对新冠疫情严控期间河北省空气质量的评估

Evaluation of Air Quality in Hebei Province During the Strict Control of COVID-19

为探索2020年新冠肺炎疫情期间企业、工厂停工停产对空气质量的影响,利用2013~2020年间2、3月AQI、SO_(2)、NO_(2)、CO、PM2.5、PM10、O3等空气污染数据和风向风速、相对湿度等气象观测资料,采用比较分析法和克里金空间插值法对AQI等主要大气污染物的时、空特征及变化趋势等进行了对比分析。结果表明,2020年空气质量有明显的好转,中南部地区AQI指数和污染物浓度均有大幅度下降,北部地区有小幅上升;各首要污染物变化不同,其中NO_(2)、SO_(2)的站次和占比显著下降,而O3、PM10、PM2.5占比均有不同程度的增加;全省范围日平均浓度积聚速度和日增长比例均有不同程度的下降,消散速度变化不明显;小时平均浓度日变化振幅随年份逐渐减小,减小值从南向北呈递减趋势;重度、严重污染持续时间较往年显著变短,污染物高浓度值面积明显减小,以中南部和东部地区最为显著。调控的效果区域性差异较大,中南部和东部地区需完善调控措施、加大调控力度;另外,不同污染物的调控效果也有差异,应增加针对NO_(2)、SO_(2)的减排措施,为河北省重污染天气调控措施的完善提供了科学依据。

In order to explore the impact of suspension of work and production on air quality during the 2020 coronavirus pandemic,in this paper,based on the air pollution data of AQI,SO2,NO2,CO,PM2.5,PM10,O3,and the meteorological observation data of wind direction,wind speed,relative humidity in February and March during 2013~2020,the temporal and spatial characteristics and variation trend of AQI and other major atmospheric pollutants were analyzed by using comparative analysis method and Kriging spatial interpolation method.The results showed that air quality improved significantly in 2020.The AQI index and the concentration of pollutants have decreased significantly in the central and southern regions,while increased slightly in the northern regions.The changes in the primary pollutants are different,the number and proportion of NO2 and SO2 decreased significantly,while the proportions of O3,PM10,and PM2.5increased to varying degrees.The province-wide daily average concentrationaccumulation rate and daily growth rate have decreased in different degrees,and the dissipation rate did not change significantly.The amplitude of diurnal variation of hourly mean concentration decreased gradually with the year,and the decreasing value showed a decreasing trend from south to north.The duration of severe and severe pollution was significantly shorter than that in previous years,and the area with high pollutant concentration values was significantly reduced,especially in central,southern and eastern regions.The analysis results showed that the effects of control measures vary greatly from region to region.The central and southern and eastern regions need to improve control measures and enhance control efforts.In addition,the control effects of different pollutants were also different,and reduction measures for NO2and SO2should be increased.This research provides a scientific basis for improving control measures of heavy pollution weather in Hebei Province.