The acoustic tomography approach provides an indirect measure of the temperature of an ocean volume. The technique provides an integrated measure of temperature along the sound propagation paths. The variety of paths between a transmitter and a receiver, as well as the large number of instruments deliver information on the variability of the thermal content of the insonified volume.

X : eXpendable; B : Bathy; T: Thermograph. Thermal profile measurement with real-time transmission

Routine operation over a period shorter than 5 years (Enhanced Observation Period, EOP)

Routine operation over a period shorter than 5 years (Enhanced Observation Period, EOP)

GOSUD aims at assembling in-situ observations of the world ocean surface collected by a variety of ships and at distributing quality controlled datasets. At present time the variables considered by GOSUD are temperature and salinity. The GOSUD data are mostly collected using thermosalinographs (TSG) installed on research vessels, on commercial ships and in some cases on sailing exploration ships. GOSUD manages both near-real time (RT and NRT) data and delayed mode (DM-reprocessed) data. The GOSUD GDAC is hosted by the Coriolis data centre (France) and a back-up (permanent archived) is performed on a daily basis by NCEIS (NOAA's National Centers for Environmental Information).

Raw seismic reflection data archived at SISMER, acquired: - by oceanographic vessels and national equipment managed by the French Oceanographic Fleet (FOF) - by foreign oceanographic vessels in collaboration with Ifremer - by Ifremer's historic vessels (Jean Charcot, Nadir, Suroit) operated before the FOF was set up

Observation of surface currents by HF radars. This system of HF radars makes it possible to compile, continuously and over long periods, maps of surface marine currents, up to 100km and with a spatial resolution of 3km.

Raw underway marine gravity data archived at SISMER, acquired: - by oceanographic vessels and national equipment managed by the French Oceanographic Fleet (FOF) - by foreign oceanographic vessels in collaboration with Ifremer - by Ifremer's historic vessels (Jean Charcot, Nadir, Suroit) operated before the FOF was set up

Raw multibeam from acoustic echosounding of the water column and archived at SISMER. These data have been acquired: - by oceanographic vessels and national equipment managed by the French Oceanographic Fleet (FOF) - by foreign or national oceanographic vessels in collaboration with Ifremer