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I remember reading (probably about 2 decades ago) that if we were to loose the permafrost the resulting release of CO2 would lead to runaway warming. I haven't

by josho 10y ago

I remember reading (probably about 2 decades ago) that if we were to loose the permafrost the resulting release of CO2 would lead to runaway warming. I haven't read that concern recently, so I'm hopeful that scientists no longer feel that way, but it is alarming to see this day has come.

eli_gottlieb 10y ago
Last I heard, scientists still feel that way, but they've gotten burned-out on trying to explain to the public exactly how doomed we actually are.
- kaybe 10y ago
  Yes, we still feel that way. It's not like we can do anything though.
  - chinathrow 10y ago
    How fast would the runaway happen?
    - taberiand 10y ago
      How fast is exponentially?
    - Spooky23 10y ago
      I'd argue that it's happening now. On February 17, it was 81F in my back porch in Albany, NY. That is an all time record. Right now, at 6PM EST, its 64F. It hasn't been below 20 in a week. Our average high is about 28F. We've had fewer snow events in the last 5 years than we had in any year in the 90s. The climate has already changed.
      - chc 10y ago
        The parent specifically asked about "the runaway," not merely climate change. The term "runaway" refers to a feedback effect, so that climate change breeds more climate change rather than relying on our carbon emissions to fuel it.
        M_Grey 10y ago
        "Now" still seems like a very good answer. I doubt that if we stopped emissions today, we'd see any positive changes for decades, and that's if we're very very lucky.
        mirimir 10y ago
        Yeah, "now" seems a good answer. A couple decades ago, I would have said "no clue, really". But now, it seems pretty clear. And yes, even without positive feedback, it would take several decades for forcing to relax after carbon emissions ceased. Which is very unlikely. So I really do think that it's time to consider active mitigation. But I'm not even very optimistic about that, given the likely positive feedbacks. Requisite mitigation requirements would also be going exponential. And where will the energy for that come from?
      - maxerickson 10y ago
        It's been warm here in Michigan also, but there were also record lows just 2 years ago, and while this year as been extraordinary, there are years in the late 1800s with big melt ups and so on. Which I'm just saying that it is difficult to take a season of weather and be sure it fits into a broader context. I'm arguing against drawing conclusions from short periods of observation.
      - IAmGraydon 10y ago
        Sorry...that's not what global warming does.
        Spooky23 10y ago
        Changes in weather patterns and seasonal events are absolutely a part of warming.
    - kaybe 10y ago
      I'm not sure I understand your question correctly. It is not a question of time but of system parameters. I just dug through the literature to get this right. The only study I found that actually modelled the feedback of the rising temperature due to emitted greenhouse gases (CO2 and CH4 - methane) on the permafrost says that any model they ran with a climate sensitivity above 3°C (how the system reacts to a doubling of CO2 or equivalent in the atmosphere [1]) produced a runaway effect, that is, atmospheric CO2 content keeps rising even if anthropogenic emissions stop in 2013 (which, as you know, they didn't). The current state on climate sensitivity is 3°C +-1.5°C. They estimated some parameters conservatively too. So it could be worse. Or better - there are still a lot of uncertainties. - The way carbon is released into the atmosphere can happen in different ways, and that can lead to different ratios of carbon in the air and other reservoirs like water or soil in bound form, as well as different ratios of methane and CO2 (they have vastly different atmospheric lifetimes and warming potential, so this matters). - The total amount of carbon stored in permafrost soils is unclear. Permafrost can be very thick and deep, and large areas are hard to access. edit: Estimations are that the reservoir holds about twice that of the current atmosphere. Some of that will definitely go into the ocean and biosphere, but it's still a lot. - Permafrost has a range of interesting behaviour during the freeze-thaw cycle (if you're interested, check it out, the features it produces are really neat). It is unclear how they change with temperature differences, and it influences the melting and release of carbon. - Other climate-related effects such as flooding, increased vegetation etc have an influence. How much? Hard to say. - Once the permafrost starts melting, carbon is released with a time delay, which is also not clear. .. and so on. Non-linear effects, effects highly dependent on topography, micro-climate, vegetation... very hard to model in a consistent way. So.. it might be wrong too. Let's hope so. The new balanced state will need years to centuries to be reached too, since thawing takes time. There is permafrost beneath