Today, in our environmental science lecture, we're discussing urban heat islands. You might think that planting more trees is the best solution, but recent studies show that reflective surfaces, like white roofs, can be more effective in reducing city temperatures. For example, in Los Angeles, a project to paint roofs white lowered local temperatures by up to 3 degrees Celsius. However, trees provide additional benefits such as improving air quality and supporting biodiversity. So, while white roofs offer immediate cooling, trees are a long-term investment. The key is to combine both strategies depending on the city's climate and infrastructure.