Abstract
　A remote sensing of high temperatures on the slope of Mt. Unzen-Fugendake Volcano was made by infrared thermometer. The maximum surface temperature on the northeast slope (Dome 4) of 18 October 1991 was 190℃ and the surface area of raised temperature (>50℃) was 149,000m2. The surface area of raised temperature on 3 April 1992 was greater than that on 18 October 1991. The changes in maximum surface temperature on the northeast slope and the east slope (Dome 2) followed. The maximum surface temperature of a pyroclastic flow of Dome 2 measured on 4 December 1991 was 236℃. The decreasing rate of surface temperature of a pyroclastic flow was 2.4− 3.9℃/min.

【キーワード】：雲仙・普賢岳，赤外放射温度計，表面温度，リモートセンシング
Key words: Mt. Unzen-Fugendake volcano, infrared thermometer, remote sensing, surface temperature

*九州農業試験場生産環境部
Department of Agro-Environmental Management, Kyushu National Agricultural Experiment Station
**九州大学農学部
Faculty of Agriculture, Kyushu University
***山口大学農学部
Faculty of Agriculture, Yamaguchi University