Listen to part of a lecture in an environmental science class.
Today we're going to talk about the urban heat island effect, a phenomenon where cities are significantly warmer than surrounding rural areas. This happens because materials like concrete and asphalt absorb and re-radiate heat more than natural surfaces such as soil and vegetation. Additionally, human activities, including transportation and industrial processes, generate waste heat. The difference in temperature can be as much as 10 degrees Fahrenheit on clear, calm nights. To mitigate this effect, many cities are implementing green infrastructure. For example, planting trees provides shade and cools the air through evapotranspiration. Cool roofs, which are painted white or reflective colors, can reduce heat absorption. Some cities also create green roofs, covering rooftops with vegetation, which not only insulate buildings but also absorb rainwater, reducing runoff. While these solutions are promising, they require substantial investment and maintenance. Nevertheless, as global temperatures rise, addressing urban heat islands becomes increasingly critical for public health and energy conservation.
❓ Pregunta According to the professor, what are two examples of green infrastructure mentioned to reduce the urban heat island effect?
A. Planting trees and using cool roofs
B. Building taller buildings and increasing public transport
C. Using more concrete and installing air conditioning
D. Creating parks and constructing underground parking
✅ Respuesta correcta
Planting trees and using cool roofs
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