托福听力

🎧 听力原文

Narrator: Listen to part of a lecture in an environmental science class. Professor: Today we're discussing the concept of 'urban heat islands.' As cities grow, they replace natural landscapes with concrete, asphalt, and buildings. These materials absorb and retain heat from the sun much more than vegetation does. As a result, urban areas can be significantly warmer than surrounding rural areas, sometimes by as much as five to ten degrees Fahrenheit. This phenomenon has several consequences. For one, it increases energy consumption because people use more air conditioning during hot summer months. It also raises the risk of heat-related illnesses, especially for vulnerable populations like the elderly. Interestingly, the heat island effect is not uniform across a city. Parks and green spaces can create cooler pockets, while dense downtown districts often experience the highest temperatures. To mitigate this, some cities are implementing green roofs, planting more trees, and using reflective materials on roads and buildings. These strategies not only cool the city but also reduce stormwater runoff and improve air quality. However, implementing them requires careful planning and investment. So, while the problem is serious, there are practical solutions being tested worldwide.