I see I have some folks interested, so lets keep this going. A commenter writes

To give Karl more data:


I.e. the defrosting of the permafrost areas is expected above 500 ppm. The permafrost layer alone contains methane equivalent to 400 ppm of atmospheric CO2.

That makes 500+400 = 900 ppm of CO2 equivalent. Should I continue the calculations with suspected deep sea methane deposits?

Karl, we are driving a muscle car at 7000 rpm and have no idea what the engine does at 10,000 or 15,000 rpm.

Your point of handling global warming via migration is akin to suggesting that those vibrations that can be felt at 7000 rpm should be solved by passengers shuffling away from the middle of the accelerating car …

My general crisis management strategy is to first consider the far outlier and then work back in.

So, yes lets at minimum assume the permafrost goes and we get 900 ppm. If deep sea methane is even a slight possibility, lets add that as well and outline the scenario.

My understanding is that PETM was equivalent to 1700 ppm.

So at least some baseline questions would be

  • In an extreme scenario can we get to or cross 1700 ppm equivalent?
  • If we reach 1700 ppm-e what is the maximum rate at which the earth could close in on equilibrium temperatures?
  • Will any quasi-reasonable amount of force make our Diff-EQ system overshoot or can we expect a 20C+ ceiling?

Crowd sourcing this will help because so much of the literature is focused on 2C+ or 4C+ max and we really want to talk about 20C+ scenarios.