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Methane gas is a form of greenhouse gas that is over 20 times more effective than carbon dioxide in trapping heat in the atmosphere. Methane gas can remain in the atmosphere for about 9 to 15 years. Methane is emitted from a number of natural and human-influenced sources.ethane gas is a form of greenhouse gas that is over 20 times more effective than carbon dioxide in trapping heat in the atmosphere. Methane gas can remain in the atmosphere for about 9 to 15 years. Methane is emitted from a number of natural and human-influenced sources.
Pure argon is the most popular shielding gas and is often used for both gas metal arc and gas tungsten arc welding of aluminum. Mixtures of argon and helium are probably the next common, and pure helium is generally only used for some specialized GTAW applications.