LAPS上海本地化及其在局地对流天气中的应用研究

LAPS localization in Shanghai and its application in local convective weather

本文首先基于地面自动站、探空、雷达和卫星资料,开展局地分析预报系统(Local Analysis and Prediction System,LAPS)上海本地化研究,并结合2010—2014年夏季6个局地对流天气个例对其性能进行检验评估。结果表明:雷达径向风资料对LAPS风速分析影响较大,使分析场风速廓线与探空廓线的均方根误差缩小约7.66%;风云卫星资料能够改善LAPS温度和相对湿度,使分析场温度、相对湿度廓线与探空廓线的均方根误差分别缩小约9.09%和14.01%;探空气球飘移对本文LAPS分析场检验影响不明显。进一步将LAPS分析场用于2011年8月13日、2014年8月4日两次局地对流个例分析表明:LAPS高时空分辨率的分析场能够反映中小尺度天气系统的时空变化,在天气尺度背景并不十分有利于对流生成的情况下,热岛、海陆风环流的形成和持续对上海夏季局地对流天气的发生和发展起到关键作用。

This paper first conducts the research of localization of the Local Analysis and Prediction System(LAPS)in Shanghai based on ground automatic station,sounding,radar and satellite data and than refers to the six typical local weather cases in summer from 2010 to 2014 to verify and evaluate its performance.The results indicate that the radar radial wind data have a great impact on LAPS wind speed analysis,reducing the root mean square error of the wind speed profile and the sounding profile in the analysis field by about 7.66%;Fengyun satellite data can improve LAPS temperature and relative humidity,reducing the root mean square errors of temperature profile and sounding profile and of relative humidity profile and sounding profile in the analysis field by about 9.09%and 14.01%respectively;the effect of sounding balloon drift is not obvious on LAPS analysis field evaluation.The paper further uses LAPS analysis fields in analysis of two local convective weather cases(13,Aug.2011 and 4,Aug.2014).The results show that the high temporal and spatial resolution analysis field of LAPS can represent temporal and spatial changes of mesoscale and microscale weather systems.In the case that the synoptic scale background is not very conducive to convection generation,the generation and continuation of urban heat island and lsea-land breeze circulation play an important role in development of local convective weather in summer in Shanghai.