The gliders are autonomous underwater vehicles, which collect data by
diving down into the water column and back to the surface as they travel
through the lake to sets of programmed GPS coordinates. While underway,
the gliders are continuously measuring such parameters as water temperature,
backscatter (a metric for the amount of particles in the water),
chlorophyll, and CDOM (colored dissolved organic matter), among other
things. Because the gliders are moving both horizontally and vertically
through the water, they produce cross-sectional images of the lake for
each of these parameters.
While used extensively in the oceans, there are currently only three of these autonomous gliders operating in the Great Lakes, two of which operate out of Duluth. Gichigami is owned and operated by the University of Minnesota Duluth Large Lakes Observatory, with funding from the Great Lakes Observing System (GLOS). Nokomis is owned and operated by the US EPA.