Keeping an Eye on Earth’s Oceans With Argo Floats

A new book written by oceanographers explores how scientists conduct research below the surface of the ocean. There are several types of robots that can dive below the sea surface and bring back data from underwater. One type of robot, called an Argo float, moves through the middle depths of the ocean with the currents and comes to the surface once every 10 days, to tell scientists about the information that it has collected. Even though we call these robots “floats,” they actually go up and down in the ocean from the surface to 1,000 m deep and move freely with the ocean currents at that depth for 9 days. On day 10, they dive to down 2,000 m, then rise to the surface, taking ocean measurements on their way up. When they reach the surface, they send the collected data and their location back to scientists via satellites.  The cycle of diving to 1,000m, drifting for 9 days, diving to 2,000m, and collecting data on the way to the surface occurs every 10 days for five years (or the lifespan of a float), thus enabling scientists to build a database of information about the ocean.