What Is the Urban Heat Island Effect—and Why Is It Now a Boardroom Issue? Step into any major city during peak summer and you can feel it immediately—the air feels heavier, hotter, almost trapped. This is the urban heat island (UHI) effect in action, where cities register temperatures several degrees higher than surrounding rural areas. According to recent climate assessments, urban zones can be up to 7°C warmer, driven by dense infrastructure, dark surfaces, and limited gree