Ocean Colour remote sensing in the Southern Laptev Sea: evaluation and applications

• Published in: Biogeosciences
• Main Authors: Heim, B., Abramova, E., Doerffer, R., Günther, F., Hölemann, Jens A., Kraberg, A., Lantuit, H., Loginova, Alexandra, Martynov, F., Overduin, P. P., Wegner, Carolyn
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications (EGU) 2014
• Subjects: Arctic; Laptev Sea; Ice; laptev; permafrost
• Online Access: https://oceanrep.geomar.de/id/eprint/24691/; https://oceanrep.geomar.de/id/eprint/24691/1/bg-11-4191-2014.pdf; https://doi.org/10.5194/bg-11-4191-2014

Enhanced permafrost warming and increased arctic river discharges have heightened concern about the input of terrigeneous matter into Arctic coastal waters. We used optical operational satellite data from the Ocean Colour sensor MERIS onboard the ENVISAT satellite mission for synoptic monitoring of the pathways of terrigeneous matter in the southern Laptev Sea. MERIS satellite data from 2006 on to 2011 were processed using the Case2Regional Processor, C2R, installed in the open-source software ESA BEAM-VISAT. Since optical remote sensing using Ocean Colour satellite data has seen little application in Siberian Arctic coastal and shelf waters, we assess the applicability of the calculated MERIS parameters with surface water sampling data from the Russian-German ship expeditions LENA2010 and TRANSDRIFT-XVII taking place in August and September 2010 in the southern Laptev Sea. The surface waters of the southern Laptev Sea are characterized by low transparencies, due to turbid river water input, terrestrial input by coastal erosion, resuspension events and, therefore, high background concentrations of Suspended Particulate Matter, SPM, and coloured Dissolved Organic Matter, cDOM. The mapped calculated optical water parameters, such as the first attenuation depth, Z90, the attenuation coefficient, k, and Suspended Particulate Matter, SPM, visualize resuspension events that occur in shallow coastal and shelf waters indicating vertical mixing events. The mapped optical water parameters also visualize that the hydrography of the Laptev Sea is dominated by frontal meanders with amplitudes up to 30 km and eddies and filaments with diameters up to 100 km that prevail throughout the ice-free season. The meander crests, filaments and eddy-like structures that become visible through the mapped MERIS C2R parameters indicate enhanced vertical and horizontal transport energy for the transport of terrigenous and living biological matter in the surface waters during the ice-free season.