Infrared
3 marks · NormalExplain why infrared radiation from the Sun is able to warm the Earth's surface, even though the Earth's atmosphere is mostly transparent to visible light.
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Must show: Infrared passes through atmosphere, Reaches and heats Earth's surface, Some is absorbed and some is reflected
Common mistakes: Confusing energy types
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Marking points
B1 · 1 mark · States that infrared can pass through the atmosphere.
B2 · 1 mark · Explains that infrared reaches the surface and is absorbed.
B3 · 1 mark · Mentions that absorption causes warming of the surface.
Worked solution
Infrared radiation from the Sun passes through the Earth's atmosphere and is absorbed by surfaces like land and water. This absorption increases their temperature. Since the atmosphere lets most infrared pass, the Earth's surface is warmed by this energy.