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We can see that there are large buildups of methane clathrates in permafrost regions.

Climate scientist James Hansen has predicted that the release of the permafrost methane clathrates could cause runaway climate change.

We know that some have related the Triassic Extinction event to the release of Permafrost Clathrates.

Do we know how much methane is stored in the permafrost? Do we know at what temperature it will be released? Can we model the release of methane into the atmosphere in the same way we can model the release of carbon dioxide?

My question is: Is there evidence to suggest that the release of methane clathrates in permafrost regions will impact climate change?

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Your first two links don't seem to mention clathrates.

Much ado about methane says:

What methane are we talking about?
The largest methane pools that people are talking about are in sediments of the ocean, frozen into hydrate or clathrate deposits (Archer, 2007). The total amount of methane as ocean hydrates is poorly constrained but could rival the rest of the fossil fuels combined. Most of this is unattractive to extract for fuel, and mostly so deep in the sediment column that it would take thousands of years for anthropogenic warming to reach them. The Arctic is special in that the water column is colder than the global average, and so hydrate can be found as shallow as 200 meters water depth.
On land, there is lots of methane in the thawing Arctic, exploding lakes and what not. This methane is probably produced by decomposition of thawing organic matter. Methane could only freeze into hydrate at depths below a few hundred meters in the soil, and then only at “lithostatic pressure” rather than “hydrostatic”, meaning that the hydrate would have to be sealed from the atmosphere by some impermeable layer.
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The possibility of a catastrophic release is of course what gives methane its power over the imagination (of journalists in particular it seems). A submarine landslide might release a Gigaton of carbon as methane (Archer, 2007), but the radiative effect of that would be small, about equal in magnitude (but opposite in sign) to the radiative forcing from a volcanic eruption. Detectable perhaps but probably not the end of humankind as a species.

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It is very unlikely to happen, but yes, there is evidence that release of methane from permafrost deposits would accelerate climate change. There are also massive deposits of clathrates on the ocean bed. They are mostly in deep ocean where they are kept in cold storage at a permanent 4 C - 5C which never changes, even in the tropics, but some is in shallow temperate seas like the Baltic, where in extreme circumstances melting is not out of the question.

As you say, it is suspected that the Permo-Triassic extinction event of 250 million years ago was initiated by super-volcano eruptions in the Siberian Traps which caused the melting of large amounts of clathrates, raising average temperatures by about 10 C. It isn't possible to put an exact figure on the amount of clathrates in the arctic, but the amounts are substantial and enough to accelerate climate warming if they were released in a short span of time, centuries rather than millennia. Oceanic clathrates are far more substantial, and would be worth mining commercially if there was some easy way of getting at them. Articles fight shy of naming a specific melting point for methane ice, perhaps because the structure and therefore the melting point varies with different types,but it is comfortably above the melting point of water ice..

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  • $\begingroup$ "which never changes" [citation needed] $\endgroup$ – Semidiurnal Simon Aug 12 at 20:34

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