Narrator: Listen to part of a lecture in an environmental science class. Professor: Today we're going to talk about a surprising factor in climate change: the role of forests as carbon sinks. You might think that planting more trees is always beneficial, and in many cases, it is. But recent research shows that in some regions, especially boreal forests in the far north, trees can actually contribute to warming. How? Well, dark evergreen trees absorb more sunlight than the bright snow-covered ground they replace, which increases heat absorption. Also, these forests release volatile organic compounds that can form aerosols, which may have a cooling effect, but the overall impact is complex. In contrast, tropical forests have a strong cooling effect due to high evaporation and cloud cover. So, when we design reforestation projects, we need to consider location and species carefully. A blanket policy of 'plant more trees' might not always help mitigate climate change as we expect.
❓ 题目 What is the main point the professor makes about forests and climate change?
A. All forests equally help cool the climate by absorbing carbon dioxide.
B. The climate impact of forests depends on their location and type.
C. Boreal forests are more effective at cooling than tropical forests.
D. Planting trees is always a reliable solution to global warming.
✅ 正确答案
The climate impact of forests depends on their location and type.