The heat island effect (HIE) is a regional climate anomaly, occurring in most big cities around the world. Basically, it means that at any particular time, a metropolitan environment will be significantly warmer than its rural surroundings. There are a number of factors contributing to HIE.
熱島效應是世界各大城市共通的區域性氣候異常現象，簡單來說便是，無論何時，都市溫度都比周邊地區異常的高（舉例而言，台北市夏日正午的溫度就比鄰近地區足足高出 4.5℃）。