Listen to part of a lecture in an environmental science class. Professor: Today we're talking about urban heat islands. Now, cities are often warmer than surrounding rural areas. This is due to several factors. First, buildings and roads made of concrete and asphalt absorb and retain heat during the day and release it slowly at night. Second, there's less vegetation, which means less shade and less cooling through evapotranspiration. Also, waste heat from vehicles and air conditioners adds to the effect. However, there are solutions. One is to increase green spaces, like parks and green roofs. Another is to use cool pavements that reflect more sunlight. But here's an interesting twist: a study in Phoenix found that while planting more trees can reduce temperatures, it also increases humidity, which may make it feel less comfortable. So, urban planners need to balance these effects carefully. The key is designing cities with both temperature and human comfort in mind.
❓ 题目 What is the main point the professor makes about solutions to urban heat islands?
A. A: They are easy to implement but have little effect.
B. B: They may have unintended consequences like increased humidity.
C. C: They are only effective in dry climates like Phoenix.
D. D: They focus primarily on reducing vehicle emissions.
✅ 正确答案
B: They may have unintended consequences like increased humidity.