Comprensión auditiva TOEFL

🎧 Transcripción de audio

Listen to part of a lecture in an environmental science class. The professor is discussing the concept of urban heat islands. "Now, urban areas tend to be warmer than the surrounding rural areas. This phenomenon is known as the urban heat island effect. There are several reasons for this. Buildings and roads absorb and re-radiate solar energy more effectively than natural landscapes, and they also block wind, reducing cooling. Additionally, heat generated from human activities—like cars, air conditioners, and industrial processes—adds to the warmth. The lack of vegetation and water bodies in cities means less evaporative cooling. Interestingly, the intensity of the heat island effect varies. It is usually strongest at night and during calm, clear weather, when rural areas cool off quickly but urban materials slowly release stored heat. This can lead to significant temperature differences, sometimes over five degrees Celsius. To mitigate this, cities are adopting strategies like planting trees, creating green roofs, and using reflective materials for pavements and buildings. These measures not only reduce temperatures but also lower energy consumption for cooling, which further cuts down on greenhouse gas emissions." Now the professor will ask a question.