Thousands of buoys and floats worldwide are equipped with Argos transmitters, sending regular information via the Argos system to help scientists understand and predict climate change. Nearly 6,000 drifting buoys, deep floats, moored buoys and fixed stations fitted with Argos transmitters measure ocean currents and send millions of measurements including atmospheric pressure, wind speed and direction, sea temperature and more to follow climate evolution. These Argos transmitters are important components of the World Climate Research Program (WCRP) programs, through TOGA, WOCE and now GOOS/GCOS, CLIVAR and GODAE programs and experiments.