Assessment of global ocean colour products against in-situ datasetsFunded under: FP7-JRC
Ocean colour from satellite has given over the last two decades another dimension to ecosystem studies and marine biology, providing key information on the timing and spatial distribution of phytoplankton blooms, and the magnitude of primary production. Remote observations of ocean colour from space represent therefore a major tool directly related to the marine biogeochemical distributions and associated processes. Presently, the ocean colour community relies on a number of individual missions launched by various space agencies, and the differences resulting from this variety of missions need to be addressed in order to create consistent long term data records. One of the goals of the European GMES Integrated Project MERSEA is to provide an accurate and consistent stream of ocean colour data. In this study we present an extensive comparative analysis of standard ocean colour products obtained from the latest operational global ocean colour sensors (SeaWiFS, MODIS-Aqua, MERIS, GLI, POLDER-2, OCTS and POLDER-1), on both global and regional scales. We analysed and compared monthly mean chlorophyll-a sea surface concentration (Chla) and normalized water leaving radiance (nLW) between July 2002 and June 2005. For Chla on a global scale, SeaWiFS yields the highest geometric mean value whilst MERIS has the lowest values with percentage root mean square differences (Delta) between the two sensors in the order of 17% and a negligible percentage bias (beta). MODIS-Aqua and SeaWiFS are in better agreement with an average global Delta of approximately 13% and with an average beta of +6% with SeaWiFS higher than MODIS-Aqua. On a regional scale, the analysis undertaken on Longhurst's biogeographical provinces show a rather close agreement between SeaWiFS and MODIS-Aqua Chla, with SeaWiFS slightly higher, and larger differences between these products and MERIS Chla.
Bibliographic Reference: EUR 23357 EN (2008), 44 pp. Free of charge
Availability: http://bookshop.europa.eu/is-bin/INTERSHOP.enfinity/WFS/EU-Bookshop-Site/en_GB/-/EUR/ViewPublication-Start?PublicationKey=LBNA23357 (Catalogue Number: LB-NA-23357-EN-C)
Record Number: 200910067 / Last updated on: 2008-11-20
Original language: en
Available languages: en