于城区,且受湍流活动影响,城区和远郊区水平风速日变化趋势均为白天小于夜间。春、夏季城区风向受局地山谷风影响显著,以偏西南偏南气流为主,城区和远郊区秋冬季受冷空气活动影响,以西北风为主,且水平风向日变化特征具有季节性差异。远郊区低层大气垂直速度分布特征四季相同,正、负速度出现频率相当,日变化趋势为单峰型;城区冬春季有差异,在390 m高度以下正速度出现频率明显大于负速度,且日变化趋势在四季差异较大。北京城区和郊区风场特征差异与其他特大城市相比无特殊性,主要受大气环流、局地地形、下垫面环境等因素影响。Based on the Doppler sodar data observed at the Huabei Xianghe full atmosphere field scientific observation and research station and the wind profiler data obtained from the Beijing national comprehensive meteorological observation and test base during 1 January to 31 December 2018,this study compares and analyzes the wind field characteristics within the lower atmosphere in the urban and suburban areas of Beijing.Results show that in the aspect of the vertical structure,the horizontal wind speed increases gradually with height.At the same altitude,the average horizontal wind speed in the suburban area is more than that in the urban area,and the diurnal variation of the horizontal wind speed in the urban and suburban areas is smaller in the daytime than that in the nighttime.In spring and summer,the horizontal wind direction in the urban area is south-southwest,which is significantly affected by the valley-mountain breeze.The horizontal wind direction in the urban and suburban areas is northwest in autumn and winter,which is affected by the cold air activity.Additionally,the diurnal variation of horizontal wind direction changes seasonally.Vertical wind speed distribution characteristics of the lower atmosphere in the suburban area are the same in the four seasons,the frequencies of positive and negative speeds are similar,and the diurnal variation trend is single-peak.However,there are differences between winter and spring vertical wind speeds in the urban area.The frequency of positive speed below the altitude of 390 m is obviously greater than that of negative speed,and the diurnal variation trends are quite different in the four seasons.Compared with other megacities,the difference in wind field characteristics between urban and suburban areas of Beijing is not special,which is primarily affected by atmospheric circulation,local topography,and land surface environment.

关 键 词：声雷达 风廓线雷达 低层大气 风场特征 

分 类 号：P412.23[天文地球—大气科学及气象学]