I think that the estimate of the effects of the Arctic release are too high, but, given what we have already seen from the clathrates, something to consider.
So...this firestorm? If you think the fuel for your firestorm will be methane..you are in error. Methane is lighter than air. It just rises up and cannot ever get dense enough to be flammable. Now natural gas..which was the culprip in the BP explosion in the gulf IS heavier than air and once released in a closed environment is very dangerous. If say huge amounts of natural gas erupted from the ground it would form pools of highly explosive fuel at low points in our geography. Thing is though it would burn off quickly and only do the same kinda damage as a forest fire. No way it could cause a world wide firestorm. There just isn't enough of it.
Let me 'splain sumpn' to you, Lucy:
CH4 is out-gassing, from warming tundras and bodies of water, including from the bottom, of the Arctic Ocean, from melting glaciers, from Siberia, from Canada, from Alaska, from anywhere, but a lot comes from warming Arctic areas.
CH4 is 24 times as potent a greenhouse gas, as CO2, IF CH4 breaks down, to CO2 and H2O, on its normal timeline, which you can look up. But some studies indicate CH4 will be impaired, at breaking down, maybe by more H2O in the atmosphere, I forget, but I'll look it back up, and you can look it up, NOW.
The point is, CH4 will radically increase heat retention, in the atmosphere, greatly increasing likelihood, of wildfires, even if one of those mile-wide bubbles, from the bottom of the Arctic Ocean doesn't go BOOOOOOM, which one might do, someday.
If the exchange to CO2 and H2O is impaired, CH4 has a GWP (global warming potential) of 72 or even more. CO2 has a GWP of 1, but it is more common, in the air.
And natural gas is mostly CH4, but also:
Typical Composition of Natural Gas
Methane CH4 70-90%
Ethane C2H 60-20%
Propane C3H8
Butane C4H10
Carbon Dioxide CO2 0-8%
Oxygen O2 0-0.2%
Nitrogen N2 0-5%
Hydrogen sulphide H2S 0-5%
Rare gases A, He, Ne, Xe trace
Actually, the effects of CH4 outgassing is much worse than the figure of 24 times as effective as CO2 indictates. For that is the figure for the effect spread over a century. In the first decade, before much of it has oxidized into CO2 and H20, the figure is 60 to 100 times as effective of a GHG as CO2. As the amount of CH4 increases, the rate of reduction decreases because of the lowering of the amount of hydroxyl in the atmosphere. So the worse it get, the worser it gets LOL
Atmospheric methane - Wikipedia, the free encyclopedia
[edit] Removal processes
Any process that consumes methane from the atmosphere can be considered a "sink" of atmospheric methane. The most prominent of these processes occur as a result of methane either being destroyed in the atmosphere or broken down in soil.
A pie chart demonstrating the relative effects of various sinks of atmopsheric methane.
Reaction with the hydroxyl radical- The major removal mechanism of methane from the atmosphere involves radical chemistry; it reacts with the hydroxyl radical (·OH) in the troposphere or stratosphere to create the CH·3 radical and water vapor. In addition to being the largest known sink for atmospheric methane, this reaction is one of the most important sources of water vapor in the upper atmosphere.
CH4 + ·OH → ·CH3 + H2O
This reaction in the troposphere gives a methane lifetime of 9.6 years. Two more minor sinks are soil sinks (160 year lifetime) and stratospheric loss by reaction with ·OH, ·Cl and ·O1D in the stratosphere (120 year lifetime), giving a net lifetime of 8.4 years.[1] Oxidation of methane is the main source of water vapor in the upper stratosphere (beginning at pressure levels around 10 kPa).
The methyl radical formed in the above reaction will, during normal daytime conditions in the troposphere, usually react with another hydroxyl radical to form formaldehyde. Note that this is not strictly oxidative pyrolysis as described previously. Formaldehyde can react again with a hydroxyl radical to form carbon dioxide and more water vapor. Note that sidechains in these reactions may interact with nitrogen compounds that will likely produce ozone, thus supplanting radicals required in the initial reaction.[24]
Methanotrophic bacteria in soils- Methanotrophic bacteria that reside within soil use methane as a source of carbon in methane oxidation.[25] Methane oxidation allows methanotrophic bacteria to use methane as a source of energy, reacting methane with oxygen and as a result producing carbon dioxide and water.
CH4 + 2O2→ CO2 + 2H2O