Effect of the observation length on the two-dimensional shadowing function of the sea surface: application on infrared 3-13-microm emissivity.
An analytical approach of the two-dimensional emissivity of a rough sea surface in the infrared band is presented. The emissivity characterizes the intrinsic radiation of the sea surface. Because the temperature measured by the infrared camera depends on the emissivity, the emissivity is a relevant parameter for retrieving the sea-surface temperature from remotely sensed radiometric measurements, such as from satellites. This theory is developed from the first-order geometrical-optics approximation and is based on recent research. The typical approach assumes that the slope in the upwind direction is greater than the slope in the crosswind direction, involving the use of a one-dimensional shadowing function with the observed surface assumed to be infinite. We introduce the two-dimensional shadowing function and the surface observation length parameters that are included in the modeling of the two-dimensional emissivity.
Bourlier
C
C
Laboratoire Systémes Electronique et Informatiquey/EP, Centre National de la Recherche Scientifique 2081, Ecole Polytechnique de l'Université de Nantes, Institut de Recherche de l'Enseignement Supérieur aux Techniques de l'Electronique, Rue Christian Pauc, La Chantrerie, BP 50609, 44306 Nantes Cedex 3, France. cbourlie@ireste.fr
Saillard
J
J
Berginc
G
G