Greenhouse effect

Environmental policy - atmosphere - greenhouse gases.

The greenhouse effect contributes to global warming.

It is caused by gases in the upper atmosphere which both:

• Allow longer-wavelength warming radiation from the sun to pass down through to the lower atmosphere and the earth's surface; and simultaneously

• Reflect back down to the lower atmosphere and the earth's surface (shorter-wavelength) infra-red radiation emitted by the earth.

This happens because the greenhouse gases are relatively permeable by longer-wavelength radiation, allowing it to pass through and down to the earth, but relatively impermeable to shorter-wavelength radiation, reflecting it back down to the earth.

Venus is another planet which experiences a strong greenhouse effect.

See also

• Carbon credits
• Carbon dioxide equivalent
• Carbon footprint
• Carbon-neutral
• Carbon tax
• Corporate social responsibility
• Decarbonise
• Emissions
• Footprint
• Greenhouse gas
• Greenhouse Gas Protocol
• Kyoto Protocol
• Methane
• Montreal Pledge
• Renewables
• Streamlined Energy and Carbon Reporting