Dr. Rossby developed oceanographic instruments, called floats, that drift with the ocean currents, thus tracking water circulation patterns. Dr. Rossby's research team is currently studying the North Atlantic Current to determine its structure vertically and horizontally, and how water is exchanged between warm and cold areas. He and his team have deployed 100 RAFOS floats for 10 months each to study the different water layers and temperatures along the paths of the floats. The paths of the floats, and therefore the general circulation patterns, can be created from the data that is collected.
Dr. Rossby's team is also studying how water flows across the Mid-Atlantic Ridge. This research is part of the Atlantic Climate Change Experiment (ACCE). The image below shows the path of one float as it moves through the Irminger Sea south of Greenland and southwest of Iceland. The path of the float is color-coded to indicate two distinct periods. The red points indicate the location of the float when it was in a mixed layer during the winter. The green points indicate the location of the float when it was in a water body with little oxygen, typically of a highly productive region.