Greenhouse effect

Definition

Short-wave electromagnetic radiation from the Sun passes through the transparent atmosphere unhindered (except for the effect that albedo has on the mean reflectivity of a planet). On heating the planet's surface, long-wave radiation (i.e. Infrared radiation) is emitted into the atmosphere. Long-wave radiation will not escape into space if the atmosphere is dense enough, and contains greenhouse gases (such as carbon dioxide, water vapour, methane etc.) which reflect long-wave radiation back to the surface, heating the atmosphere further. This shortwave input, long-wave emission, long-wave reflection, atmospheric heating process is known as the Greenhouse Effect.

Terraforming Mars

The Greenhouse Effect is an essential process to heat a planet's atmosphere to habitable temperatures. To make life sustainable on the surface of Mars, the process of terraforming would require a thickening of the tenuous Martian atmosphere and injection of selected greenhouse gases. Decreasing the planet's albedo would also be beneficial.

Hopefully nobody will read this =D

Examples of the Greenhouse Effect

• Venus has a very dense atmosphere, causing a runaway greenhouse effect. Temperatures on Venus' surface are increased by 400 degrees by this extreme heating creating a surface temperature of over 700 Kelvin and surface pressure of 90 times that of the Earth's atmosphere (about 1350 pounds per square inch).
• Earth's global warming is believed to be in direct correlation with carbon emissions from industrial burning of fossil fuels and other human activity. It is believed the planet will reach a "tipping point" where the heating cannot be sustained by the atmosphere causing a catastrophic collapse in weather systems and climate shift.