Average chlorophyll concentration in the surface ocean (from mi-September 1997 to August 2007) from the ocean color sensor SeaWiFS (NASA). Subtropical gyres, in the center of the oceanic basins, are characterized by very low concentrations of chlorophyll a (dark blue) - Source : NASA's Earth Observatory (http:/earthobservatory.nasa.gov)
Surface chlorophyll a concentration in the Mediterranean Sea.
Instrumented buoy (Photo : David Luquet)
Instrumented buoy (Photo : David Luquet)
Dinoflagellate Ceratium gravidum (Photo : Sophie Marro)
Siphonophores - The longest animals on the planet Cousins of corals, siphonophores are colonies of specialized individuals called zoids. Some catch and digest their prey, others swim, or lay eggs or sperm.