Summer and Winter Structures of Heat Island in Fukuoka Metropolitan Area(<Special Issue>Urban Air and Environment Control Technologies)

The heat island structures of the Fukuoka metropolitan area have been investigated through the observations of temperature in winter and summer from Dec. 26, 2003 to Sep. 14, 2004. In the daytime of both seasons, the Fukuoka metropolitan area is heated almost uniformly over the whole area. Typical heat island structures are formed in the nighttime of both seasons. In the nighttime in summer, the highest temperature is observed at the center of the Fukuoka metropolitan area. Therefore, a concentric and closed pattern of isothermal lines is formed. In the nighttime in winter, the temperature decreases monotonically towards the rural area from the coastline. Therefore, the isothermal lines take on a v-shaped profile. The heat island intensities in both seasons become the highest in the nighttime.