5 ms·

Thawing permafrost, faster even than climate models predicted, could release so much carbon that feasible reductions in human carbon output will never be enough

by gxx 7y ago

Thawing permafrost, faster even than climate models predicted, could release so much carbon that feasible reductions in human carbon output will never be enough. [1] A similar worry is methane hydrates. [2] It seems that the only remaining hopes are rapid progress on carbon sequestration on a vast scale, or risky geoengineering. [1] https://www.pri.org/stories/2015-06-24/thawing-permafrost-could-have-catastrophic-consequences-scientists-warn https://www.pri.org/stories/2015-06-24/thawing-permafrost-co... [2] https://worldoceanreview.com/en/wor-1/energy/methane-hydrates/ https://worldoceanreview.com/en/wor-1/energy/methane-hydrate...

YjSe2GMQ 7y ago
It has to be geo-engineering. Where are you going to find energy to recapture carbon? Renewables and nuclear are a joke compared to carbon fuels: https://en.m.wikipedia.org/wiki/World_energy_consumption https://en.m.wikipedia.org/wiki/World_energy_consumption
kbutler 7y ago
"the idea of a ‘methane time bomb’ coming from warming sediments and permafrost is one thing we don't have to worry about in connection with global warming," "The researchers believe that soil and marine bacteria that feed on frozen fossil methane as it melts may explain its limited release, by preventing the methane from ever reaching the atmosphere." https://scripps.ucsd.edu/news/natural-methane-time-bomb-unlikely-wreak-climate-havoc https://scripps.ucsd.edu/news/natural-methane-time-bomb-unli...
- justin66 7y ago
  I think someone yesterday made a comment here about the value or otherwise of university press releases. That quote is pretty cringey when you think about the effect it will have on the average layperson's understanding of the problem. The abstract at Nature https://www.nature.com/articles/nature23316 https://www.nature.com/articles/nature23316 A longer explainer at Nature https://www.nature.com/articles/548403a https://www.nature.com/articles/548403a
  - kbutler 7y ago
    Nothing in the abstract or longer explainer contradicts those quotes, whether you consider them "cringey" or not. "The authors show that the 14C methane signature is relatively constant through this abrupt methane rise. They use a mass-balance calculation to show that this could not have happened if the rise was caused by emissions from geological sources, including hydrates" "Natural geological methane emissions are expected to have been higher during the past than in modern times12, and so the authors' estimate of emissions 12,000 years ago can be taken as an upper limit for today's climate system." The closest is the caveat that modern warming may go warmer, and thus further historical analysis and modeling is needed.
    - justin66 7y ago
      If you cannot see what I mean about how that quote was potentially deceptive because of its lack of context, I don't know what to say to you. (but I'm not one of those who downvoted you)
      - kbutler 7y ago
        Here's the conclusion from the paper itself: The differences between deglacial and modern warming preclude us from unequivocally ruling out the possibility of large-scale natural methane releases to the atmosphere from old carbon reservoirs in the future. Our results do, however, suggest that such releases are unlikely. This is consistent with recent atmospheric observations, which suggest that renewed growth of atmospheric CH4 since 2006 is not driven by emissions from the Arctic29, where the most vulnerable old carbon reservoirs are located today. Instead, our results support the hypothesis that any future increases in natural CH4 emissions to the atmosphere will be driven by contemporaneous sources such as wetlands. https://sci-hub.se/10.1038/nature23316 https://sci-hub.se/10.1038/nature23316 Another piece of context is that the "don't have to worry" quote was from "Scripps Oceanography geoscientist Jeff Severinghaus, who has been involved with this research project since 2000 and leads the study of ice core records at Scripps." He's in no way a global warming skeptic, but rather an advocate of decarbonization by 2050 to reduce anthropogenic warming, yet he says the sudden arctic methane release is something we don't have to worry about. There is always more context. Basically anything can be "potentially deceptive", but that does not mean that it is either deceptive or inaccurate. This appears to be a case where the university press release did a pretty good job of remaining true to the paper. It sounds like you are uncomfortable with the conclusion, rather than the summary of that conclusion.
- mirimir 7y ago
  This is just 2+ year old wishful thinking. As TFA discusses.
sebazzz 7y ago
Since methane is said to be a worst greenhouse gas compared to carbondioxide, is there at least a way to convert the methane in the atmosphere to CO2?
- justryry 7y ago
  It will break down on its own over a decade or so. Burning it off likely isn't feasible because its dissipating off the permafrost over huge areas.
- jfengel 7y ago
  Methane converts to CO2 on its own. That's why it receives less attention than carbon dioxide, even though it absorbs more infrared energy. The CO2 lasts effectively forever, and is more important for the long term change in the climate. It would be less-bad for the climate overall if we didn't get the extra temporary energy bump from methane, and it were "only" carbon dioxide directly. But no, there's no way to do that efficiently. The methane stores are spread over many thousands of square miles. It's just to diffuse to operate on directly.
sizzle 7y ago
https://en.m.wikipedia.org/wiki/Clathrate_gun_hypothesis https://en.m.wikipedia.org/wiki/Clathrate_gun_hypothesis The clathrate gun hypothesis is the popular name given to the idea that increases in sea temperatures or drops in sea levels can trigger a strong positive feedback effect on climate: first, warming causes a sudden release of methane from methane clathrate compounds buried in seabeds and seabed permafrost; second, because methane itself is a powerful greenhouse gas, temperatures rise further, and the cycle repeats. This runaway process, once started, could be as irreversible as the firing of a gun.
- GoodJokes 7y ago
  The clathrate gun hypothesis has been thoroughly debunked and is one of the few actual alarmist things out there that is not in line with current science.

