Validation of Meris Geophysical Products in Open Ocean and Coastal Waters in the Southern North Sea and Western English Channel

The absorption coefficient of phytoplankton, detrital material and coloured dissolved organic material and Chl a concentrations were collected during cruises in 2002 & 2003 under the framework of the European Research Contract The Regional Validation of MERIS chlorophyll products in North Sea coastal waters (REVAMP, EVG1-CT-200100049). Three campaigns were undertaken in coastal regions of the North Sea, four campaigns were conducted in open ocean waters of the Celtic Sea and a bi-weekly time series was collected off Plymouth Sound in the Western English Channel. A total of 27 coincident MERIS images were identified over 246 stations. This paper quantifies the differences between in-situ measurements of the absorption coefficient of yellow substance (YS), chlorophyll a (Chl a) and Total suspended material (TSM) and the corresponding Level 2 geophysical products derived from coincident MERIS images. The results show that Chl a was underestimated by a 20%, YSBPA was underestimated by 42% and TSM was overestimated by a 16%. These errors fall within the specifications of MERIS products.