Long-time series aerosol optical depth retrieval from AVHRR data over land in North China and Central Europe

作者:Xue, Y (Xue, Yong)[ 3,4 ] ; He, XW (He, Xingwei)[ 1,2,8 ] ; de Leeuw, G (de Leeuw, Gerrit)[ 5,6 ] ; Mei, LL (Mei, Linlu)[ 4 ] ; Che, YH (Che, Yahui)[ 1,2,8 ] ; Rippin, W (Rippin, Wayne)[ 3 ] ; Guang, J (Guang, Jie)[ 4 ] ; Hu, YC (Hu, Yincui)[ 7 ]

REMOTE SENSING OF ENVIRONMENT

卷: 198  页: 471-489

DOI: 10.1016/j.rse.2017.06.036

出版年: SEP 1 2017

摘要

An algorithm for the retrieval of the aerosol optical depth over land (ADL) using radiances at the top of the atmosphere (TOA) measured by the Advanced Very High Resolution Radiometer (AVHRR) is proposed. AVHRR is the only satellite sensor providing nearly continuous global coverage since June 1979, which could generate the longest aerosol climate data records currently available from operational satellites. In the implementation of the ADL algorithm, an analytical model is used which couples an atmospheric radiative transfer model and a land surface reflectance parameterization. The radiation field can be separated into three parts: direct radiance, single scattered radiance, and multiple-scattered. Each of these parts is individually parameterized. To obtain the surface reflectance in an automatic retrieval procedure over land for AVHRR, the aerosol scattering effect at 3.75 gm was assumed to be negligible and relationships between the surface reflectances at 0.64 mu m and 3.75 mu m were evaluated for different surface types and the authors propose to use these to obtain the surface reflectance at the shorter wavelength. The 0.64 mu m surface reflectance was then used in a radiative transfer model to compute AOD at that wavelength using six different aerosol types, where optimal estimation (OE) theory is applied to minimize the difference between modeled and measured radiances. 

The ADL algorithm is applied to re-calibrated Level 1B radiances from the AVHRRs on-board the TIROS-N and the Metop-B satellites to retrieve the AOD over North China and Central Europe. The results show that the AOD retrieved from these two instruments are in agreement with co-located AOD values from ground-based reference networks. Over North China, using AERONET sites, 58% of the ADLAOD values are within an expected error (EE) range of +/-(0.05 + 20%) and 53% are within the EE range of +/-(0.05 + 15%). For GAW-PFR (World Meteorological Organization, WMO, Global Atmosphere Watch, GAW) sites, part of the European ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure) sites, 79% of the ADL AOD values are within the EE range of +/-(0.05 + 20%) and 75% are within the EE range of +/-(0.05 + 15%). Not surprisingly, the agreement is better over Europe with generally lower AOD values. An additional cross comparison of the AOD results with MODIS (MODerate-resolution Imaging Spectroradiometer) DeepBlue aerosol products shows that the spatial distributions of the two AOD datasets are similar, but with generally lower values for ADL and lower coverage. The temporal variation of the annual mean AOD over selected AERONET sites shows that ADL values are generally between 0.2 and 0.5 over North-Eastem China and trace the MODIS and AERONET data for the overlapping years quite well. (C) 2017 Elsevier Inc. All rights reserved.

通讯作者地址: Xue, Y (通讯作者)

Univ Derby, Coll Engn & Technol, Dept Elect Comp & Math, Derby DE22 1GB, England.

地址:

[ 1 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China

[ 2 ] Chinese Acad Sci, Beijing Normal Univ, Inst Remote Sensing & Digital Earth, Beijing 100101, Peoples R China

[ 3 ] Univ Derby, Coll Engn & Technol, Dept Elect Comp & Math, Derby DE22 1GB, England

[ 4 ] Univ Bremen, Inst Environm Phys, Otto Hahn Allee 1, D-28359 Bremen, Germany

[ 5 ] Univ Helsinki, Dept Phys, Helsinki, Finland

[ 6 ] Finnish Meteorol Inst, Climate Res Unit, Helsinki, Finland

[ 7 ] Hebei Normal Univ, Coll Resources & Environm Sci, Hebei Key Lab Environm Change & Ecol Construct, Shijiazhuang, Hebei, Peoples R China

[ 8 ] Univ Chinese Acad Sci, Beijing 100049, Peoples R China