Rosette used to collect seawater samples during a scientific cruise in the South Pacific Ocean. During the austral summer, the amount of chlorophyll a is so low that the water becomes deep blue, almost purple. (Photo : Joséphine Ras)

Deployment of a profiling float (Photo : Jean-Jacques Pangrazi)

Gelatinous plankton Pelagia and Ctenophores  (Photo : Fabien Lombard)

Siphonophores Forskalia formosa (Photo : Fabien Lombard)

Siphonophore  (Photo : Fabien Lombard)

Vue sous-marine d'un groupe de mésocosmes montrant la structure de flottaison en surface (© Stareso)

Profiling float (Photo : David Luquet)

Large rosette sampler used in the "World Ocean Circulation Experiment". This rosette has 36 10-liter Niskin bottles, an acoustic pinger (lower left), an "LADCP" current profiler (yellow long tube at the center), a CTD (horizontal instrument at the bottom), and transmissometer (yellow short tube at the center). (Photo : L. Talley)

Jellyfish Aequorea aequorea  (Photo : Fabien Lombard)

Ctenaria Beroe ovata  (Photo : Fabien Lombard)

Instrumented buoy (Photo : David Luquet)

Dinoflagellate Ceratium ranipes grd mains (Photo : Sophie Marro)

Phytoplankton bloom observed in the Barents Sea (North of Norway) in August 2010 by the ocean color sensor MODIS onboard NASA satellite Aqua. Changes in ocean color result from modifications in the phytoplankton composition and concentration. The green colors are likely associated with the presence of diatoms. The shades of light blue result from the occurrence of coccolithophores, phytoplankton organisms that strongly reflect light due to their chalky shells - Source : NASA's Earth Observatory (http:/earthobservatory.nasa.gov)

Instrumented buoy (Photo : Emilie Diamond)

Foraminifera Ruber (Photo : Fabien Lombard)

Scientists collecting seawater samples from the rosette (Photo : Stacy Knapp, Woods Hole Oceanographic Institution)

Deployment of a profiling float (Photo : Jean-Jacques Pangrazi)