The first MERIS observation captured the huge phytoplankton patch produced by the 'upwelling' mechanism along the west coast of Africa near Mauritania. The unprecedented resolution allows fine-scale structures to be detected. In such upwelling areas, northeast trade winds bring deep and nutrient-rich water to the surface, feeding phytoplankton. Changes in climate affect the intensity of the upwelling with important consequences for marine ecosystems, fisheries and local economies.

One important task for MERIS is to provide overviews of the dynamics of upwelling areas and their primary production. This, in turn, could improve management of fish stocks within sustainable limits. Another important task for MERIS is to provide information on carbon fixation through photosynthesis within the global ocean for a better understanding of the carbon cycle.

Technical Information:
Instrument: MEdium Resolution Imaging Spectrometer (MERIS)
Date of Acquisition: 22 March 2002
Orbit number: 00306
Instrument features: Full resolution image (300-meter resolution)
MERIS was designed to measure the concentration of phytoplankton. The colours seen by MERIS indicate the concentration of chlorophyll, the pigment that phytoplankton use for photosynthesis. MERIS can detect chlorophyll concentrations as low as 0.01 microgram, or 1/100 000 000 of a gram, per litre. MERIS data will be used to monitor the worldwide distribution of phytoplankton and to compute primary production.