托福听力

🎧 听力原文

Listen to part of a lecture in an environmental science class. Professor: Today we're going to 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 heat from the sun more than natural landscapes like forests or water bodies. Additionally, waste heat from vehicles, air conditioners, and industrial processes adds to the effect. Interestingly, the temperature difference can be as much as 5 to 10 degrees Celsius on clear, calm nights. This extra heat has consequences. It increases energy consumption for cooling, raises air pollution levels, and can even affect human health, especially during heat waves. But there are solutions. One effective method is to increase the albedo, or reflectivity, of surfaces by painting roofs white or using reflective materials. Another is to plant more trees and create green roofs, which provide shade and cool the air through evapotranspiration. Some cities are also implementing cool pavements that reflect more sunlight. So, as you can see, urban planning plays a crucial role in mitigating this climate effect.