基于高光谱技术的广州市HCHO时空分布和来源定量遥感研究  

Quantitative remote sensing study on the spatiotemporal distribution and sources of HCHO in Guangzhou based on hyperspectral technology

作　　者：魏少聪 邢成志 林继楠 宋宇航 胡启后 季祥光 滕佳华 徐宁宁 刘诚 WEI Shaocong;XING Chengzhi;LIN Ji’nan;SONG Yuhang;HU Qihou;JI Xiangguang;TENG Jiahua;XU Ningning;LIU Cheng(Department of Precision Machinery and precision Instrumentation,University of Science and Technology of China,Hefei 230026,China;Key Laboratory of Environmental Optics&Technology,Anhui Institute of Optics and Fine Mechanics,Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei 230031,China;State Environmental Protection Key Laboratoryof Satellite Remote Sensing,Ministry of Ecology and Environment Center for Satellite Application on Ecology and Environment,Beijing 100094,China;Information Materials and Intelligent Sensing Laboratory of Anhui Province,Anhui University,Hefei 230039,China)

机构地区：[1]中国科学技术大学精密机械与精密仪器系,合肥230026 [2]中国科学院合肥物质科学研究院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室,合肥230031 [3]生态环境部卫星环境应用中心/国家环境保护卫星遥感实验室,北京100094 [4]安徽大学信息材料与智能感知安徽省实验室,合肥230039

出　　处：《遥感学报》2023年第8期1844-1855,共12页NATIONAL REMOTE SENSING BULLETIN

基　　金：国家重点研发计划(编号:2019YFC0214702);国家自然科学基金(编号:U21A2027);安徽省自然科学基金(编号:2108085QD180)。

摘　　要：甲醛(HCHO)作为一种重要的大气污染物,不仅会影响区域大气环境质量,还会对人体健康造成危害。然而,目前HCHO的监测手段依然以地面监测为主,缺乏垂直观测阻碍了人们对HCHO垂直演化和高空大气化学过程的深入认识。本文基于搭设于广州地球化学研究所高光谱设备的观测数据,通过最优估计反演算法获得了2020年12月至2021年11月期间的HCHO垂直廓线。研究发现,广州市HCHO浓度在垂直方向呈现出边界层底层(6.61 ppb)>边界层中层(4.76 ppb)>边界层顶层(3.00 ppb);在时间上表现为夏季(8.58 ppb)>春季(8.50 ppb)>秋季(8.05 ppb)>冬季(5.43 ppb);不同季节的HCHO垂直日变化特征相似,最高浓度均出现在200 m且呈现出“双峰”变化模式,第一个峰值出现在08:00—10:00,第二个峰值出现在14:00左右。此外,基于遥感数据建立多元线性回归模型实现了对观测期间HCHO背景浓度、一次和二次来源浓度的剥离。研究发现,整个观测期间HCHO二次源浓度(约占64.10%)>背景浓度(约占20.20%)>一次源浓度(约占15.70%);此外,受VOCs排放浓度与光化学反应强度的影响,夏季二次HCHO浓度占比明显高于冬季。通过对HCHO周末与工作日的垂直日变化特征进行分析,得出广州周末HCHO排放水平并没有表现出明显的下降。本研究可加强对HCHO时空分布特征的深入认识,为污染防控措施的制定提供数据支持。As an important air pollutant,formaldehyde(HCHO)not only affects the quality of the regional atmospheric environment but also harms human health.However,the current monitoring methods for HCHO are mainly based on surface in situ measurements,and the lack of vertical observations significantly hinders an in-depth understanding of the vertical evolution and chemical processes of HCHO,especially in the upper atmosphere.In this study,we retrieved HCHO vertical profiles by using the optimal estimation method(OEM)and hyperspectral remote sensing instrument measurements in Guangzhou Institute of Geochemistry(CAS)from December 2020 to November 2021.The HCHO in the vertical direction varied in the order of lower boundary layer(6.61 ppb)>middle boundary layer(4.76 ppb)>upper boundary layer(3.00 ppb).For the seasonal variation,HCHO varied in the order of summer(8.58 ppb)>spring(8.50 ppb)>autumn(8.05 ppb)>winter(5.43 ppb).The HCHO profiles in different seasons showed similarities in their diurnal variation characteristics.The highest HCHO concentrations usually appeared at 200 m and exhibited a“bi-peak”pattern,with the first peak occurring at 08:00—10:00 and the second occurring around 14:00.We also established a multiple linear regression model based on hyperspectral remote sensing instrument data to classify the measured HCHO to background,primary,and secondary concentrations.The HCHO secondary concentration(~64.10%)was the highest,followed by the background concentration(~20.20%)and primary concentration(~15.70%).The proportion of secondary HCHO in summer was significantly higher than that in winter mainly due to the enhanced VOCs emissions and reactivity of the photochemical process.By analyzing the diurnal variations of HCHO profiles on weekdays and weekends,we concluded that the HCHO emission level in Guangzhou did not significantly decrease during weekends.This study can help further understand the tempo-spatial distribution characteristics of HCHO and provide data support for the formulation of pollution preven

关 键 词：遥感 高光谱技术 甲醛 垂直分布 季节变化 二次源 周末效应 广州市 

分 类 号：P2[天文地球—测绘科学与技术]