การฟัง TOEFL

🎧 บทถอดเสียง

Listen to part of a lecture in an environmental science class. The professor is discussing the concept of urban heat islands. Professor: Urban areas tend to be warmer than surrounding rural areas, a phenomenon known as the urban heat island effect. This happens because concrete, asphalt, and buildings absorb and re-radiate solar heat more than natural landscapes like vegetation and soil. During the day, these materials store heat, and at night they release it slowly, preventing cities from cooling down as quickly as rural areas do. Additionally, human activities such as driving cars, running air conditioners, and industrial processes generate waste heat. The temperature difference can be especially noticeable on clear, calm nights, sometimes reaching several degrees Celsius. To mitigate this effect, cities have adopted strategies like planting trees, creating green roofs, and using reflective materials on pavements and buildings. These measures not only lower surface temperatures but also reduce energy consumption for cooling, improving comfort and air quality. However, implementing them requires careful planning and investment, and the benefits are most significant when applied on a city-wide scale.