福建省2005—2017年大气边界层SO2的时空变化特征

Temporal and Spatial Variation Characteristics of Atmospheric PBL SO2 in Fujian Province from 2005 to 2017

为研究近年来福建省SO2污染的时空动态特征,利用臭氧观测仪(ozone monitoring instrument,OMI)卫星遥感反演的PBL(planetary boundary layer,大气边界层) SO2柱含量数据,分析了2005—2017年福建省PBL SO2柱含量的时空间分布特征.结果表明:①在长时间尺度上,PBL SO2柱含量的变化趋势可分为2个时段,其中,2005—2011年PBL SO2柱含量呈逐渐上升趋势,6 a增加了约0. 027 DU,增长率约为6. 12%;2011—2017年PBL SO2柱含量呈下降趋势,7 a减少了约0. 018 DU,下降率约为3. 89%.②PBL SO2柱含量呈明显的周期性变化特征,最小值和最大值分别出现在6月和12月,多年平均值分别约为0. 383和0. 555 DU.③PBL SO2柱含量的3个高值区分别出现在沿海的福州市,厦门市、漳州市东部和泉州市西部,三明市和南平市部分地区,这3个高值区多年平均PBL SO2柱含量分别约为0. 505、0. 495和0. 485 DU.从城市尺度上来看,PBL SO2柱含量最大值出现在厦门市,其多年平均值为(0. 486±0. 015) DU;其次为福州市,PBL SO2柱含量多年平均值为(0. 465±0. 026) DU;最低值出现在漳州市,PBL SO2柱含量多年平均值为(0. 429±0. 020) DU.④福建省PBL SO2柱含量变化趋势在空间分布上存在明显的差异,不同时期、不同区域变化趋势不一致.2005—2011年PBL SO2柱含量的变化范围为-0. 13~0. 18 DU,变化率范围为-25%~50%,PBL SO2柱含量出现增长的区域主要是在高值区,如龙岩市西部、厦门市北部以及三明市东部等区域;2011—2017年PBL SO2柱含量的变化范围为-0. 13~0. 15 DU,变化率范围为-29%~34%. 2011—2017年福州市和厦门市PBL SO2柱含量下降最为明显,减少了约0. 10 DU,下降率约为25%.研究显示,卫星遥感估算的PBL SO2柱含量具有一定的可靠性,可以用于区域SO2污染的研究.

Human activities have discharged a large amount of polluting gases into the atmosphere in recent years,resulting in a high concentration of tropospheric SO2.High concentration of SO2 seriously affects human health,and causes damages to terrestrial ecosystems and the environment.Satellite remote sensing has the advantages of wide coverage,periodic observation capability and continuous spatial monitoring,which has made satellite remote sensing an important research tool for studying the temporal and spatial variation characteristics of regional SO2 pollution in the atmosphere.We analyzed the spatial distribution and temporal evolution trend of PBL SO2 in Fujian province using the satellite retrieved data from the Ozone Monitoring Instrument(OMI)sensor.The results showed that:(1)The regression analysis results indicate that the estimation data from OMI has certain stability.There is a moderate correlation between PBL SO2 and ground-based observation SO2,and the PBL SO2 data can be used for the research of regional SO2 pollution.In the long term,the evolution trend of PBL SO2 is divided into two periods:it showed a gradual upward trend from 2005 to 2011,and PBL SO2 increased by approximately 0.027 DU,about 6.12%compared to data in 2005;it showed a downward trend from 2011 to 2017,and PBL SO2 decreased by about 0.018 DU,approximately 3.89%compared to data in 2011.(2)The regional PBL SO2 also showed obvious annual variation.The minimum and maximum values appear in June and December,and the multi-year averaged values are approximately0.383 and 0.555 DU,respectively.(3)The three high value regions of PBL SO2 mainly appear along the coast of Fuzhou City,Xiamen,eastern Zhangzhou,western Quanzhou,and some areas of Sanming and Nanping.The multi-year averaged PBL SO2 for these three regions are approximately 0.505,0.495 and 0.485 DU,respectively.From the urban scale,the maximum value appears in Xiamen City.The PBL SO2 is(0.486±0.015)DU,followed by Fuzhou,where the PBL SO2 is(0.465±0.026)DU.(4)There is a significant difference in the spatial distributions of PBL SO2 evolution trends in Fujian province,and the trends in different periods and regions are inconsistent.The difference variation values of PBL SO2 from 2005 to 2011 ranged from-0.13 DU to 0.18 DU;the percentage range was between-25%and50%.The increased areas are mainly located in high-value areas,such as the western Longyan City,northern Xiamen City,and the eastern Sanming City.The difference variation values of PBL SO2 from 2011 to 2017 ranged from-0.13 DU to 0.15 DU;the percentage range was between-29%and 34%.The decline of PBL SO2 in Fuzhou and Xiamen was the most noticeable from 2011 to 2017,with a reduction of about 0.10 DU,or 25%.The research indicated that the PBL SO2 estimated from satellite remote sensing has certain reliability and can be used for the study of regional SO2 pollution.And the PBL SO2 shows obvious temporal and spatial variation characteristics in Fujian Province.