2015年春季华北黄淮等地一次沙尘天气过程分析

Analysis of a Sand and Dust Weather Process Affecting North China and Huanghuai in Spring 2015

利用常规气象观测资料、环境观测资料和ECMWF预报模式、CUACE/dust沙尘模式等资料和预报结果,对2015年3月27—30日华北、黄淮等地沙尘天气过程的天气形势、形成原因和模式预报等结果进行了分析,结果表明:此次沙尘天气过程由东北气旋快速变化引起的冷空气南下造成了华北、黄淮等地的沙尘天气,而后活跃的暖空气盛行一支南风把沙尘又携带返回传输至华北、黄淮一带地区;预报员对这种天气形势的快速变化预计不够充分,加之数值模式对正北路径的漏报,致使对28日的华北、黄淮等地大面积沙尘强度及区域预报偏弱,而后预报员和模式也没有充分考虑南风造成的沙尘从南向北回流传输情况的影响,特别是霾天气的同步发展更容易造成对沙尘天气的忽略,所以春季应通过PM_(10)和PM_(2.5)浓度的同时检测来辨识沙尘、霾和混合型天气,通过首要污染物是否为PM_(10)来判断主要污染类型。

By using conventional data and simulation results from models of European Centre for MediumRange Weather Forecasts（ECMWF）and Chinese Unified Atmospheric Chemistry Environment Dust（CUACE/Dust）,the weather situation,causes and forecasting results of the sand and dust weather process from 27 to 30 March 2015 were analyzed.This sand and dust weather in North China and Huanghuai Region of China resulted from the southward moving of cold air caused by rapid changes of northeast cyclone.And then,active warm air from southern regions brought the dust back to the north.Forecasters’ inadequate estimation to the rapid changes of weather situation and the missing forecasting of the dust from the northern path by numerical models led to the underestimation of the strength and coverage area of the dust storm in North China and Huanghuai Region of China on 28 March.Moreover,the back transport of dust from south to north was not fully considered by both forecasters and models,especially in haze days.Thus,dusty,hazy,and the mixed weathers should be identified by observing the concentrations of PM10 and PM2.5 in spring,and pollution types could be judged by whether the primary pollutants were PM10 or not.