How will the release of Siberian methane affect global warming? Can climate models predict its signature?

Because it’s a complicated process, and we can’t predict how much of the released gas may be re-absorbed by plants and the oceans, how quickly it will be released, or whether the sudden increase in methane will trigger an, as yet, un-predicted event. It is estimated that a Siberian thaw could push 500 billion tonnes of carbon dioxide gas into the atmosphere. The U.N.-sponsored Panel on Climate Change has published its estimate for global warming over the next one hundred years, producing a rise of between 3 and 11 degrees F. The addition of Siberian gas releases could change these predictions to 5 to 15 degrees F.