Аудирование TOEFL

🎧 Транскрипт аудио

Today we're going to discuss the concept of 'urban heat islands' and how they affect local climates. Urban areas, with their dense concentration of buildings, roads, and other infrastructure, tend to absorb and re-emit more heat than natural landscapes. This is primarily because materials like concrete and asphalt have high thermal mass and low albedo, meaning they absorb more sunlight and release it slowly. Additionally, the lack of vegetation reduces shade and evapotranspiration, which would otherwise cool the air. As a result, cities can be several degrees warmer than surrounding rural areas, a phenomenon known as the urban heat island effect. This effect is not uniform; it varies with time of day, season, and local weather conditions. For instance, the effect is typically strongest at night when buildings slowly release the heat they absorbed during the day. Now, what can be done to mitigate this? One effective strategy is increasing green spaces, such as parks and green roofs, which provide shade and promote cooling through evapotranspiration. Another approach is using reflective materials for pavements and rooftops to reduce heat absorption. These measures not only lower temperatures but also reduce energy consumption for air conditioning, thus benefiting both the environment and public health.