郑州地区城市化对一次暴雨过程影响的模拟研究  

Impact of Urbanization on a Torrential Rain Process in Zhengzhou Region

作　　者：董俊玲[1,2] 刘超 苏爱芳[1,2] DONG Junling;LIU Chao;SU Aifang(Henan Key Laboratory of Agrometeorological Support and Applied Technique,CMA,Zhengzhou 450003,China;Henan Provincial Meteorological Observatory,Zhengzhou 450003,China)

机构地区：[1]中国气象局河南省农业气象保障与应用技术重点开放实验室,河南郑州450003 [2]河南省气象台,河南郑州450003

出　　处：《干旱气象》2019年第6期922-932,共11页Journal of Arid Meteorology

基　　金：中国气象局气象预报业务关键技术发展专项《发展多源观测资料快速融合分析技术与强对流天气短时临近预警关键技术》(YBGJXM(2018)02);中国气象局预报员专项《2017年河南极端短时强降水特征及机制分析》(CMAYBY2018-045);山东省气象科学研究所数值天气预报应用技术开放研究基金《WRF模式中不同陆面方案和陆面资料对强降水预报的影响》(SDQXKF2015M09)共同资助

摘　　要：近年来郑州地区城市化迅速发展,为分析郑州地区城市下垫面扩张对天气过程,特别是暴雨过程的影响,本文利用城市冠层模式(UCM)与WRF3.7模式耦合对2017年5月22日的暴雨过程进行模拟研究。通过改变模式下垫面,设计3组敏感性试验,分别是原始USGS下垫面(方案1),郑州市内5区改为城市(方案2),郑州市行政区范围内都改成城市(方案3)。结果表明,WRF模式能够较好地模拟出这次暴雨的时空分布特征,总体上城市下垫面扩张增强了此次暴雨过程在郑州地区的降水,但对降水的影响分布不均,对城市中心及其上风方向的巩义、荥阳地区的影响更为明显。郑州地区城市化使得城市区域感热通量增加,边界层高度升高,垂直速度增强,有利于城市边界层大气中不稳定能量的积聚,有助于强降水的发生发展。同时,城市下垫面扩张使得城区水汽蒸发减少,潜热通量降低,影响水汽通量的分布,部分地区的水汽条件变差,不利于降水的发生发展。In recent years,the urbanization in Zhengzhou region developed rapidly.In order to analyze the impact of urban underlying surface expansion on the weather process,especially torrential rain process,the coupled WRF3.7/UCM model was used to simulate the torrential rain process occurring on 22 May 2017,and the impact of Zhengzhou urbanization on this process was analyzed.Based on the changing of underlying surface,3 sensitivity tests were set:original USGS land cover data(scheme 1),land cover data changing the 5 districts in downtown of Zhengzhou into urban(scheme 2),land cover data changing all Zhengzhou city into urban(scheme 3).The results indicated that the WRF3.7/UCM model could represent the temporal and spatial distribution characteristics of this torrential rain process quite well.With the effect of urbanization,the total precipitation in Zhengzhou region increased,while the effect was different in different areas,which was more significant in the center and upwind of Zhengzhou.On one hand,urbanization caused the increasing of sensible heat flux,boundary layer height and vertical velocity,which promoted the accumulation of unstable energy,and contributed to the occurrence and development of heavy rainfall.On the other hand,urbanization caused the decreasing of water evaporation and latent heat flux,and changed the distribution of water vapor flux.The water vapor condition became unfavorable to the occurrence and development of rainfall in some areas.

关 键 词：郑州 城市化 暴雨 WRF模拟 

分 类 号：P461[天文地球—大气科学及气象学]