the northern oceans. How? It's still there from the last ice age. A note on time: The numbers I found for increased temperature due to permafrost melting by 2100 are in the 0.1°C-0.7°C range [2]. So we're probably fine. The ones after us.. well. There are some other feedback mechanisms that still require research. It would be great if something there helped us.. or we are all horribly wrong. That would be brilliant. [1] https://en.wikipedia.org/wiki/Climate_sensitivity https://en.wikipedia.org/wiki/Climate_sensitivity [2] http://iopscience.iop.org/article/10.1088/1748-9326/9/8/085003/pdf http://iopscience.iop.org/article/10.1088/1748-9326/9/8/0850... http://www.nature.com/ngeo/journal/v5/n10/full/ngeo1573.html http://www.nature.com/ngeo/journal/v5/n10/full/ngeo1573.html This one is behind a paywall. :(
  - ced 10y ago
    Why not? Even assuming that the runaway is unstoppable, that's a fixed quantity. The final outcome will be runaway CO2 + everyone else's CO2 + our CO2 and we've got control over one of these terms.
    - georgemcbay 10y ago
      which term do "we" have control of exactly? also... define "we"? Speaking for myself, I live in a country in which my current elected leader claims that CO2-related climate change is a hoax perpetrated by the Chinese and who plans (essentially politically unopposed, at least for the next 2-4 years) to undo what little protection prior administrations have put into place to try to help. This does not give me a feeling of having any control whatsoever over the situation, but I'd love to hear what you think the realistic options are.
      - mirimir 10y ago
        It seems pretty clear that nobody is controlling any of it very well. And regarding the Chinese, I do appreciate the justice in cutting some GCC slack for less-industrialized nations. But since China has become such an effective economic competitor, that slack has become very spinnable.
      - ced 10y ago
        which term do "we" have control of exactly? also... define "we"? I initially wrote "I" instead of "we", and I should have stuck with that formulation. I have control over my own emissions. Climate change isn't a binary thing. The more CO2, the more people will (possibly) die. My choices still have an impact on the outcome, on top of whatever runaway effect there is (or isn't).
- tornadoboy55 10y ago
  Yeah, the common sentiment is 'the best time to take action was 40 years ago. The absolute limit was 20 years ago. There's no stopping it now, even if we reduce our emissions to zero. The latent emissions in the atmosphere will already bone us. I'm glad I live in the Netherlands. We're a very rich country, and we have been battling water for more than a thousand years as a people. Places like Bangladesh will be completely destroyed..
  - taberiand 10y ago
    I joke this is the real reason Elon Musk is digging tunnels and preparing to live in a Mars-like environment...
    - btilly 10y ago
      Why do you think that this is a joke? Elon has stated in all seriousness that he personally puts global warming at above a 1% chance of being a species-threatening event for us, and that we need to become a multi-planetary species to reduce the odds of extinction. He doesn't think that wiping out our species is a likely or even very probable. Just high enough that there is no better way that he can spend his time than trying to address and mitigate the problem.
      - taberiand 10y ago
        Because I don't really want to believe it's going to get that bad - I certainly won't be getting a place in the vaults.
      - kaybe 10y ago
        The thing is, even Earth at its worst is still by far the most habitable planet in the system. The biggest issue we have with climate change is that we and the biosphere are set up for it to be this way, and adaption is slow. We might have to move many cities and the agriculture, and somehow manage with a biosphere that takes many generations to adapt.
        10y ago
- vvanders 10y ago
  s3e3 of The Newsroom captured this brilliantly.
Diederich 10y ago
http://www.newsweek.com/2016/06/10/permafrost-greenhouse-gases-global-warming-465585.html http://www.newsweek.com/2016/06/10/permafrost-greenhouse-gas... https://en.wikipedia.org/wiki/Climate_change_feedback https://en.wikipedia.org/wiki/Climate_change_feedback 'runaway' is hard to predict, perhaps even hard to define, but we're getting a much better handle on climate change feedback mechanisms.
iaw 10y ago
> I haven't read that concern recently, so I'm hopeful that scientists no longer feel that way, but it is alarming to see this day has come. As others have said, this only became more proven. Even with a non-linearity at out-of-observation CO2 levels that causes temperatures to drop the resulting weather patterns will be... unpleasant.
- M_Grey 10y ago
  Don't worry, the continuous state of conflict and social/political upheaval will be a handy distraction from all of that.
deleted 10y ago
[deleted]

by josho 10y ago

eli_gottlieb 10y ago

Last I heard, scientists still feel that way, but they've gotten burned-out on trying to explain to the public exactly how doomed we actually are.

