黄河金三角地区城市O_(3)污染的时空格局演变特征

Spatiotemporal Pattern and Characteristics of O_(3) Pollution in the Yellow River Golden Triangle Demonstration Urban Area

黄河金三角地区空气质量的改善是践行黄河流域生态保护和高质量发展的体现,科学认识O_(3)浓度时空演变和污染特征对于该地区大气污染联防联控具有重要意义.本研究融合地面观测和卫星遥感反演O_(3)浓度数据,采用统计分析、趋势分析及热点分析的方法揭示黄河金三角地区O_(3)浓度的年、季节和月尺度以及空间变化特征,探究O_(3)污染等级的变化特征.结果表明:①黄河金三角地区2015−2022年4个地级市大气中O_(3)浓度呈升高趋势,O_(3)年均浓度表现为运城市(105μg/m^(3))>临汾市(103μg/m^(3))>三门峡市(97μg/m^(3))>渭南市(95μg/m^(3)).②O_(3)季均浓度总体表现为夏季(146μg/m^(3))>春季(113μg/m^(3))>秋季(83μg/m^(3))>冬季(59μg/m^(3)).③1−12月O_(3)浓度呈现抛物线的变化特征(5−9月偏高).④空间分布上,O_(3)浓度最大值和平均值的高值区域主要分布在黄河金三角地区东北到西南方向,低值区域分布在西北和东南方向,O_(3)浓度最小值的空间分布特征与此相反.⑤黄河金三角地区1−12月O_(3)浓度在北部、中部和南部均呈现高值和低值交替出现的空间聚集特征.NPP/VIIRS-O_(3)聚集区主要分布在该地区北部的5个区县,GDP-O_(3)聚集区零散分布在该地区的7个区县.⑥2015−2022年黄河金三角地区4个地市O_(3)不同污染等级的天数表现为优良(199 d)>轻度污染(123 d)>中度污染(46 d)>重度污染(7 d)>严重污染(0 d),优良和轻度污染的天数较多且优良的天数占到50%以上,轻度污染和中度污染出现的天数表现为夏季(77 d)>春季(58 d)>秋季(27 d)>冬季(6 d),优良的季节性变化特征则正好相反.研究成果对于揭示黄河金三角地区O_(3)时空演变规律及污染特征,制定科学合理的防治措施具有现实意义.

The improvement of air quality in the Yellow River Golden Triangle Demonstration Area(YRGTDA)is a reflection of ecological protection and high-quality development in the Yellow River Basin.Understanding the spatiotemporal evolution of O_(3)concentration and pollution characteristics is important for the prevention and control of air pollution in this region.In this study,ground truth observations and remote sensing inversion of O_(3)concentration data were both used,and then statistical analysis,trend analysis,and hotspot analysis methods were used to reveal the changing characteristics of O_(3)concentration on annual,seasonal,monthly,and spatial scales,and the changes in O_(3)pollution levels were investigated.The results showed that:(1)Annually,the atmospheric O_(3)concentration from 2015 to 2022 in the four cities in the Yellow River Golden Triangle Demonstration area showed an upward trend,and followed the order of Yuncheng(105μg/m^(3))>Linfen(103μg/m^(3))>Sanmenxia(97μg/m^(3))>Weinan(95μg/m^(3)).(2)Seasonally,the O_(3)concentration followed the order of summer(146μg/m^(3))>spring(113μg/m^(3))>autumn(83μg/m^(3))>winter(59μg/m^(3)).(3)Monthly,O_(3)concentration showed a parabolic variation,with high values in June and low values in January and December.(4)Spatially,the high values of the highest and average O_(3)concentrations were mainly distributed from the northeast to the southwest,and the low values were mainly distributed in the northwest and southeast,while this was opposite for the minimum O_(3)concentrations.(5)From January to December,the O_(3)concentration in the Yellow River Golden Triangle Demonstration Area showed spatial clustering patterns of changes in alternating high and low values in the north,central and south.The NPP/VIIRS-O_(3)agglomeration was mainly located in five counties in the northern part of the region,and the GDP-O_(3)agglomeration was scattered in seven counties in the region.(6)The number of days with different levels of O_(3)pollution in the Yellow River Golden Triangle Demonstration Area followed the order of excellent(199 d)>lightly polluted(123 d)>moderately polluted(46 d)>heavily polluted(7 d)>severely polluted(0 d).The number of days with excellent and lightly polluted were high and the number of days with excellent accounted for more than 50%.The variation of the number of days with the lightly polluted and moderately polluted showed summer(77 d)>spring(58 d)>autumn(27 d)>winter(6 d),while it′s opposite for excellent level.The results of this study are of great theoretical and practical significance to reveal the spatiotemporal variations of O_(3)concentrations and pollution characteristics in the Yellow River Golden Triangle Demonstration Area,and to the implement of scientific and reasonable prevention and control measures.