A study of the applications of airborne infrared equipment for detecting water masses and currents of the Great Lakes is described. Infrared scanners were used to make thermal strip maps and an infrared radiometer was used to obtain surface temperatures of the western end of Lake Erie and the lower Detroit River. Simultaneously, surface water temperatures were taken and water samples were collected for chloride determinations from four vessels making a 4 day synoptic survey of the test area. The remote infrared measurements are compared with shipboard temperature data to evaluate their usefulness in demonstrating thermal structure, water masses, and currents in the test area.