OCOC: From Ocean Colour to Organic Carbon
Heim, Birgit1; Abramova, Ekaterina2; Doerffer, Roland3; Guenther, Frank1; Hoelemann, Jens1; Kraberg, Alexandra1; Lantuit, Hugues1; Loginova, Alexandra4; Martynov, Fedor5; Overduin, Paul1; Wegner, Carolyn4
1Alfred Wegener Institute for Polar and Marine Research, GERMANY; 2Lena Tiksi Reservate, RUSSIAN FEDERATION; 3HZG Helmholtz Research Centre Geesthacht, GERMANY; 4GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, GERMANY; 5St. Petersburg University, St. Petersburg, GERMANY
The 'OCoc-from Ocean Colour to Organic Carbon' project (IPY-project 1176), funded by the German Research Foundation (DFG), is an Ocean Colour study joined with the Arctic Coastal Dynamics ACD network and Arctic Circum-polar Coastal Observatory Network ACCO-Net (IPY-project 90). 'ocOC- from Ocean Colour to Organic Carbon' (2008-2010) uses Ocean Colour (OC) data to investigate the pathways of terrestrial Organic Matter in the Laptev Sea, Arctic Siberia.
The Laptev Sea Region has become an ESA COASTCOLOUR investigation site to use insitu data from Russian-German ship expeditions. The multi-year expedition data are the base for understanding the optico-chemico properties of the coastal waters that are characterized by low transparencies, resuspension events and high cDOM concentrations.
Ocean Colour MERIS satellite data were processed using Beam-Visat4.2 and the MERIS case2 regional processor for coastal application (C2R). Initial comparisons show that the Siberian Arctic coastal waters cannot be treated with standard remote sensing processing. In the Laptev Sea region, the high loads of organic matter from coastal and river sources lead to an overestimation in all chlorophyll remote sensing products (NASA SeaWifs, NASA MODIS, ESA MERIS). The standard NASA and ESA chlorophyll maps show an overestimation by an order of one magnitude.
the MERIS-C2R optical parameters 'total absorption' and the first attenuation depth, 'Z90', seem adequately to represent true conditions. We can use high attenuation values in the spectral blue wavelength range to trace the terrigenous input. Ocean Colour data show the hydrographic dynamics during the ice-free summer season.