A new algorithm to determine the spectral aerosol optical depth from satellite radiometer measurements

A new aerosol retrieval algorithm is presented which computes the spectral optical depth over the ocean from spaceborne radiometers. It includes both multiple scattering and the bi-directional reflectance of the ocean surface. The previous termalgorithmnext term is applied to data from the Along Track Scanning Radiometer 2 (ATSR-2). This radiometer aboard the ERS-2 satellite has 4 bands in the visible and near-infrared. The ATSR-2 has a dual view capability: the reflectance is measured both at nadir and at a forward angle of approximately 55° along track. This feature is used to test the algorithm by comparing independent retrievals from the forward and the nadir view, applied to Southern Hemisphere data from 23 July 1995. The retrieved aerosol optical depths compare favorably. The retrieved aerosol optical depths and spectral behavior are in agreement with expected values in clean marine environments.

[1]  P Koepke,et al.  Effective reflectance of oceanic whitecaps. , 1984, Applied optics.

[2]  A. Morel.  Optical modeling of the upper ocean in relation to its biogenous matter content (case I waters) , 1988 .

[3]  Kenneth L. Davidson,et al.  The naval oceanic vertical aerosol model: progress report , 1990 .

[4]  R. Reynolds,et al.  The NCEP/NCAR 40-Year Reanalysis Project , 1996, Renewable Energy.

[5]  Gerrit de Leeuw,et al.  Modeling Of Aerosols In The Marine Mixed-Layer , 1989, Defense, Security, and Sensing.

[6]  W. D. Rooij,et al.  Expansion of Mie scattering matrices in generalized spherical functions , 1984 .

[7]  D. Tanré,et al.  Remote sensing of aerosol properties over oceans using the MODIS/EOS spectral radiances , 1997 .

[8]  Edward C. Monahan,et al.  Optimal Power-Law Description of Oceanic Whitecap Coverage Dependence on Wind Speed , 1980 .

[9]  H. Gordon,et al.  Radiance reflected from the ocean-atmosphere system: synthesis from individual components of the aerosol size distribution. , 1994, Applied optics.

[10]  Didier Tanré,et al.  Second Simulation of the Satellite Signal in the Solar Spectrum, 6S: an overview , 1997, IEEE Trans. Geosci. Remote. Sens..

[11]  James W. Brown,et al.  A semianalytic radiance model of ocean color , 1988 .

[12]  K. Stamnes,et al.  Numerically stable algorithm for discrete-ordinate-method radiative transfer in multiple scattering and emitting layered media. , 1988, Applied optics.

[13]  K. Masuda,et al.  Degree of radiance and polarization of the upwelling radiation from an atmosphere-ocean system. , 1985, Applied optics.

[14]  S. Schwartz.  The whitehouse effect—Shortwave radiative forcing of climate by anthropogenic aerosols: an overview , 1996 .

[15]  D. R. Jensen,et al.  The relationship between marine aerosol particles and satellite‐detected radiance , 1986 .

[16]  C. Cox.  Statistics of the sea surface derived from sun glitter , 1954 .