雅思听力

🎧 Listening Transcript

Today in our environmental science lecture, we'll discuss urban heat islands. Cities tend to be warmer than surrounding rural areas because concrete and asphalt absorb and re-radiate heat. One effective mitigation strategy is increasing green spaces, such as parks and green roofs. However, a recent study found that the cooling effect of parks depends significantly on their size and the density of trees. Small parks with scattered trees provide limited relief, while large, densely wooded parks can lower local temperatures by up to 5 degrees Celsius. Additionally, reflective materials on buildings and pavements can reduce heat absorption, but they are less effective than vegetation in promoting evaporation.