Abstract
Measurements of temperature at points ranging from 10 cm above the water surface to 6 cm below it were undertaken by the use of thermocouples at the water pool installed outside the Meteorological Research Institute. At the same time, the water surface temperature was measured by the radiometer (7.5-11.5 μm) to compare it with the water temperature measured by the thermo-couples. Then the radiometer was scanned along the nadir angle of observations ranging from 30° to 80° under various weather conditions. A comparison of water surface temperature thus measured with that derived theoretically tells that at large nadir angles of observations, the temperature deviation from the calculated ones is large. This may be due to the surrounding conditions, particularly the existence of cloud. Furthermore, the temperature below the water surface is different from that measured by the radiometer. Hence to discuss the accuracy of the sea surface temperature measured by satellites, it is essential to obtain radiometric sea surface temperature by ships.
