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Peter Wadhams "Arctic Death Spiral" & Here
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It is estimated that another 1.9 trillion tonnes of carbon is stored in the ‘perma-frost’ [Science]. This permafrost has already started slowly melting due to enhanced global warming. Once on this path, the potential release of this extra CO2 to the atmosphere, is on a time-frame that is hard to calculate.
However, weighed on a scale of Billions of Tonnes of Carbon [Giga Tonnes or Gt C] it is easy to calculate, and once under way, it is virtually impossible to stop.
The weight reaches the top of this yellow shape at around 3 trill. tonnes of atmospheric carbon, or 1400 ppmv carbon [only].
IPCC estimates 1000 CO2-e is equal to a temperature rise by 2100 of 4-8°.
So the worst-case of perma-frost melt alone, dwarfs human emissions control and presages a climate holocaust.
The lined ‘grey’ areas in ‘Emissions’ and ‘Concentrations’ mathematically relate the former to the latter in forty theoretical steps downward & upwards from ‘the budget’ with concentrations at CAF 50-% for Budget + ‘feedback’ in each of the steps. So these are showing theoretically possible rates of negative & positive feedback from the process of carbon-cycling as a whole.
In the cause of UNFCCC-compliance, the world might theoretically hold to the ‘2016 4% Low’ Carbon Emissions Budget [as in the UK Climate Act]. However, positive feedback in the carbon cycle - e.g. from melting permafrost as suggested here - will release more CO2. The highest rate of CO2 emissions:concentration calculated here, shows a steady rate of acceleration across the Century ahead.
By mid-Century it is clear that, in this scenario, positive feedback is driving the system as a whole, driving to a point where ‘human-emission-control’ has become completely irrelevant.
There are two simple messages - we need to: -
1. Leave fossil carbon [oil, coal and gas] in the ground
2. Get on with human emissions control asap.
