Observation of Sea Surface Temperature by an Infrared Radiation Thermometer

Abstract

Laboratory experiments were made to examine some characteristics of a radiation thermometer (PRT 14-313, Barnes Engineering Company). Effect of nonblackness of the water surface and a large temperature difference between the water and the air above it were investigated.
Sea surface temperatures were then measured by the radiation thermometer, thermistor thermometers and a mercury thermometer from a marine tower. The result showed that the temperature at the air-sea interface was not always cooler. than the subsurface temperature. The standard deviation of difference of temperatures measured by the radiation thermometer and the thermistor thermometer was 0.44°C. The dependence of the temperature difference on various factors was investigated with the result that current velocity had a good correlation with the temperature difference.