Use of MODIS-derived surface reflectance data in the ORAC-AATSR aerosol retrieval algorithm: Impact of differences between sensor spectral response functions

Abstract The aerosol component of the Oxford-Rutherford Appleton Laboratory (RAL) Aerosol and Clouds (ORAC) retrieval scheme for the Advanced Along-Track Scanning Radiometer (AATSR) uses data derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) to constrain the brightness of the surface. However, the spectral response functions of the channels used (centred near 550 nm, 660 nm, 870 nm, and 1.6 μm) do not exactly match between the two sensors. It is shown that failure to account for differences between the instruments' spectral response functions leads to errors of typically 0.001–0.01 in spectral surface albedo, and distinct biases, dependent on wavelength and surface type. A technique based on singular value decomposition (SVD) is used to reduce these random errors by an average of 35% at 670 nm and over 60% at the other wavelengths used. The technique reduces the biases so that they are negligible. In principle, the method can be extended to any combination of sensors. The SVD-based scheme is applied to AATSR data from the month of July 2008 and found to increase the number of successful aerosol retrievals, the speed of retrieval convergence, and improve the level of consistency between the measurements and the retrieved state. Additionally, retrieved aerosol optical depth at 550 nm shows an improvement in correspondence when compared to Aerosol Robotic Network (AERONET) data.

[1]  Michael D. King,et al.  Aerosol properties over bright-reflecting source regions , 2004, IEEE Transactions on Geoscience and Remote Sensing.

[2]  Clive D Rodgers,et al.  Inverse Methods for Atmospheric Sounding: Theory and Practice , 2000 .

[3]  W. V. Hoyningen-Huene,et al.  Retrieval of aerosol optical thickness over land surfaces from top‐of‐atmosphere radiance , 2003 .

[4]  John P. Burrows,et al.  Retrieval of spectral aerosol optical thickness from multi-wavelength space-borne sensors , 2002 .

[5]  S. Hook,et al.  The ASTER spectral library version 2.0 , 2009 .

[6]  Gerrit de Leeuw,et al.  Retrieval of aerosol optical depth over land using two‐angle view satellite radiometry during TARFOX , 1998 .

[7]  Alan H. Strahler,et al.  Consistency of MODIS surface bidirectional reflectance distribution function and albedo retrievals: 1. Algorithm performance , 2003 .

[8]  A. Kokhanovsky,et al.  Satellite Aerosol Remote Sensing Over Land , 2009 .

[9]  Larry D. Travis,et al.  Capabilities and limitations of a current FORTRAN implementation of the T-matrix method for randomly oriented, rotationally symmetric scatterers , 1998 .

[10]  T. Eck,et al.  Variability of Absorption and Optical Properties of Key Aerosol Types Observed in Worldwide Locations , 2002 .

[11]  Peter R. J. North,et al.  The inter-comparison of major satellite aerosol retrieval algorithms using simulated intensity and polarization characteristics of reflected light , 2009 .

[12]  Caroline Poulsen,et al.  Calibration status of the AATSR reflectance channels , 2008 .

[13]  T. Painter,et al.  Reflectance quantities in optical remote sensing - definitions and case studies , 2006 .

[14]  P. Bhartia,et al.  Derivation of aerosol properties from satellite measurements of backscattered ultraviolet radiation , 1998 .

[15]  A. Smirnov,et al.  AERONET-a federated instrument network and data archive for aerosol Characterization , 1998 .

[16]  E. Vermote,et al.  Second‐generation operational algorithm: Retrieval of aerosol properties over land from inversion of Moderate Resolution Imaging Spectroradiometer spectral reflectance , 2007 .

[17]  Richard Siddans,et al.  Oxford-RAL Aerosol and Cloud (ORAC): aerosol retrievals from satellite radiometers , 2009 .

[18]  John P. Burrows,et al.  The detection of cloud-free snow-covered areas using AATSR measurements , 2010 .

[19]  Michael J. Barnsley,et al.  Global retrieval of bidirectional reflectance and albedo over land , 1997 .

[20]  Alan H. Strahler,et al.  Quality assessment of BRDF/albedo retrievals in MODIS operational system , 2008 .

[21]  Nadine Gobron,et al.  Using angular and spectral shape similarity constraints to improve MISR aerosol and surface retrievals over land , 2005 .

[22]  P. Koepke,et al.  Optical Properties of Aerosols and Clouds: The Software Package OPAC , 1998 .

[23]  Peter R. J. North,et al.  Estimation of aerosol opacity and land surface bidirectional reflectance from ATSR‐2 dual‐angle imagery: Operational method and validation , 2002 .

[24]  Alan H. Strahler,et al.  An algorithm for the retrieval of albedo from space using semiempirical BRDF models , 2000, IEEE Trans. Geosci. Remote. Sens..

[25]  N. C. Strugnell,et al.  First operational BRDF, albedo nadir reflectance products from MODIS , 2002 .

[26]  A. Dudhia,et al.  Aerosol Remote Sensing Using AATSR , 2006 .

[27]  Corinne Le Quéré,et al.  Climate Change 2013: The Physical Science Basis , 2013 .

[28]  Yanmin Shuai,et al.  Validation of Moderate Resolution Imaging Spectroradiometer (MODIS) albedo retrieval algorithm: Dependence of albedo on solar zenith angle , 2009 .

[29]  R. Betts,et al.  Changes in Atmospheric Constituents and in Radiative Forcing. Chapter 2 , 2007 .

[30]  Ulrich Bundke,et al.  Chemical composition and complex refractive index of Saharan Mineral Dust at Izaña, Tenerife (Spain) derived by electron microscopy , 2007 .

[31]  Jochen Landgraf,et al.  Retrieval of aerosol properties over land surfaces: capabilities of multiple-viewing-angle intensity and polarization measurements. , 2007, Applied optics.

[32]  Roy G. Grainger,et al.  Atmospheric Measurement Techniques A sea surface reflectance model for ( A ) ATSR , and application to aerosol retrievals , 2010 .

[33]  Bryan Lawrence,et al.  The GRAPE aerosol retrieval algorithm , 2009 .

[34]  Bernard Pinty,et al.  Techniques for the retrieval of aerosol properties over land and ocean using multiangle imaging , 1998, IEEE Trans. Geosci. Remote. Sens..

[35]  A. Strahler,et al.  On the derivation of kernels for kernel‐driven models of bidirectional reflectance , 1995 .

[36]  C. Woodcock,et al.  Consistency of MODIS surface bidirectional reflectance distribution function and albedo retrievals: 2. Validation , 2003 .

[37]  A. Kokhanovsky,et al.  Aerosol remote sensing over land: A comparison of satellite retrievals using different algorithms and instruments , 2007, Atmospheric Research.

[38]  Alan H. Strahler,et al.  Validation of the MODIS bidirectional reflectance distribution function and albedo retrievals using combined observations from the aqua and terra platforms , 2006, IEEE Transactions on Geoscience and Remote Sensing.

[39]  R. Colwell Remote sensing of the environment , 1980, Nature.

[40]  B. Stevens,et al.  Untangling aerosol effects on clouds and precipitation in a buffered system , 2009, Nature.

[41]  S. J. Sutley,et al.  USGS Digital Spectral Library splib05a , 2003 .