If you see a yellow submarine in the waters of Lake Superior, don’t be surprised. You really aren’t “seeing things.”
The submarine you might be seeing is unmanned and actually a “glider” being used to carry out research beneath the waters of Lake Superior. The University of Minnesota at Duluth, the Large Lakes Observatory and the U.S. Environmental Protection Agency are some of the organizations cooperating on this effort which utilizes National Science Foundation funding. The glider collects data deep within the lake at locations that would otherwise be totally inaccessible.
The glider utilizes changes in buoyancy resulting in forward motion in up and down arcs through the water column. Use of onboard battery power is minimal. Various glider models can remain in motion in Superior for from 25 to 100 days. The glider is given GPS coordinates telling it points to visit and the eventual point of retrieval.
Tom Hollenhorst of U.S. EPA in Duluth says use of the glider is part of the Binational Partnership (federal, provincial and state agencies cooperating to restore and protect Lake Superior) Coordinated Science and Monitoring Initiative (CSMI). This initiative entails a year of more intensive environmental monitoring carried out on a rotating, annual basis in each of the Great Lakes, including Superior.