Good morning, everyone. Today we're going to look at how urban trees affect city temperatures. A recent study in Melbourne compared two streets: one with a dense canopy of mature elms, and another with only young, sparse plantings. Over a summer week, the shaded street had an average surface temperature that was 4.2 degrees Celsius lower than the exposed street. Interestingly, the air temperature difference was smaller, only about 1.1 degrees, because wind mixed the air. However, the researchers noted that the cooling effect increased significantly when tree canopies covered more than 30% of the street area. They also found that the type of tree mattered less than the overall leaf density.
❓ ¿Cuál fue el hallazgo principal respecto a la diferencia entre las dos calles?
A. A. La temperatura del aire era mucho más baja en la calle sombreada.
B. B. La diferencia de temperatura superficial fue mayor que la diferencia de temperatura del aire.
C. C. El tipo de árbol fue el factor más importante para la refrigeración.
D. D. El efecto de enfriamiento fue insignificante cuando la cobertura del dosel era inferior al 30%.
✅ 正确答案
B. The surface temperature difference was greater than the air temperature difference.