Phytoplankton Bloom Dynamics in Greenland Sea Using Ocean Color Remote Sensing

Abstract:

The purpose of this study is to understand phytoplankton bloom dynamics in Greenland Sea using ocean color satellite remote sensing. Greenland Sea is a section of the southern Arctic Ocean off the eastern coast of Greenland, and just a small part of global ocean. However, a recent study revealed that Greenland Sea has warmed 10 times faster than global ocean on average and can be a leading indicator of climate change. Interannual and seasonal variability of chlorophyll a concentration in the Greenland Sea can be identified spatially by ocean color remote sensing. For extrapolation of bloom of past years, MODIS (Moderate Resolution Imaging Spectroradiometer), SeaWiFS (Sea-viewing Wide Field-of-view Sensor) and CZCS (Coastal Zone Color Sensor) 8-day chlorophyll a data were fitted to Gussian function of time (Yamada et al., 2006). Parameters obtained from the Gaussian fit are start timing, end timing of the bloom, peak concentration, peak timing and bloom duration. The bloom timing and its magnitude were spatially varying. Satellite data indicate that the blooms of northward of Jan Mayen were the largest and most intense, with chlorophyll a concentration often exceeding 10 mg m^-3. The bloom started at the west coast of Spitsbergen in May, northward of Jan Mayen in June and continued through June and July, respectively. The bloom in the Greenland Sea in 2004 appeard one month earlier than others and was the largest in 2007. We also investigated sea ice concentration percent observed by SSM/I (Special Sensor Microwave Imager) and SSMIS (Special Sensor Microwave Image Sounder) satellite sensors for the same period. The results show that bloom timing seemed to be related with the anomalous variations of sea ice extent in northern Greenland Sea, ocean currents and variability of global climate index.