Ocean Colour Remote Sensing in Polar Seas.

Abstract

Accelerating climate change calls for a vastly improved understanding of the polar ecosystems based on an intensive observation program. In situ observations from ships are, however, inherently sparse in space and time, especially in the harsh and inaccessible Arctic Ocean. Ocean colour remote sensing offers one of the most appropriate tools to extensively monitor marine ecosystems, as it can provide recurrent pan-Arctic and pan-Antarctic observations at relatively low cost. The use of ocean colour remote sensing in Polar Regions is impeded by a number of intrinsic limitations including the persistence of cloud and fog, prevailing low solar elevations, the impact of ice on remotely-sensed reflectance and the optical complexity of seawater, especially over the Arctic shelves. This report sheds light on the impact of the unusual conditions found in polar regions on ocean colour products. Current ocean colour algorithms are tested using a compiled dataset of in situ observations of optical properties in polar seas. Recommendations are made and new approaches and concepts for studying the polar regions using ocean colour remote sensing are proposed.