北京地区持续性大雾的微物理结构观测研究

On the accelerating process of industrialization and urbanization, the fog events in Beijing region is characterized by long duration, extensive range, heavy intensity, which do seriously harm for transportation safety, human health, environment and ecology. However, the observation analysis on the microphysical structure of persistent fog in Beijing is limited for the lack of detection means. Based on the platform of ground observation and remote sensing monitoring in Chinese Academy of Meteorological Sciences, the temporal evolution characteristics of microphysical process of fog droplets and aerosol will be studied in the long-lasting fog event by means of several cloud physics and aerosol instruments. Furthermore, the vertical microphysical structure of liquid water and aerosol will also be investigated with the following remote sensing devices, such as microwave radiometer, lidar, and ceilometer. At last, the formation and evolution process of persistent fog will be reappeared by simulation of Weather Research and Forecasting Model (WRF). The formation mechanism and influencing factors of persistent fog in Beijing are all to be discussed by the analysis of continuous parameters in time and space and sensitivity simulation test. In short, focused on the hot question in the current society, the project is mainly based on observation analysis with most advanced instruments, combined with numerical simulation, which is involved in scientific studies of cloud physics in the background of urban pollution.

随着城市化和工业化进程的加快，北京地区的大雾天气呈现持续时间长、影响范围广、强度大等地域性特点，对交通安全、人类健康和环境生态造成严重的危害，但对北京地区持续性大雾天气的微物理结构的观测研究比较少。本项目拟利用中国气象科学研究院的雾、霾地面观测与遥感探测平台的多种云物理和气溶胶观测资料，开展持续性大雾天气中雾滴和气溶胶等微物理过程的时间演变特征研究，同时利用微波辐射计、激光雷达、云高仪等遥感设备研究持续性大雾过程中液态水和气溶胶的微物理垂直结构特征。最后结合天气预报模式WRF模拟和再现持续性大雾的发展和演变过程，通过时空连续的参量分析和敏感性模拟试验，分析北京地区持续性大雾天气的形成机制和影响因素。本项目结合当今社会的热点问题，使用国际上先进的探测仪器，以观测分析为主，结合数值模拟分析，侧重城市污染背景环境下的云物理过程的科学研究。

考虑到华北地区的持续性大雾（霾）天气对人类健康和交通的重要影响，以北京地区持续性大雾的结构观测为基础，从污染气溶胶、边界层垂直结构和云雾垂直结构三个方面研究了大雾持续性的形成发展机制和影响因素。主要内容包括：1）研究了持续性大雾的演变特征，发现辐射降温、高浓度的污染气溶胶和毛毛雨的增湿对雾霾形成和持续起着重要作用。2）研究了持续性霾和雾霾天气的边界层结构，发现双层逆温结构及上层逆温的下沉对污染天气的持续和加强起着重要的作用。3）研究了持续性大雾的云雾垂直结构特征，模拟结果表明云的辐射效应对边界层大雾的持续发展起着促进作用。该项目以北京地区的空气质量为研究背景，从气溶胶和雾的时间演变、边界层结构和云雾垂直结构研究中揭示了气溶胶、双层逆温和云辐射效应对雾（霾）形成和持续发展的物理机制。