In the technical summary from the NASA Jet Propulsion Laboratory based at the California Institute of Technology titled “Far northern permafrost may unleash Carbon within decades”,
Permafrost in the coldest northern Arctic — formerly thought to be at least temporarily shielded from global warming by its extreme environment — will thaw enough to become a permanent source of carbon to the atmosphere in this century, with the peak transition occurring in 40 to 60 years, according to a new NASA-led study.
The study calculated that as thawing continues, by the year 2300, total carbon emissions from this region will be 10 times as much as all human-produced fossil fuel emissions in 2016.
This paper, one of a long series of studies of the permafrost, including field assays of emissions using NASA and other aircraft, is titled:
|N. C. Parazoo, C. D. Koven, D. M. Lawrence, V. Romanovsky, C. E. Miller, “Detecting the permafrost carbon feedback: talik formation and increased cold-season respiration as precursors to sink-to-source transitions”, The Cryosphere, 12, 123-144, 2018.|
It is the first definitive example of a long held fear apparent to anyone familiar with climate science and who thinks deeply about it. While initial forcings off the climate optimum within which civilization has developed are caused completely and entirely by human emissions and actions, the effects of such emissions are, increasingly, amplified by natural forcings. The most direct one is from water vapor which, due to the Clausius-Clapeyron relation, and the fact that water vapor is itself a greenhouse gas, means, roughly, that for each part of warming due to CO2 emissions there’s a comparable part due to water vapor, resulting in a doubling of effect. As warming progresses, there are stores of organic and other Carbon which are frozen out of circulation and microbial activity because of temperature, principally in polar regions. As the Earth warms — and noting that polar regions, percentage-wise, warm more than temperate or tropical ones — these stores are challenged and, eventually, begin to ferment once more. This results in additional emissions of greenhouse gases, CO2 but sometimes CH4.
The implication of all this is that while, at present, we control nearly all of emissions and could, in principle, reverse them by our choice of energy and other deliberate designs, in time, an increasing fraction of emissions will come from natural sources, temperature dependent, over which we have no control whatsoever. Accordingly, if, someday, humanity wished to contain climate change by reducing emissions, while they could zero their own contributions, as time goes, there is no capability of zeroing these natural ones, because they respond to increased temperatures, and that is all. Even Solar Radiation Management, which, in my opinion, is a really bad idea, basically, in its designs, maintains temperatures at whatever they are, preventing increases. It does not cool Earth’s surface.
What’s worse is that even if humanity decided, because of the consequences, to try to scrub atmosphere of emissions, this project is only reasonable, if astronomically expensive, if human emissions are nearly zeroed. It is not possible to keep up with human emissions as they are at present. Human emissions cannot be zero because of those inherent in agriculture and food production, even if these were managed with vehicles and processes which themselves were zero emitting. Accordingly, to the degree to which natural sources increase and dominate, they might, at some point, render any project for direct capture of CO2 futile, closing the door on our climate fate, even if we wanted to spend huge amounts of financial and human capital to make it happen. This is well beyond the ability of any market incentives or technology or engineering to contain.
Thus, humanity could, in these circumstance, lose control. Certainly, such natural sources of emissions will make it increasingly more expensive to manage the effects of our emissions. At some point, we tip into a world which is hurling itself headlong into a climate destiny we cannot even imagine.
This is another, perhaps dominant reasons why keeping mean surface temperature changes to but +2 Celsius is so important.
We’re failing to do that.