RAFOS Floats

RAFOS floats are designed to take measurements of temperature, salinity, and pressure in layers of ocean water at any depth.They are deployed using one of two methods. Some floats are attached to a small anchor and dropped over the side of a research vessel (left). They sink to the bottom and remain there, in a dormant state, until a preprogrammed time when they release the anchor and rise up to their target depth to start their drifting mission.

After completing their drifting mission, these floats release a second weight and rise to the sea surface, where they transmit all their stored data to orbiting satellites which then rebroadcast the information to ground stations (right).

Most floats however begin their drifting missions immediately after deployment from a research vessel or ship of opportunity (middle). At the end of their drifting mission, they also transmit the data they collected to satellites that relay the information to the scientist.  (Illustration by Jayne Doucette, Woods Hole Oceanographic Institution)