In this study, we analyzed the relationship between land cover and air temperature in the urban area of Hiroshima during calm period, sea breeze period, and land breeze period in the summer. The summary of the results is shown below. 1) It is clear that the wind is the most influential factor for the city temperature, and the influential range of land cover reaches a maximum of about 250m. 2) In the land and sea breeze period, the river and open areas becomes a ventilation path that lowers the city temperature with a cold wind. 3) In the morning time, during the calm period, the green zone lowers the city temperature, and the open area raises the city temperature by solar radiation. At the night time, during the calm period, the high buildings raises the city temperature.
