Slicks as Indicators for Marine Processes

Abstract

Monomolecular surface films ("sea slicks") are well known to dampen small-scale waves at the water surface, thereby influencing transport processes at the air-sea interface. Because of their strong wave-damping capacity, they can often be observed, not just on synthetic aperture radar imagery, but also on imagery acquired in the visible and infrared spectral ranges. Because sea slicks tend to accumulate at the water surface along lines of, for example, current shear in fronts and eddies, they can be used as proxies for observing such marine processes from space. We demonstrate how well sea slicks are suited to indicate marine processes in the coastal zone. A slick's damping capability depends on the surfactant concentration on the sea surface and, thus, on the compression status of the slick-forming material. Furthermore, we show that slick signatures can be used to derive surface current vectors at higher spatial resolution than that of numerical models.

Keywords

• synthetic aperture radar
• SAR
• surface films
• slicks
• surfactant
• wave damping