Effect of storms on the suspended matter concentration in the Bay of Biscay

This situation occured in mid January 1998 : it is a typical winter situation where winds spreads suspended matters over large areas (areas in white are cloudy and could not be observed by satellite). It also emphasize the need in ocean color algorithm to clearly discriminate inorganic suspended matters from chlorophyll.

 

suspended-matter-10-Jan-1998Suspended matter by SeaWifs (Ifremer algorithm) on 10th January 1998. Following strong westerly winds in the beginning of Januray, sous-eastern winds spread suspended matters over a very large area. chlorophyll-a-10-Jan-1998Chlorophyll-a by SeaWifs (Ifremer algorithm) on 10th January 1998. By application of a local algorithm to the SeaWiFS reflectance, the signature of the suspended matter has been separated from that of the chlorophyll which is negligible at that period of the year. This task is essential in coastal waters where both signatures are mixed. Application of a standard algorithm defined for clear oceanic waters (as OC4) would lead to a dramatic overestimation of the chlorophyll concentration.

 

 

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