Today in our environmental science lecture, we'll discuss urban heat islands. As cities grow, concrete and asphalt absorb sunlight and re-radiate heat, making urban areas warmer than surrounding rural regions. This effect is intensified by tall buildings that block wind and reduce cooling. A key solution is increasing green spaces, like parks and green roofs, which provide shade and release moisture. However, planting trees alone isn't enough; we must also consider building materials with higher reflectivity. For instance, using white or light-colored roofs can significantly lower surface temperatures. In our case study of Melbourne, researchers found that combining green roofs and reflective pavements reduced peak summer temperatures by up to 4 degrees Celsius. So, the most effective approach involves multiple strategies working together.