About the Greenhouse Gases

Concentrations of Greenhouse Gases in the Atmosphere

Carbon dioxide: It is released into the atmosphere by the burning of solid waste, wood and wood products, and fossil fuels.

Nitrous oxide: Emissions occur during various agricultural and industrial processes, and when solid waste or fossil fuels are burned.

Methane: Is emitted when organic waste decomposes, whether it be in landfills or in connection with livestock farming. Methane emissions also occur during the production and transportation of fossil fuels.

Ozone: When gasoline and coal are burned, nitrogen oxide gases and volatile organic compounds are released into the air, and during warm, sunny days, they are going to combine with oxygen to form ozone. High concentrations or ozone are often formed during the heat of the afternoon, and are likely to dissipate later in the evening, as the air cools.

Water Vapour: It is the most important greenhouse gas, and accounts for about 60% of the greenhouse gases of the greenhouse effect. It participates in the additional absorption of heat in the atmosphere which is exclusively caused by humans.

Sources:
http://environment.about.com/od/faqglobalwarming/f/greengases.htm
http://www.espere.net/Unitedkingdom/water/uk_watervapour.html
Picture: http://minnesotansforglobalwarming.com/m4gw/2010/07/shouldnt-we-be-worried-about-global-cooling.html