Leeuw, G. de
Eijk, A.M.J. van
TNO Defensie en Veiligheid
|Source:||Doss-Hammel S.M.Kohnle A., Atmospheric Optical Modeling, Measurement, and Simulation, 2-3 August 2005, San Diego, CA, Conference code: 66303, 5891, 1-9|
|Proceedings of SPIE - The International Society for Optical Engineering|
Physics · Aerosol · ANAM · EOSTAR · Satellite retrieval · Atmospheric optics · Coastal zones · Electrooptical devices · Light propagation · Meteorology · Optical sensors · Satellite communication systems · Atmospheric aerosols
The detection of targets at low levels above the sea surface by electro-optical (EO) sensors is affected by the atmosphere. Models have been developed to describe the electro-optical propagation in the marine atmospheric surface layer as a function of meteorological parameters. EOSTAR is an end-to-end model suite for EO sensor performance in which the Advanced Navy Aerosol Model (ANAM) is embedded for computing the aerosol extinction. While ANAM provides favorable results in open ocean conditions where the aerosols predominantly consist of sea salt particles, the model lacks accuracy in coastal zones due to the presence of aerosols from a variety of other sources. In offshore wind conditions continental aerosols of anthropogenic and natural origin mix with marine aerosols produced in the surf zone and by wave breaking further offshore. In principle, ANAM can be extended with the various aerosol types that may occur in the coastal zone, but to correctly handle their effect on EO propagation, information is required on the actual aerosol mixture over the range of interest. In this contribution we explore the potential of satellite instruments to provide this information. Radiometers on satellites can be used to retrieve the spatial variation over an extended area determined by the swath width, with a resolution determined by the radiometer pixel size. Input into this retrieval is a model describing the aerosol mixture in varying ratio, e.g. a mixture of continental and marine aerosol. While the marine component can be constrained by ANAM using local meteorological input parameters, the continental component can be retrieved and used as input to determine the fine particle distribution in ANAM.