A new climatology for atmospheric correction based on the aerosol inherent optical properties

Abstract

In the aerosol remote sensing algorithms over ocean, the aerosol models are deduced from the spectral dependence of the path radiances in the near‐infrared region. In the classical scheme of atmospheric corrections, the key point is the derivation of atmospheric signals in the visible part of the solar spectrum using these aerosol models. The aerosol climatology generally includes the standard aerosol models. Nevertheless, the latter may not be representative enough of the variety of aerosols encountered over coastal areas. One way to extend this climatology is to generate additional aerosol models. The latters will be described by their micro‐physical properties and their inherent optical properties (IOPs) can then be computed with the Mie 's theory. Coastal and inland stations of CIMEL sun‐photometers from the AERONET (AErosol RObotic NETwork) offer an extensive and representative data set of aerosol characteristics (i.e., the apparent optical properties from which can be derived the IOPs) in the marine environment through solar extinction and sky radiance measurements. An iterative method, developed at the ≪ Laboratoire Interdisciplinaire des Sciences de l ' Environnement ≫ (LISE, Wimereux‐France), allows to extract the aerosol phase function from these ground‐based measurements. CIMEL data, collected over 25 stations during several years, were processed to build‐up a database with more than 7000 sequences including single scattering albedos and phase functions at two wavelengths (675 nm and 870 nm). Statistical methods have been applied on this data set to discard the wrong sequences and to suggest a classification in aerosol models through their IOPs.