kaybe 10y ago
Yes, we still feel that way. It's not like we can do anything though.
- chinathrow 10y ago
  How fast would the runaway happen?
  - taberiand 10y ago
    How fast is exponentially?
  - Spooky23 10y ago
    I'd argue that it's happening now. On February 17, it was 81F in my back porch in Albany, NY. That is an all time record. Right now, at 6PM EST, its 64F. It hasn't been below 20 in a week. Our average high is about 28F. We've had fewer snow events in the last 5 years than we had in any year in the 90s. The climate has already changed.
    - chc 10y ago
      The parent specifically asked about "the runaway," not merely climate change. The term "runaway" refers to a feedback effect, so that climate change breeds more climate change rather than relying on our carbon emissions to fuel it.
      - M_Grey 10y ago
        "Now" still seems like a very good answer. I doubt that if we stopped emissions today, we'd see any positive changes for decades, and that's if we're very very lucky.
        mirimir 10y ago
        Yeah, "now" seems a good answer. A couple decades ago, I would have said "no clue, really". But now, it seems pretty clear. And yes, even without positive feedback, it would take several decades for forcing to relax after carbon emissions ceased. Which is very unlikely. So I really do think that it's time to consider active mitigation. But I'm not even very optimistic about that, given the likely positive feedbacks. Requisite mitigation requirements would also be going exponential. And where will the energy for that come from?
    - maxerickson 10y ago
      It's been warm here in Michigan also, but there were also record lows just 2 years ago, and while this year as been extraordinary, there are years in the late 1800s with big melt ups and so on. Which I'm just saying that it is difficult to take a season of weather and be sure it fits into a broader context. I'm arguing against drawing conclusions from short periods of observation.
    - IAmGraydon 10y ago
      Sorry...that's not what global warming does.
      - Spooky23 10y ago
        Changes in weather patterns and seasonal events are absolutely a part of warming.
  - kaybe 10y ago
    I'm not sure I understand your question correctly. It is not a question of time but of system parameters. I just dug through the literature to get this right. The only study I found that actually modelled the feedback of the rising temperature due to emitted greenhouse gases (CO2 and CH4 - methane) on the permafrost says that any model they ran with a climate sensitivity above 3°C (how the system reacts to a doubling of CO2 or equivalent in the atmosphere [1]) produced a runaway effect, that is, atmospheric CO2 content keeps rising even if anthropogenic emissions stop in 2013 (which, as you know, they didn't). The current state on climate sensitivity is 3°C +-1.5°C. They estimated some parameters conservatively too. So it could be worse. Or better - there are still a lot of uncertainties. - The way carbon is released into the atmosphere can happen in different ways, and that can lead to different ratios of carbon in the air and other reservoirs like water or soil in bound form, as well as different ratios of methane and CO2 (they have vastly different atmospheric lifetimes and warming potential, so this matters). - The total amount of carbon stored in permafrost soils is unclear. Permafrost can be very thick and deep, and large areas are hard to access. edit: Estimations are that the reservoir holds about twice that of the current atmosphere. Some of that will definitely go into the ocean and biosphere, but it's still a lot. - Permafrost has a range of interesting behaviour during the freeze-thaw cycle (if you're interested, check it out, the features it produces are really neat). It is unclear how they change with temperature differences, and it influences the melting and release of carbon. - Other climate-related effects such as flooding, increased vegetation etc have an influence. How much? Hard to say. - Once the permafrost starts melting, carbon is released with a time delay, which is also not clear. .. and so on. Non-linear effects, effects highly dependent on topography, micro-climate, vegetation... very hard to model in a consistent way. So.. it might be wrong too. Let's hope so. The new balanced state will need years to centuries to be reached too, since thawing takes time. There is permafrost beneath the northern