The measurement of sea surface temperature with an infrared radiometer

The purpose of this experiment was to make simultaneous measurements of sea surface temperature with infrared and microwave radiometers. Such measurements should be useful for determining the accuracy of satellite radiometer measurements of sea surface temperatures. Measurements were made with RCA personnel as part of PROJECT ROCKFISH, at a test site on the Chesapeake Bay Bridge Tunnel near Norfolk, Virginia. Microwave and infrared radiometer measurements of the sky and water temperatures were made at various angles from the zenith down to the shoreline, at a nadir angle of55\deg. A mercury thermometer and a network of floating thermistor beads were used to make simultaneous independent measurements of the water temperature. Analysis of the infrared radiometric data from Chesapeake Bay showed that for incidence or viewing angles of60\degor less, the data could be corrected to within\pm 1\degC of the thermometer and thermistor data, by assuming specular reflectance at the sea surface for sky background radiation.