高知市の接地逆転とヒートアイランド

抄録

Moving observations were conducted to detect the changes in the night temperature distribution over the last 20 years, and to confirm the relationship between the inversion layer and the heat island intensity in Kochi, Japan. The results obtained in this study are as follows: (1) Comparing the night temperature distribution from 1998 to 1999 with that of 8 years and 20 years ago, the warm area which appears in the central part of the city tends to have reduced its area. (2) Results of the observations of the inversion layer along Kosaka Pass, temperature is the warmest between 170 meters and 200 meters above sea level. The inversion layer may exist below this level regardless of the season. (3) The intensity of the inversion layer (the temperature gradient for every 100 m) is the highest in winter, and the maximum inversion intensity is 2.6℃. As the temperature becomes warmer, the inversion tends to weaken, and in summer the inversion layer sometimes does not exist. (4) The intensity of the heat island is the highest in winter, and the maximum heat island intensity is 3.9℃. This value is about 1℃ lower than Nagano City and Toyohashi City which have the same population as Kochi City. In summer, the heat island sometimes exists without the inversion layer.