近年，各地の都市域において都市高温化が発生し，夏季を中心に人々の生活に深刻な悪影響を及ぼしている．さらに今後，人口減少に伴う高齢化によって，都市熱環境の悪化に対して脆弱な社会が形成されていくと考えられる．そのため特に地方都市では人口減少社会への都市構造再編と同時に熱環境悪化に対するリスクを低減する都市のあり方を考えていく必要がある．
　本報ではその第一歩として，広島県福山市全域を対象に気温実測調査を行い，気温分布傾向把握とクラスター分析による測定地点の類型化の結果から高温化・低温化しやすいエリアの抽出を行った。結果として，都市中心部で昼夜ともに高温化している傾向が見られた．また日中では瀬戸内海から吹く2つの海風の冷却効果により気温分布が形成され，その恩恵を受けにくい内陸や地形の入り組んだ箇所で高温化しやすい．一方で夜間は山の斜面からの夜間冷気流が発生し，その冷却効果により気温が低くなると考えられる地点が見られた．

In recent years, urban warming has occurred, which has a serious negative impact on people's lives, especially in the summer. In addition, it expected that increase of elderly people with depopulation will forms vulnerable society to the urban warming in the future. Therefore, it is necessary to reorganize the urban structure to cope with a population decline, and to consider how to reduce the increase of the risk of urban warming at the same time especially in regional cities.
In this paper, as a first step, we conducted an air temperature measurement survey in the entire Fukuyama City and extracted high and low air temperature areas based on the results of air temperature distribution maps and cluster analysis. As a result, high air temperature areas tend to locate around urban centers both day and night. During the daytime, the two sea breezes blowing from the Seto Inland Sea provide cooling effect, while inland and areas with complicated topography tends to be hotter because of less benefit from sea breeze. During the nighttime, there were some measurement points which the air temperature was lower due to the cooling effect of the nighttime cold airflow
from the mountain slope.