Urban heat islands are a big problem in cities due to rapid urbanization. A study used satellite images to look at how urban expansion and green spaces affect heat islands in Hangzhou city. They found that as the city grew, the hottest areas moved from north to south. The city center had less green space, making it even hotter. Different time periods showed different relationships between urban growth, green spaces, and heat islands. This information can help city planners and designers make cities cooler and more livable.