Well, if the outcome is loss of our habitat then the eventual cost is the sum of the world's economy times however many years it would likely have gone on without the abuse of fossile fuels. And we don't have to compare to muscle power since there are existing methods (since at least the advent of nuclear power) on how to run a CO2 neutral economy with only a moderate immediate loss compared to what we're doing.
I'm afraid it's probably more necessary then, because you need sound justification for any action to be taken. I have to admit - I use models in my day job, and I'm nervous about binding law and treaties based on them.
And I don't see any projections where total loss of habitat is on the table. It'll be more like Mesa Verde, where pre-Industrial warming presumably rendered the home of the Anasazi uninhabitable. Even them that's 100 years out.
> And I don't see any projections where total loss of habitat is on the table.
The more I read about it, the more it seems to me that valuable information continues to be poisoned, clouding our judgement.
See for example the following extracts from wikipedia [1]:
> "Research carried out in 2008 in the Siberian Arctic has shown millions of tons of methane being released, apparently through perforations in the seabed permafrost,[20] with concentrations in some regions reaching up to 100 times normal levels.[22][23] The excess methane has been detected in localized hotspots in the outfall of the Lena River and the border between the Laptev Sea and the East Siberian Sea. Some melting may be the result of geological heating, but more thawing is believed to be due to the greatly increased volumes of meltwater being discharged from the Siberian rivers flowing north.[24] Current methane release has previously been estimated at 0.5 Mt per year.[25] Shakhova et al. (2008) estimate that not less than 1,400 Gt of carbon is presently locked up as methane and methane hydrates under the Arctic submarine permafrost, and 5–10% of that area is subject to puncturing by open taliks. They conclude that "release of up to 50 Gt of predicted amount of hydrate storage [is] highly possible for abrupt release at any time". That would increase the methane content of the planet's atmosphere by a factor of twelve,[26][27] equivalent in greenhouse effect to a doubling in the current level of CO2."
Yet in the same section, you know what the introduction text reads currently?
> "Most deposits of methane clathrate are in sediments too deep to respond rapidly, and modelling by Archer (2007) suggests the methane forcing should remain a minor component of the overall greenhouse effect.[17] Clathrate deposits destabilize from the deepest part of their stability zone, which is typically hundreds of metres below the seabed. A sustained increase in sea temperature will warm its way through the sediment eventually, and cause the shallowest, most marginal clathrate to start to break down; but it will typically take on the order of a thousand years or more for the temperature signal to get through.[17]"
So let me get this straight: Because someone found a model from 2007 that makes things look mostly fine, we ignore empirical data from 2008 that shows that a Clathrate Gun of 50 Gt could go off at any time? Please someone tell me how I'm wrong just so I don't have to go crazy here.
So, you want precedent for a loss of habitat? How about [2]? Now look, I'm not saying that this is a certainty. But one has to assign a percentage of risk for this happening. I can't do it, I'm not enough of a modeller, but so far I haven't found any conclusive evidence that would either lead to such a calculation or could tell us with certainty that the risk is close to zero. If it isn't close to zero, I'd argue that we have to do everything we can to make sure it is. Because the insurance policy for a catastrophic damage happening at, say, 1% chance, is worth paying up to 1% of that catastrophic damage. My intuition is, it's way more than 1%.