托福听力

🎧 听力原文

Listen to part of a lecture in an environmental science class. The professor is discussing the concept of urban heat islands. Professor: Today, let's talk about urban heat islands, a phenomenon where cities are significantly warmer than surrounding rural areas. This happens because concrete, asphalt, and buildings absorb and re-emit the sun's heat more than natural landscapes like forests or fields. Additionally, waste heat from vehicles and air conditioners adds to the effect. One major consequence is increased energy demand for cooling, which can lead to higher greenhouse gas emissions. But there are mitigation strategies. For example, planting more trees and creating green roofs can provide shade and evapotranspiration, which cools the air. Also, using reflective materials on rooftops and pavements, often called cool roofs and cool pavements, can reduce heat absorption. However, these solutions require careful planning and investment. Interestingly, studies show that even small parks can lower temperatures in their immediate vicinity by several degrees. So, urban design choices can significantly impact local climate.