A potentially universal algorithm for estimating aerosol scattering reflectance from satellite remote sensing data

Abstract Accuracy of aerosol scattering reflectance in atmospheric correction is crucial for satellite ocean color remote sensing. A new approach is developed to estimate aerosol scattering reflectance from satellite data based on a look-up table of in situ water-leaving reflectance. A decision rule is set to determine the water-leaving component of the total satellite-measured radiance from the table under an assumption that aerosol scattering reflectance follows the Angstrom law. The epsilon spectrum, obtained from the ratio of aerosol scattering reflectance, is used to select the two closest aerosol models for determining the corrected epsilon values, which is adjusted to new values according to the reference wavelength. The actual aerosol scattering reflectance is obtained from the mean value of the reflectance and the new epsilon spectrum. The performance of the model is evaluated using the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) imagery, showing that the component of aerosol scattering reflectance can be completely separated from the total satellite-measured radiance, and effects of non-zero water-leaving reflectance can be eliminated over highly turbid waters. The accuracy is validated by in situ measured aerosol optical thickness (AOT) using a handheld multi-band sun photometer and the Aerosol Robotic Network (AERONET) measured AOT data during the 2006 winter cruise and 2007 autumn cruise over the East China Sea (ECS). The analysis gives the mean relative errors of 23.73% and 32.04%, respectively. Our analysis shows that aerosol scattering reflectance can be significantly overestimated over turbid waters when using the atmospheric correction method based on the black ocean assumption (BOA). It may also have some errors over oceanic waters because a small 1% bias of satellite-measured reflectance in the near-infrared (NIR) bands will lead to a relatively large error of ~ 10% in aerosol scattering reflectance in Band 1. This error will spread to water-leaving reflectance, possibly leading to negative values of water-leaving reflectance. This amplifying effect of aerosol scattering reflectance can be limited by matching aerosol models using epsilon spectrum in our model. Because the assumption of aerosol scattering reflectance following the Angstrom law can eliminate effects of different types of waters including open ocean, coastal regions, lakes and rivers, our model offers a potentially universal algorithm for estimating aerosol scattering reflectance from satellite remote sensing data.

[1]  C. Chen,et al.  Using geostationary satellite ocean color data to map the diurnal dynamics of suspended particulate matter in coastal waters , 2013 .

[2]  Delu Pan,et al.  A regional remote sensing algorithm for total suspended matter in the East China Sea , 2012 .

[3]  Menghua Wang,et al.  Retrieval of water-leaving radiance and aerosol optical thickness over the oceans with SeaWiFS: a preliminary algorithm. , 1994, Applied optics.

[4]  Y. Ahn,et al.  New atmospheric correction technique to retrieve the ocean colour from SeaWiFS imagery in complex coastal waters , 2007 .

[5]  Menghua Wang.  Remote sensing of the ocean contributions from ultraviolet to near-infrared using the shortwave infrared bands: simulations. , 2007, Applied optics.

[6]  J. W. Brown,et al.  Exact Rayleigh scattering calculations for use with the Nimbus-7 Coastal Zone Color Scanner. , 1988, Applied optics.

[7]  H. Gordon,et al.  Removal of atmospheric effects from satellite imagery of the oceans. , 1978, Applied optics.

[8]  Robert Frouin,et al.  In-orbit calibration of SeaWiFS in the near infrared , 2004, SPIE Remote Sensing.

[9]  M. Wang,et al.  Validation study of the SeaWiFS oxygen A-band absorption correction: comparing the retrieved cloud optical thicknesses from SeaWiFS measurements. , 1999, Applied optics.

[10]  H. Gordon,et al.  Aerosol analysis with the Coastal Zone Color Scanner: a simple method for including multiple scattering effects. , 1989, Applied optics.

[11]  H. Gordon,et al.  Surface-roughness considerations for atmospheric correction of ocean color sensors. II: Error in the retrieved water-leaving radiance. , 1992, Applied optics.

[12]  Menghua Wang,et al.  A simple, moderately accurate, atmospheric correction algorithm for SeaWiFS☆ , 1994 .

[13]  J. Haigh,et al.  Atmospheric correction over case 2 waters with an iterative fitting algorithm. , 1996, Applied optics.

[14]  J. Ryu,et al.  Development of atmospheric correction algorithm for Geostationary Ocean Color Imager (GOCI) , 2012, Ocean Science Journal.

[15]  Menghua Wang,et al.  Effects of ocean surface reflectance variation with solar elevation on normalized water-leaving radiance. , 2006, Applied optics.

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

[17]  Zengzhou Hao,et al.  A new approach to estimate the aerosol scattering ratios for the atmospheric correction of satellite remote sensing data in coastal regions , 2013 .

[18]  Menghua Wang.  Aerosol polarization effects on atmospheric correction and aerosol retrievals in ocean color remote sensing. , 2006, Applied optics.

[19]  K. Ruddick,et al.  Atmospheric correction of SeaWiFS imagery for turbid coastal and inland waters. , 2000, Applied optics.

[20]  Alexander Smirnov,et al.  Validation of SeaWiFS and MODIS aerosol products with globally distributed AERONET data , 2010 .

[21]  Menghua Wang,et al.  Estimation of ocean contribution at the MODIS near‐infrared wavelengths along the east coast of the U.S.: Two case studies , 2005 .

[22]  S. Maritorena,et al.  Atmospheric correction of satellite ocean color imagery: the black pixel assumption. , 2000, Applied optics.

[23]  Delu Pan,et al.  THE ATMOSPHERIC CORRECTION ALGORITHM OF SeaWiFS DATA IN CHINA SEAS , 2001 .

[24]  Bryan A. Franz,et al.  On-orbit calibration of SeaWiFS. , 2012, Applied optics.

[25]  H. Gordon,et al.  Analysis of the influence of O(2) A-band absorption on atmospheric correction of ocean-color imagery. , 1995, Applied optics.

[26]  F. Muller‐Karger,et al.  Atmospheric Correction of SeaWiFS Imagery over Turbid Coastal Waters: A Practical Method , 2000 .

[27]  Robert A Barnes,et al.  Reflectance-based calibration of SeaWiFS. I. Calibration coefficients. , 2003, Applied optics.

[28]  H. Gordon,et al.  Coastal Zone Color Scanner atmospheric correction algorithm: multiple scattering effects. , 1987, Applied optics.