基于OMI及地面监测的贵州省污染气体浓度时空差异研究

Temporal-spatial difference of pollutant gases in Guizhou Province based on OMI and ground data

贵州省属于典型的喀斯特山区,受地势和气候影响,省内不同区域污染气体浓度具有明显的时空差异。因此,利用交互式数据语言(IDL)+遥感图像处理平台ENVI、地理信息系统软件ArcGIS等,基于臭氧层监测仪(OMI)的L3V003柱浓度数据和地面环境监测站数据,从时间和空间两个方面在区域尺度上评估分析了贵州省3种主要污染气体的浓度变化差异和时空演变特征。结果表明:(1)2019年,贵州省二氧化氮(NO_(2))、二氧化硫(SO_(2))、臭氧(O_(3))柱浓度较2005年呈下降趋势,且两种方法监测的NO_(2)、SO_(2)季节特征均表现为“秋冬高、春夏低”,受太阳辐射和天气过程影响,两种方法监测的O_(3)均表现为“春夏高、秋冬低”的季节特征;(2)对比分析表明,遥感方法反演的NO_(2)柱浓度极大值和SO_(2)柱浓度极小值较地面监测结果在时间上存在滞后性,但滞后时间较短,没有出现跨季节差异,总体上空间差异性大于时间差异性,且SO_(2)夏季空间差异性大于冬季;(3)自然界平流层中含有大量臭氧,且夏季贵州雷雨天气较多,在天气过程发生时,高层氧气极易被大量分解并生成O_(3),由于大气垂直输送较为活跃,使得平流层O_(3)稳定性降低,对近地面浓度影响较大,因此遥感反演的O_(3)浓度与地面监测结果在时间和空间上均有明显差异性。

Guizhou Province of China belongs to a typical karst mountainous area,and due to the influence of terrain and climate,there are obvious spatial and temporal differences in the concentration of polluting gases in different regions of the province.Therefore,based on L3 V003 column amount data from the Ozone Monitoring Instrument(OMI)and the ground environmental monitoring station data,the spatio-temporal differences in the concentration changes and the spatiotemporal evolution characteristics of the three main pollutants in Guizhou Province were analyzed and evaluated at the regional scale,using interactive data language(IDL)plus the remote sensing image processing platform ENVI,geographic information system software ArcGIS,etc.The results show that:(1)The NO_(2),SO_(2) and O_(3) column amount in Guizhou Province in 2019 show a downward trend compared to 2005.The seasonal characteristics of NO_(2) and SO_(2) concentration monitored by the two methods both show high in autumn and winter,and low in spring and summer.While due to the influence of solar radiation and weather processes,O_(3) concentration monitored by the two methods show the same seasonal characteristics of"high in spring and summer,low in autumn and winter".(2)Both the maximum NO_(2) column amount and the minimum SO_(2) column amount monitored by remote sensing have a lag in time campared to ground monitoring results,but the lag time is short and there is no cross seasonal difference.Overall,their spatial differences are greater than temporal differences,and the spatial differences of SO_(2) concentration in summer are greater than in winter.(3)The stratosphere contains a lot of ozone in nature,and there are more thunderstorms in Guizhou Province in summer,so when the weather process occurs,oxygen in the high atmosphere is easily decomposed to generate O_(3) in large quantities.Due to the active vertical atmospheric transport,the stability of stratospheric O_(3) is reduced,which has a greater impact on the near-surface O_(3) concentration.Therefore,the O_(3) column amount monitored by remote sensing and the ground monitoring results are significantly different in time and space.