Nope. Even today there are massive methane releases in tundra areas - and people don't "have to leave."
Is there any hope of you ever paying attention in good faith?
They will have to leave when and if it burns. It will burn when and if it dries out (much of it is extremely flammable, even after the methane has outgassed). It will dry out when and if it heats up (not much rain or snow up there). It will heat up when and if the methane release sufficiently overpowers the degradation capabilities that have been partially damping its effects so far (any time now).
As specifically and explicitly noted, above, for the reading pleasure of anyone actually curious or interested.
I have not dismissed anything. I am using the absolute upper limit of IPCC projections.
You are not using the absolute upper limits of the ranges of possibilities visible in the IPCC's graphs, the major research reports and scientific literature, etc.
There aren't any, for starters - there are just decreasing probabilities in the tails of the distributions. Meanwhile, the IPCC is well known to have been "conservative" in its reports - consistently downplaying and underestimating the rate and size of the CO2 boost's effects, especially in the high latitudes. (The permafrost melting, the Greenland and Antarctic melts, and the high latitude temperature spikes, have all been multiples - not just greater, but two and three times greater - than the IPCC projections, for example). You omitted all of those considerations - you say the omission was unintentional, not dismissal but ignorance? Ok. Consider yourself informed, in the future, and no more bs.
That is correct. It can also lead to dramatic cooling if the additional heat causes primarily day-side clouds. That's why it is one of the most uncertain feedbacks in the IPCC's predictions.
It would most likely - by a huge margin - lead to smaller increases in the daytime highs, not "cooling". Cooling would require not only a specific regime of daytime cloud cover, but a clearing and reduction of heat trapping at night somehow - a vanishingly improbable combination, much less likely than a partial slowing of an otherwise dramatic temperature boost. But that is not the main issue -
the main issue is that there is no safety in uncertainty, and deriving reassurance from a mere possibility that things might not turn out as bad as the data and theory indicates they well might is bizarrely naive. Pollyanna.
That is, your claim of pessimism is ill supported. Ignoring bad possibilities because they are not certain is optimism, not pessimism, and more than a little ditzy - prudence would pay attention to the actual odds, and assess risk accordingly.
Nope. Again, even today, in areas where there are massive wildfires, we are seeing tens to hundreds of dead. Not millions.
So?
What do you mean, "nope"? Why are you reposting matters of agreement and common observation?
You claimed if they got a thousand times worse, they would kill only a thousand times more people. You were using that inexplicably mistaken linearity to downplay the significance of the risks being run by boosting CO2 as we are.
That was, at best, a moment of odd carelessness on your part - you weren't thinking, despite being confronted. Surely you are not going to double down on such an assertion and such an approach to risk assessment?
If they were a thousand times worse in Australia, for example, they would kill almost everyone who failed to escape their region of the continent on maybe twelve hours notice. Major rivers and lakes would dry. The electrical system - including the phones, etc - would be wrecked. Major airports and roads would be shut down with little warning. The landscape currently most densely populated would be largely uninhabitable for the indefinite future - lacking food, water, fuel, and shelter. And most of the possible refuges within range, in continent or overseas, would be getting hammered as well.
Hell, that would happen if they were only four or five times worse. And we haven't begun to consider the heat waves, rainfall pattern changes, storm energy alterations, crop failures, ecological disasters, or economic dislocation effects. Nor have we factored in the probably simultaneous onset in Indonesia, China, India, Pakistan, and the Persian Gulf region - all of which would cripple Australia's ability to cope. 
