摘要
静稳天气与大气重污染的发生有紧密联系,为定量描述大气的静稳程度,文章研发了静稳天气综合指数。结合统计和预报经验,挑选发生大气污染的气象要素及其阈值条件,通过权重求和得到初步构建静稳天气指数(SWI)。此后,基于近13年的气象数据,分段统计各气象要素不同区间内雾-霾天气出现概率相对气候态的倍数作为分指数,根据分指数最大值和最小值的比值排序,得到10个对静稳天气具有较强指示意义的气象要素,对这10个要素的分指数求和得到静稳天气指数。改进后的指数和PM_(2.5)浓度有更好的相关性。以2015年1月一次重污染过程为例,分析不同阶段SWI和AQI指数的变化,两者具有较好的一致性,均表现出发展阶段稳定增长,消散阶段迅速降低的特征。应用静稳天气指数评估发现,APEC减排期间京津冀地区大气静稳程度和减排之前相当,但污染持续时间和峰值强度较减排前明显降低。SWI可以在重污染天气预报和重大活动减排措施评估中得到有效应用。
Stable weather index （SWI） of Beijing is developed to meet the demand of quantitative descrip- tion of the degree of stable weather which is conducive to the formation of fog and haze in China. During a heavily polluting process in January 2015, both the SWI and AQI （air quality index） showed consistent trend： stable growth in the developing stage and rapid decrease in the ending stage. SWI is also used to as sess the effect of reduction measure of pollution source. Under the similar stable weather as described by SWI, reduction measures contained air pollution in Beijing during APEC. SWI is developed further based on meteorological data lasting 13 years. Subindex of any parameters is defined as the conditional probabili ty of fog-haze divided by the climatology probability when the threshold of the parameter is met. The top 10 stable-weather-implication parameters are chosen, of which subindexes are added up as the final SWI. The developed SWI shows better correlation with PM2.5 concentration which means better characterization of stable weather.
出处
《气象》
CSCD
北大核心
2017年第8期998-1004,共7页
Meteorological Monthly
基金
科技部国家重点研发计划项目(2016YFC0203301)
气象关键技术集成与应用项目(CMAGJ2015M70)
国家科技支撑计划项目(2014BAC16B02)
公益性行业(气象)科研专项(GYHY201306015)共同资助
