<title>Atmospheric and sea state dependence of polarized infrared contrast</title>

Abstract

Sea radiance in the mid and far infrared shows a considerable degree of polarization which affects observed target-to-background contrast. An improvement in contrast is achieved with horizontal (s-plane) polarization filtering to suppress sea surface emission. Visibility and range affect the contrast in both polarizations. Scenes recorded during the MAPTIP measurement series off the coast of the Netherlands with the oceanographic ship HrMs Tydeman show decrease in contrast with range and better contrast for horizontal polarization against sea background. A simple mathematical model is presented relating contrast to extinction and path radiance which increase with increasing path length or worsening visibility.