基于CMA-MESO三维变分系统的化学同化框架设计及气溶胶观测的初步分析预报试验  

Construction of a chemistry-weather assimilation system coupled with CMA-MESO and preliminary experiments assimilating aerosol observations

作　　者：庄照荣[1,2] 王皓 田伟红[1,2] 李兴良[1,2] ZHUANG Zhaorong;WANG Hao;TIAN Weihong;LI Xingliang(CMA Earth System Modeling and Prediction Centre,Beijing 100081,China;State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China)

机构地区：[1]中国气象局地球系统数值预报中心,北京100081 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081

出　　处：《气象学报》2023年第3期456-468,共13页Acta Meteorologica Sinica

基　　金：国家自然科学基金重大项目(42090032)。

摘　　要：CMA-CUACE-Haze化学天气模式是中国研发的气溶胶过程模拟和评估工具,但目前还没有配套的大气化学天气耦合同化分析系统。文中在CMA-MESO三维变分分析的基础上建立了区域化学天气耦合同化系统,该系统把变量之间不相关的PM_(2.5)和PM_(2.5-10)作为控制变量,采用模型化的背景误差协方差,初步实现气溶胶观测PM_(2.5)和PM_(10)的同化分析。通过单站气溶胶观测的理想同化试验验证耦合同化系统设计的合理性,并针对2016年12月的重污染天气过程进行GTS传输的常规观测与气溶胶PM_(2.5)和PM_(10)观测资料同化与预报试验。试验结果表明,大气化学天气耦合同化系统可对气溶胶观测和天气变量观测同时进行极小化分析,大气化学变量和天气变量分析场互不影响;气溶胶观测资料的同化合理修正了大气化学背景场,PM_(2.5)和PM_(10)变量分析场更接近观测;气溶胶观测资料同化对污染物预报的影响可持续72 h。搭建的区域化学天气耦合同化系统能为CMA-CUACE-Haze化学天气模式提供更准确的化学初始场。The CMA-CUACE-Haze atmospheric chemistry model developed in China is an important tool for aerosol process simulation and assessment,yet there is a lack of atmospheric chemistry variable analysis system.In this paper,an assimilation system for regional chemical weather coupling based on the CMA-MESO three-dimensional variational analysis is developed,which takes uncorrelated PM_(2.5) and PM_(2.5-10) variables as control variables and utilizes the modeled background error covariance to achieve assimilation analysis of aerosol observations of PM_(2.5) and PM_(10).The validity of the design of the coupled assimilation system is verified by aerosol single-station ideal tests,and assimilation experiment of aerosol PM_(2.5) and PM_(10) observations has been conducted for the heavy pollution process in December 2016.The analysis results indicate that the coupled atmospheric chemistry-weather assimilation system can perform simultaneous miniaturization analysis of aerosol observations and weather variable observations,and the analysis fields between atmospheric chemistry variables and weather variables do not affect each other.The assimilation of aerosol observations reasonably corrects the atmospheric chemical background field,and the analytical fields of PM_(2.5) and PM_(10) variables are closer to the observations.Aerosol assimilation has a significant effect on pollutant forecasts and the effect can last up to 72 h.The regional coupled chemistry-weather assimilation system developed in this study can provide more accurate chemical initial fields for the CMA-CUACE-Haze model.

关 键 词：气溶胶观测同化 三维变分 CMA-CUACE-Haze PM_(2.5) PM_(10) 

分 类 号：P402[天文地球—大气物理学与大气环境]