Other Greenhouse Gases

While some greenhouse gases (GHGs) are emitted into the atmosphere through natural processes, other GHGs are created and emitted through human activities. These include:

• Carbon dioxide (CO₂). Carbon dioxide enters the atmosphere through the burning of fossil fuels (e.g., oil, natural gas, and coal), trees and wood products, and solid waste; it is also released as a result of other chemical reactions (e.g., manufacturing of cement). Carbon dioxide is removed from the atmosphere (or sequestered) 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 livestock and other agricultural practices and by the decay of organic waste in municipal 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 (i.e., CFCs, HCFCs, and halons). These gases are typically emitted in smaller quantities; however, because they are potent greenhouse gases, they are sometimes referred to as high-global-warming-potential gases.

Southern Research provides independent evaluation of GHG emission sources and new technologies that reduce the emission of GHGs. While we have focused primarily on CO₂ and methane, Southern Research is also interested in the evaluation of emissions sources and reduction solution technologies for other primary GHGs, including N₂O, HFCs, and SF₆ as well as other potential emissions impacting climate change, such as black carbon.