TOEFL Listening

🎧 Listening Transcript

Listen to part of a lecture in an environmental science class. The professor is discussing the concept of urban heat islands. Professor: Urban areas tend to be warmer than surrounding rural areas, a phenomenon known as the urban heat island effect. This happens because buildings, roads, and other infrastructure absorb and re-emit the sun's heat more than natural landscapes do. For example, dark rooftops and asphalt parking lots can reach temperatures significantly higher than nearby vegetated areas. Additionally, human activities, such as driving cars and running air conditioners, generate waste heat. The lack of vegetation also reduces shade and evapotranspiration, which normally cools the air. To mitigate this effect, many cities are implementing strategies like installing green roofs, planting more trees, and using reflective materials on pavements. These measures can lower surface temperatures and improve energy efficiency. However, the effectiveness varies depending on local climate and city design. So while there is no single solution, a combination of approaches often yields the best results.