biffvernon wrote:Aurora wrote:
Today, we get to cross the Rubicon.
Indeed. It's the sort of decision that leads us towards Hansen's nightmare:
“After the ice is gone, would Earth proceed to the Venus syndrome, a runaway greenhouse effect that would destroy all life on the planet, perhaps permanently? While that is difficult to say based on present information, I’ve come to conclude that if we burn all reserves of oil, gas and coal, there is a substantial chance we will initiate the runaway greenhouse. If we also burn the tar sands and oil shale, I believe the Venus syndrome is a dead certainty.”
James Hansen p236 Storms of my Grandchildren.
Fortunately, dead humans don't emit much CO2.
I think there is now a bettter-than-even chance that we're going to provoke the climate to switch to a new steady state. That means almost no permanent ice left on the surface within 200-300 years. To push it further than that would require even more industrial-scale human intervention, but that would require an industrial-scale human civilisation to still be in business. In reality, by the time the situation gets that bad there will already be very few humans left, compared to today.
We probably are indeed going to keep burning fossil fuels. We are also going to push the rest of the system to its limits wherever there is no easy alternative (as there was in the cases of CFCs and lead in petrol.) And that in turn means we are going to stretch the resources required to feed people - soil degradation, phosphorus depletion, pollution and depletion of groundwater required for agriculture, collapse of fisheries due to over-harvesting and other reasons...not to mention rapidly worsening climate chaos of the sort that is already impacting on food production.
In short, most of the human race is going to die of starvation, or associated wars and epidemics, long before we trigger a runaway greenhouse effect.
"We fail to mandate economic sanity because our brains are addled by....compassion." (Garrett Hardin)
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