การฟัง TOEFL

🎧 บทถอดเสียง

Narrator: Listen to part of a lecture in an environmental science class. Professor: Today, let's talk about urban heat islands, a phenomenon where cities are significantly warmer than surrounding rural areas. This happens because concrete and asphalt absorb and re-radiate heat, and there's less vegetation to provide shade and cooling through evapotranspiration. One major consequence is increased energy consumption for air conditioning, which in turn leads to higher greenhouse gas emissions. However, there are practical solutions. For instance, green roofs—covered with plants—can reduce rooftop temperatures by up to 40 degrees Celsius. Another approach is increasing albedo, or reflectivity, by painting roofs and pavements white or using reflective materials. These strategies not only lower city temperatures but also improve air quality and reduce stormwater runoff. Interestingly, studies show that even small-scale changes, like planting street trees, can have a measurable impact on local cooling. So, while the problem is complex, targeted interventions can make a meaningful difference.