Today in our environmental science lecture, we'll discuss urban heat islands. Cities tend to be warmer than surrounding rural areas due to concrete and asphalt absorbing sunlight. One surprising factor is that green roofs, which are covered with plants, can reduce rooftop temperatures by up to 30 degrees Celsius. However, their overall effect on city-wide cooling is limited because they cover only a small fraction of building surfaces. Another method, using reflective paints on roofs, has been shown to lower energy consumption for cooling by 10 to 15 percent. While both approaches are beneficial, reflective paints are more cost-effective for large-scale application.
❓ ¿Qué dice el conferenciante sobre los techos verdes?
A. Son más efectivos que las pinturas reflectantes para reducir las temperaturas urbanas.
B. Pueden reducir significativamente las temperaturas en los techos, pero tienen un impacto limitado a nivel de toda la ciudad.
C. Son el método más rentable para edificios grandes.
D. Reducen el consumo de energía entre un 10 y un 15 por ciento.
✅ 正确答案
They can significantly lower rooftop temperatures but have limited city-wide impact.