TOEFL Listening

🎧 Listening Transcript

Listen to part of a lecture in an environmental science class. Professor: Today we're going to talk about urban heat islands. Now, cities are often warmer than the surrounding rural areas. This is because concrete and asphalt absorb and re-radiate heat more than natural surfaces like soil and vegetation. Also, buildings block wind and trap heat, and human activities generate additional heat. But there are ways to mitigate this effect. One approach is to increase green spaces, such as parks and green roofs. Plants provide shade and release moisture through evapotranspiration, which cools the air. Another method is to use reflective materials for roofs and pavements. These materials, often light-colored, reflect more sunlight rather than absorbing it. Some cities have even implemented 'cool pavement' programs, painting roads with a reflective coating. However, these solutions require careful planning and investment. For example, green roofs need structural support and maintenance. But the benefits are significant: lower energy consumption, improved air quality, and reduced heat-related health risks. So, while urban heat islands are a challenge, they are not insurmountable.