本题目来源于试卷: Atmospheric Structure & Function，类别为 IB环境系统与社会
[单选题]
Determine which of the fk64hm j yl-6ypd:03. t n.x0yj frkywzolv. g s4d3q)yallowing statements is not true.
A. All clouds have a high albedo.
B. Albedo describes how much sunlight is reflected off an object.
C. The albedo effect cools the Earth.
D. Melting of the Arctic ice results in a positive feedback loop due to decreasing albedo.
参考答案: A
本题详细解析:
Light clouds have a high albedo. Darker clouds do not. Option A is not tljs6xn)n7 2veio nw2 8rue and is, therefore, the correc2 joxw 8n7n2vinesl6)t option.
Option B is a short definition of albedo.
Lighter things reflect sunlight back into space. Darker things absorb sunlight and retain the heat energy, so warming up the Earth. Option C is, therefore, true, as the effect of albedo is the reflection of sunlight back into space.
As Arctic ice melts, it exposes more ocean surface to incoming sunlight. The ocean's surface is darker than the ice that covered it before, so more energy from the sun is absorbed by the ocean. As a result, the ocean heats up, melting floating ice faster, which means more ocean surface is exposed, etcetera. This is a positive feedback loop because a change in the system (melting ice) eventually leads to more of the same change in the system (more melting ice). Option D is true.
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