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 re-emit heat from the sun more than natural landscapes do. Additionally, waste heat from vehicles, air conditioners, and industrial processes adds to the effect. Vegetation, which provides shade and releases moisture through transpiration, is often scarce in dense urban areas, further reducing cooling. One surprising consequence is that urban heat islands can increase energy demand for cooling, which ironically leads to more greenhouse gas emissions. Some cities are implementing solutions like green roofs, which are covered with plants, and cool pavements that reflect more sunlight. These strategies not only lower temperatures but also improve air quality and reduce stormwater runoff. However, their effectiveness varies based on local climate and city design. Now, what might be a key takeaway from this?
❓ Вопрос According to the professor, what is one factor that contributes to the urban heat island effect?
A. The presence of large bodies of water near cities
B. The use of materials like concrete and asphalt
C. The high altitude of urban areas
D. The lack of wind in city centers
✅ Правильный ответ
The use of materials like concrete and asphalt
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
