The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil and methane clathrates.

Natural gas is found in deep underground natural rock formations or associated with other hydrocarbon reservoirs in coal beds and as methane clathrates.

Methane can be found in hydrocarbon fields, alone, associated with oil, or in the form of methane clathrates.

Methane clathrates are also present in deep Antarctic ice cores, and record a history of atmospheric methane concentrations, dating to 800, 000 years ago.

The clathrates in these deep deposits are thought to have formed in situ from the microbially produced methane, as the δ < sup > 13 </ sup > C values of clathrate and surrounding dissolved methane are similar.

In some regions ( e. g., Gulf of Mexico ) methane in clathrates may be at least partially derived from thermal degradation of organic matter, dominantly in petroleum.

Climate scientists such as James E. Hansen hypothesize that methane clathrates in the permafrost regions will be released as a result of global warming, unleashing powerful feedback forces which may cause runaway climate change that cannot be controlled.

Since methane clathrates are stable at a higher temperature than liquefied natural gas ( LNG ) (− 20 vs − 162 ° C ), there is some interest in converting natural gas into clathrates rather than liquifying it when transporting it by seagoing vessels.

The dark material itself may have formed as a result of radiation processing of methane clathrates or radiation darkening of other organic compounds.

Large populations of animals can be supported by chemosynthetic secondary production at hydrothermal vents, methane clathrates, cold seeps, whale falls, and isolated cave water.

Under the correct conditions of pressure and temperature, biogenic methane can accumulate in massive deposits of methane clathrates, which account for a significant fraction of organic carbon in continental margin sediments and represent a key reservoir of a potent greenhouse gas.

* Clathrate gun hypothesis-the hypothesis that melting methane clathrates could trigger runaway or very severe global warming.

* In John Barnes ' science-fiction novel Mother of Storms, the destruction of Arctic sea bed clathrates and the subsequent release of trapped and methane is central to the plot development involving a vast supersonic hurricane.

These are usually interpreted as caused by abrupt releases of methane from clathrates ( frozen methane ices that accumulate at the bottom of the ocean ), though some scientists dispute that methane would be sufficient to cause the observed changes.

In 2004 the global inventory of ocean methane clathrates was estimated to occupy between one and five million cubic kilometres.

Liquid propellants generally have densities similar to water ( with the notable exceptions of liquid hydrogen and liquid methane ), and these types are able to use lightweight, low pressure tanks and typically run high-performance turbopumps to force the propellant into the combustion chamber.

Sewer gas typically has a rotten egg smell and can contain methane gas, which is explosive, or hydrogen sulfide gas, which is deadly.

The gases always include a carbon source, typically methane, and hydrogen with a typical ratio of 1: 99.

While coal mining typically releases explosive methane gas, the location of the mine was in an area of Pictou County that had an unusually high level of methane.

Coalbed methane wells often produce at lower gas rates than conventional reservoirs, typically peaking at near per day ( about 0. 100 m³ / s ), and can have large initial costs.

LNG typically contains more than 90 % methane.

In chemical ionization a reagent gas, typically methane or ammonia is introduced into the mass spectrometer.

Methylotrophic organisms are able to grow at the expense of one or more of the compounds typically used by methophiles, but cannot use methane.

Often, methane is the gas of next highest concentration, but typically remains at nontoxic levels, especially in properly vented systems.

An explanation for some of the disappearances has focused on the presence of large fields of methane hydrates ( a form of natural gas ) on the continental shelves.

It has been hypothesized that periodic methane eruptions ( sometimes called " mud volcanoes ") may produce regions of frothy water that are no longer capable of providing adequate buoyancy for ships.

This project has also been approved by the Executive Board of the United Nations Framework Convention on Climate Change ( UNFCCC ) for reduction of emission of methane gas into the climate and has been registered with a capacity of reducing 108, 686 metric tonnes CO2 equivalent per annum.

Release or burning of methane would of course at least partially offset the obtained sequestration result – except when the gas is allowed to escape into the atmosphere in significant quantities: methane has a higher global warming potential than CO < sub > 2 </ sub >.

* Natural gas ( methane ), used by many for home cooking on gas stoves, has a cyan colored flame when burned.

Thus methane has a potential of 25 over 100 years but 72 over 20 years ; conversely sulfur hexafluoride has a GWP of 22, 800 over 100 years but 16, 300 over 20 years ( IPCC TAR ).

Production of methane from Lake Kivu began in 1983, but to date has been used only by the Bralirwa Brewery.

It has been proposed that rise of free oxygen that occurred during the Great Oxygenation Event removed methane in the atmosphere through oxidation.

Unlike CO < sub > 2 </ sub >, methane has a well-defined lifetime in the atmosphere of about 12 years.

It has been proposed that this theory was suggested to him either by researches on ethylene ( olefiant gas ) and methane ( carburetted hydrogen ) or by analysis of nitrous oxide ( protoxide of azote ) and nitrogen dioxide ( deutoxide of azote ), both views resting on the authority of Thomas Thomson.

Triton has a tenuous nitrogen atmosphere, with trace amounts of carbon monoxide and small amounts of methane near the surface.

The chamber has a quadrupole and can be filled-up with reaction ( or collision ) gases ( ammonia, methane, oxygen or hydrogen ), with one gas type at a time or a mixture of two of them, which reacts with the introduced sample, eliminating some of the interference.

" Others argue instead that methane might have been the gas emitted from the chasm, or CO < sub > 2 </ sub > and H < sub > 2 </ sub > S, arguing that the chasm itself might have been a seismic ground rupture, although this idea has been challenged by scholars such as Joseph Fontenrose and Lisa Maurizio, who argue that the ancient sources uniformly represent the Pythia speaking intelligibly, and giving prophecies in her own voice.

Despite its short atmospheric half life of 7 years, methane has a global warming potential of 62 over 20 years and 21 over 100 years ( IPCC, 1996 ; Berner and Berner, 1996 ; vanLoon and Duffy, 2000 ).

The sudden release of large amounts of natural gas from methane clathrate deposits has been hypothesized as a cause of past and possibly future climate changes.

Recent research carried out in 2008 in the Siberian Arctic has shown millions of tonnes of methane being released with concentrations in some regions reaching up to 100 times above normal.

In experimental work at University of Alaska Fairbanks, a 1000-litre digested using psychotropics harvested from " mud from a frozen lake in Alaska " has produced 200 – 300 liters of methane per day, about 20 – 30 % of the output from dig esters in warmer climates.

Every permutation of fluorine, chlorine, and hydrogen based on methane and ethane has been examined and most have been commercialized.

At the same time, agriculture has been shown to produce significant effects on climate change, primarily through the production and release of greenhouse gases such as carbon dioxide, methane, and nitrous oxide, but also by altering the Earth's land cover, which can change its ability to absorb or reflect heat and light, thus contributing to radiative forcing.