Survey of Sea Surface Temperature of the Tsushima Warm Current with Seaborne and Airborne Radiation Thermometers (GARP-Severe Rainstorm Research Project)

Abstract
The horizontal distribution of sea surface temperature was surveyed with a radiation thermometer on the survey ship “Ryofu Maru” in the sea area covering 31°N-31°40'N and 126°40'E-130°E to the west of Kyushu. The surface temperature gradients in the east-west direction at the fronts of the Tsushima Warm Current and scales of water masses as revealed by the continuous records are discussed. A comparison between the skin temperature at the sea surface measured by the radiation thermometer and the temperature of the upper mixed layer of the sea measured by a resistance thermometer indicates that there is no significant difference between them.A preliminary surface temperature measurement with an airborne radiation thermometer was made before the cruise of the “Ryofu Maru.” The decrease of the indicated surface temperature with altitude due to the imperfect transparency of the atmosphere was found to be 2.0° C/km. As to the data obtained at the lower flight level (600m), agreement with the sea surface temperature measured on ships is found to be satisfactory.