TOEFL Listening

🎧 Listening Transcript

Narrator: 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, sometimes by as much as 5 to 10 degrees Fahrenheit. Why is that? Well, one major factor is the materials we use to build our cities. Asphalt and concrete absorb heat during the day and release it slowly at night. That's why cities stay warmer even after the sun goes down. Another factor is the lack of vegetation. Trees and plants provide shade and also cool the air through a process called evapotranspiration—water evaporates from leaves, which takes heat from the air. So when we remove trees and replace them with buildings and roads, we lose that cooling effect. But there are solutions. For example, some cities are painting rooftops white or installing green roofs—roofs covered with plants. These measures can significantly reduce surface temperatures. Also, planting more trees along streets can help. So, the key is to rethink how we design urban spaces to make them more sustainable. Now, any questions?