Scientists in Brazil monitored methane emissions from cattle farms and rice paddies. Which statement correctly explains why methane is classified as a greenhouse gas?

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Question

Scientists in Brazil monitored methane emissions from cattle farms and rice paddies. Which statement correctly explains why methane is classified as a greenhouse gas?

Accepted Answer

Methane absorbs infrared radiation and re-emits it, warming the atmosphere — Award 1 mark for correct mechanism of greenhouse effect. A is incorrect — greenhouse gases absorb infrared, not reflect ultraviolet. C is incorrect — while methane can be oxidised, this does not explain its greenhouse effect. D is incorrect — methane does not deplete the ozone layer; this is caused by CFCs.

Answer

Methane reacts with oxygen to form carbon dioxide

Answer

Methane absorbs infrared radiation and re-emits it, warming the atmosphere

Answer

Methane reflects ultraviolet radiation back into space

Answer

Methane depletes the ozone layer allowing more heat to enter

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