by gxx 7y ago

YjSe2GMQ 7y ago

It has to be geo-engineering. Where are you going to find energy to recapture carbon? Renewables and nuclear are a joke compared to carbon fuels: https://en.m.wikipedia.org/wiki/World_energy_consumption https://en.m.wikipedia.org/wiki/World_energy_consumption

kbutler 7y ago

"the idea of a ‘methane time bomb’ coming from warming sediments and permafrost is one thing we don't have to worry about in connection with global warming," "The researchers believe that soil and marine bacteria that feed on frozen fossil methane as it melts may explain its limited release, by preventing the methane from ever reaching the atmosphere." https://scripps.ucsd.edu/news/natural-methane-time-bomb-unlikely-wreak-climate-havoc https://scripps.ucsd.edu/news/natural-methane-time-bomb-unli...

justin66 7y ago
I think someone yesterday made a comment here about the value or otherwise of university press releases. That quote is pretty cringey when you think about the effect it will have on the average layperson's understanding of the problem. The abstract at Nature https://www.nature.com/articles/nature23316 https://www.nature.com/articles/nature23316 A longer explainer at Nature https://www.nature.com/articles/548403a https://www.nature.com/articles/548403a
- kbutler 7y ago
  Nothing in the abstract or longer explainer contradicts those quotes, whether you consider them "cringey" or not. "The authors show that the 14C methane signature is relatively constant through this abrupt methane rise. They use a mass-balance calculation to show that this could not have happened if the rise was caused by emissions from geological sources, including hydrates" "Natural geological methane emissions are expected to have been higher during the past than in modern times12, and so the authors' estimate of emissions 12,000 years ago can be taken as an upper limit for today's climate system." The closest is the caveat that modern warming may go warmer, and thus further historical analysis and modeling is needed.
  - justin66 7y ago
    If you cannot see what I mean about how that quote was potentially deceptive because of its lack of context, I don't know what to say to you. (but I'm not one of those who downvoted you)
    - kbutler 7y ago
      Here's the conclusion from the paper itself: The differences between deglacial and modern warming preclude us from unequivocally ruling out the possibility of large-scale natural methane releases to the atmosphere from old carbon reservoirs in the future. Our results do, however, suggest that such releases are unlikely. This is consistent with recent atmospheric observations, which suggest that renewed growth of atmospheric CH4 since 2006 is not driven by emissions from the Arctic29, where the most vulnerable old carbon reservoirs are located today. Instead, our results support the hypothesis that any future increases in natural CH4 emissions to the atmosphere will be driven by contemporaneous sources such as wetlands. https://sci-hub.se/10.1038/nature23316 https://sci-hub.se/10.1038/nature23316 Another piece of context is that the "don't have to worry" quote was from "Scripps Oceanography geoscientist Jeff Severinghaus, who has been involved with this research project since 2000 and leads the study of ice core records at Scripps." He's in no way a global warming skeptic, but rather an advocate of decarbonization by 2050 to reduce anthropogenic warming, yet he says the sudden arctic methane release is something we don't have to worry about. There is always more context. Basically anything can be "potentially deceptive", but that does not mean that it is either deceptive or inaccurate. This appears to be a case where the university press release did a pretty good job of remaining true to the paper. It sounds like you are uncomfortable with the conclusion, rather than the summary of that conclusion.
mirimir 7y ago
This is just 2+ year old wishful thinking. As TFA discusses.

sebazzz 7y ago

Since methane is said to be a worst greenhouse gas compared to carbondioxide, is there at least a way to convert the methane in the atmosphere to CO2?

justryry 7y ago
It will break down on its own over a decade or so. Burning it off likely isn't feasible because its dissipating off the permafrost over huge areas.
jfengel 7y ago
Methane converts to CO2 on its own. That's why it receives less attention than carbon dioxide, even though it absorbs more infrared energy. The CO2 lasts effectively forever, and is more important for the long term change in the climate. It would be less-bad for the climate overall if we didn't get the extra temporary energy bump from methane, and it were "only" carbon dioxide directly. But no, there's no way to do that efficiently. The methane stores are spread over many thousands of square miles. It's just to diffuse to operate on directly.

sizzle 7y ago

https://en.m.wikipedia.org/wiki/Clathrate_gun_hypothesis https://en.m.wikipedia.org/wiki/Clathrate_gun_hypothesis The clathrate gun hypothesis is the popular name given to the idea that increases in sea temperatures or drops in sea levels can trigger a strong positive feedback effect on climate: first, warming causes a sudden release of methane from methane clathrate compounds buried in seabeds and seabed permafrost; second, because methane itself is a powerful greenhouse gas, temperatures rise further, and the cycle repeats. This runaway process, once started, could be as irreversible as the firing of a gun.

GoodJokes 7y ago
The clathrate gun hypothesis has been thoroughly debunked and is one of the few actual alarmist things out there that is not in line with current science.