Good morning, everyone. Today we'll continue our discussion on environmental science, focusing on urban heat islands. As we know, cities tend to be warmer than surrounding rural areas due to concrete and asphalt absorbing heat. However, a recent study in Melbourne found that increasing tree canopy by just 20% could reduce surface temperatures by up to 4 degrees Celsius. Interestingly, the study also noted that green roofs, while beneficial, had a smaller effect than street trees, because trees provide shade and evaporative cooling. The researchers emphasized that planting trees along streets, especially in residential areas, is the most cost-effective strategy.
❓ According to the lecture, what did the study in Melbourne find about reducing urban heat?
A. A. Green roofs are more effective than street trees.
B. B. Increasing tree canopy by 20% could lower temperatures by about 4 degrees.
C. C. Concrete and asphalt help reduce heat absorption.
D. D. Residential areas have no impact on urban heat islands.
✅ 正确答案
B. Increasing tree canopy by 20% could lower temperatures by about 4 degrees.