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)

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

Villefranche-sur-Mer in stormy weather, winter 2011 - Photo : J.-M. Grisoni

Jellyfish Aequorea aequorea  (Photo : Fabien Lombard)

Diatom species Odontella mobiliensis (Photo : Sophie Marro)

Jellyfish Pelagia noctilica  (Photo : Fabien Lombard)

Dinoflagellate Ceratium falcatum (Photo : Sophie Marro)

Instrumented buoy (Photo : Emilie Diamond)

Underwater glider (Photo : David Luquet)

Ostracodes  (Photo : Fabien Lombard)

Carte bathymétrique de la Mer Méditerranée

Surface chlorophyll a concentration in the global ocean.

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

Siphonophore  (Photo : Fabien Lombard)

Dinoflagellés Ceratium massiliense var protuberans (Photo : Sophie Marro)

Dinoflagellate Ceratium arietinum var arietinum (Photo : Sophie Marro)