A numerical study of microwave emission from ocean foam layer

Abstract

This paper presents a numerical study of microwave brightness temperature of residual foam cover on ocean surface. The foam layer is modeled using Kelvin's Tetrakaidecahedron structure. Absorption and scattering of the foam layer, i.e. the layer phase matrix, are calculated using a multilevel UV method to accelerate method of moment (MoM) solution of Maxwell's equations. Matrix doubling method, which accounts for interactions between the foam volume and interfaces, is then utilized to determine the total emission from the foam layer. The calculated foam layer absorption rates at a frequency range of 1.5GHz to 36.5GHz are presented and analyzed for both H and V polarizations. Brightness temperatures at 1.5GHz for both planar and rough interface with different water fractions in the foam layer are simulated and analyzed. Effects of foamboundary interactions on foam layer emission are discussed.