Remote Sensing of Coastal Waters

Abstract

The coastal areas outside Lofoten, Vesterålen and Senja, in the northern Norwegian coast, are known for their incredible nature, majestic mountains and unique fishing communities. This coastal area is known for high marine productivity and an important marine environment, being the home for valuable fish stocks including pollock, haddock, herring and cod. To study the characteristics of coastal waters, remote sensing techniques are useful tools. Level 2 ocean color images, containing water quality parameters, and sea surface temperature(SST) images are collected from the optical satellite Sentinel-3, as well as intensity images and geophysical Doppler images from the Synthetic Aperture Radar(SAR) satellite Sentinel-1 are collected. When observing ocean color water quality parameters such as chlorophyll(CHL), total suspended material(TSM) and colored dissolved organic material(CDOM), and SST images, we can observe patterns that appear to be generated by ocean dynamics. The SAR intensity is modified by wind stress and currents variations, and the geophysical Doppler can tell us something about the velocity field in the line of sight direction of the satellite. This study has investigated the relations between ocean color parameters, the SST and the SAR intensity and geophysical Doppler. Using statistical analysis approaches, the results show a clear relation between the various ocean color parameters, a less significant relation between ocean color parameters and SST, but no clear correlation between CHL or SST and the SAR products. The optical and near infrared radiation used to estimate ocean color and SST parameters is dependent on light and nice weather, while the microwave radiation that is used in the SAR products is not. Our investigations do not establish a significantly clear relation between CHL, SST and the SAR products to maintain that SAR images can complement optical sensors in understanding coastal waters during periods with less light and bad weather conditions.