Question

Methane is a green house gas because

• A. It absorbs longer wavelengths of the electromagnetic spectrum while transmitting shorter wavelengths
• B. It absorbs shorter wavelengths of the electromagnetic spectrum while transmitting longer wavelengths
• C. It absorbs all wavelengths of the electromagnetic spectrum
• D. It transmits all wavelengths of the electromagnetic spectrum

Answer 1

The correct option is A It absorbs longer wavelengths of the electromagnetic spectrum while transmitting shorter wavelengths

Methane allows sunlight (shortwave radiation) to pass through the atmosphere freely, where it is then partially absorbed by the surface of the Earth. But some of this energy bounces back out towards space as heat. Of the heat emitted back to space, some is intercepted and absorbed by methane in the atmosphere. This molecular structure allows it to absorb some of the escaping heat and then re-emit it towards the Earth which increases global temperatures.