Listen to part of a lecture in an environmental science class.
Today we're going to talk about urban heat islands, which are areas in cities that are significantly warmer than surrounding rural areas. This happens because buildings, roads, and other infrastructure absorb and re-emit heat from the sun more than natural landscapes do. For example, asphalt and concrete have low albedo, meaning they reflect less sunlight and absorb more heat. Also, cities have fewer trees and green spaces, which normally provide shade and cool the air through evapotranspiration. The heat island effect can raise city temperatures by several degrees, especially at night. This leads to increased energy consumption for air conditioning, higher air pollution levels, and even heat-related health issues. To combat this, some cities are adopting green roofs, planting trees along streets, and using lighter-colored materials for pavements. These measures can help reduce the temperature difference and make cities more livable.
❓ Question According to the lecture, what is one primary cause of the urban heat island effect?
A. Increased use of air conditioning in cities
B. Low albedo of building materials like asphalt
C. Lack of wind due to tall buildings
D. Excessive heat generated by factories
✅ Correct Answer
Low albedo of building materials like 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
