Greenhouse Gas Emissions

There are some gases such as carbone dioxide occur naturaly and are emitted to atmosphere through natural proceses and human activities, but some other gases are created and emitted only through human activities.
The most dangerous of them are:

Carbon Dioxide(CO2): Carbon dioxide enters the atmosphere through the burning of fossil fuels (oil, natural gas, and coal), solid waste, trees and wood products, and also as a result of other chemical reactions. Carbon dioxide is also removed from the atmosphere when it is absorbed by plants as part of the biological carbon cycle.

Methane(CH4): Methane is emitted during the production and transport of coal, natural gas, and oil. Methane emissions also result from agricultural practices and by the decay of organic waste in solid waste landfills.

Nitrous Oxide(N2O): Nitrous oxide is emitted during agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste.

Fluorinated Gases: Hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride are synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes. Fluorinated gases are sometimes used as substitutes for ozone-depleting substances (CFCs, HCFCs, and halons). These gases are typically emitted in smaller quantities, but because they are potent greenhouse gases, they are sometimes referred to as High Global Warming Potential gases.


During the next centurys the Greenhouse gas concentration in the atmosphere will increase unless humans stop the greenhouse gas emissions.The increasing of gas concentration on the atmosphere are very likely to increase Earth's average temperature,influence precipitation and the raise of the sea levels.The magnitude of these changes, however, is uncertain.










Sources: http://www.epa.gov/climatechange/index.html
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