Narrator: 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 materials like concrete and asphalt absorb and retain heat from the sun during the day, and then release it slowly at night. In contrast, rural areas with vegetation and soil tend to cool down faster. One major factor is the lack of trees and green spaces in cities, which reduces shade and evapotranspiration—the process by which plants release water vapor, cooling the air. Another factor is waste heat from buildings, vehicles, and air conditioning systems. To mitigate this effect, some cities are implementing green roofs, which are covered with vegetation, and cool pavements that reflect more sunlight. These strategies not only lower temperatures but also reduce energy consumption for cooling. However, the effectiveness of these measures depends on the local climate and the scale of implementation. So, while green roofs are promising, they are not a one-size-fits-all solution.
❓ 質問 According to the professor, what is one reason why urban areas are warmer than rural areas?
A. A. Rural areas have more waste heat from vehicles.
B. B. Urban materials like concrete absorb and retain heat.
C. C. Cities are located in warmer climates.
D. D. Vegetation in cities increases humidity.
✅ 正解
B. Urban materials like concrete absorb and retain heat.
TOEFL Listening Tips
Skim the questions first to predict the content
Watch for signal words in lectures and conversations (however, actually, in fact)
For main idea questions, focus on the beginning; for detail questions, focus on examples and data
For attitude questions, pay attention to the speaker's tone and word choice
Take notes on keywords; don't try to write down every word