雅思听力

🎧 Listening Transcript

Today in our environmental science lecture, we'll discuss urban heat islands. These occur when cities are significantly warmer than surrounding rural areas. One major cause is the replacement of natural surfaces with asphalt and concrete, which absorb and retain heat. Another factor is the lack of vegetation, as trees provide shade and release moisture through transpiration. Interestingly, studies show that the temperature difference can be as high as 10 degrees Celsius on clear, calm nights. To mitigate this effect, cities are implementing green roofs and increasing tree canopy. However, these solutions require substantial investment and long-term planning. Now, let's examine a case study from Melbourne, where they've seen a 4-degree reduction in peak summer temperatures after planting over 70,000 trees.