Variability of particulate organic carbon concentration in the north polar Atlantic based on ocean color observations with Sea-viewing Wide Field-of-view Sensor (SeaWiFS)

[1] We use satellite data from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) to investigate distributions of particulate organic carbon (POC) concentration in surface waters of the north polar Atlantic Ocean during the spring - summer season ( April through August) over a 6-year period from 1998 through 2003. By use of field data collected at sea, we developed regional relationships for the purpose of estimating POC from remote-sensing observations of ocean color. Analysis of several approaches used in the POC algorithm development and match-up analysis of coincident in situ - derived and satellite-derived estimates of POC resulted in selection of an algorithm that is based on the blue-to-green ratio of remote-sensing reflectance R-rs ( or normalized water-leaving radiance L-wn). The application of the selected algorithm to a 6-year record of SeaWiFS monthly composite data of L-wn revealed patterns of seasonal and interannual variability of POC in the study region. For example, the results show a clear increase of POC throughout the season. The lowest values, generally less than 200 mg m(-3), and at some locations often less than 50 mg m(-3), were observed in April. In May and June, POC can exceed 300 or even 400 mg m(-3) in some parts of the study region. Patterns of interannual variability are intricate, as they depend on the geographic location within the study region and particular time of year ( month) considered. By comparing the results averaged over the entire study region and the entire season ( April through August) for each year separately, we found that the lowest POC occurred in 2001 and the highest POC occurred in 2002 and 1999.