oceans. How? It's still there from the last ice age. A note on time: The numbers I found for increased temperature due to permafrost melting by 2100 are in the 0.1°C-0.7°C range [2]. So we're probably fine. The ones after us.. well. There are some other feedback mechanisms that still require research. It would be great if something there helped us.. or we are all horribly wrong. That would be brilliant. [1] https://en.wikipedia.org/wiki/Climate_sensitivity https://en.wikipedia.org/wiki/Climate_sensitivity [2] http://iopscience.iop.org/article/10.1088/1748-9326/9/8/085003/pdf http://iopscience.iop.org/article/10.1088/1748-9326/9/8/0850... http://www.nature.com/ngeo/journal/v5/n10/full/ngeo1573.html http://www.nature.com/ngeo/journal/v5/n10/full/ngeo1573.html This one is behind a paywall. :(
- ced 10y ago
  Why not? Even assuming that the runaway is unstoppable, that's a fixed quantity. The final outcome will be runaway CO2 + everyone else's CO2 + our CO2 and we've got control over one of these terms.
  - georgemcbay 10y ago
    which term do "we" have control of exactly? also... define "we"? Speaking for myself, I live in a country in which my current elected leader claims that CO2-related climate change is a hoax perpetrated by the Chinese and who plans (essentially politically unopposed, at least for the next 2-4 years) to undo what little protection prior administrations have put into place to try to help. This does not give me a feeling of having any control whatsoever over the situation, but I'd love to hear what you think the realistic options are.
    - mirimir 10y ago
      It seems pretty clear that nobody is controlling any of it very well. And regarding the Chinese, I do appreciate the justice in cutting some GCC slack for less-industrialized nations. But since China has become such an effective economic competitor, that slack has become very spinnable.
    - ced 10y ago
      which term do "we" have control of exactly? also... define "we"? I initially wrote "I" instead of "we", and I should have stuck with that formulation. I have control over my own emissions. Climate change isn't a binary thing. The more CO2, the more people will (possibly) die. My choices still have an impact on the outcome, on top of whatever runaway effect there is (or isn't).
tornadoboy55 10y ago
Yeah, the common sentiment is 'the best time to take action was 40 years ago. The absolute limit was 20 years ago. There's no stopping it now, even if we reduce our emissions to zero. The latent emissions in the atmosphere will already bone us. I'm glad I live in the Netherlands. We're a very rich country, and we have been battling water for more than a thousand years as a people. Places like Bangladesh will be completely destroyed..
- taberiand 10y ago
  I joke this is the real reason Elon Musk is digging tunnels and preparing to live in a Mars-like environment...
  - btilly 10y ago
    Why do you think that this is a joke? Elon has stated in all seriousness that he personally puts global warming at above a 1% chance of being a species-threatening event for us, and that we need to become a multi-planetary species to reduce the odds of extinction. He doesn't think that wiping out our species is a likely or even very probable. Just high enough that there is no better way that he can spend his time than trying to address and mitigate the problem.
    - taberiand 10y ago
      Because I don't really want to believe it's going to get that bad - I certainly won't be getting a place in the vaults.
    - kaybe 10y ago
      The thing is, even Earth at its worst is still by far the most habitable planet in the system. The biggest issue we have with climate change is that we and the biosphere are set up for it to be this way, and adaption is slow. We might have to move many cities and the agriculture, and somehow manage with a biosphere that takes many generations to adapt.
      - 10y ago
vvanders 10y ago
s3e3 of The Newsroom captured this brilliantly.

Diederich 10y ago

http://www.newsweek.com/2016/06/10/permafrost-greenhouse-gases-global-warming-465585.html http://www.newsweek.com/2016/06/10/permafrost-greenhouse-gas... https://en.wikipedia.org/wiki/Climate_change_feedback https://en.wikipedia.org/wiki/Climate_change_feedback 'runaway' is hard to predict, perhaps even hard to define, but we're getting a much better handle on climate change feedback mechanisms.

iaw 10y ago

> I haven't read that concern recently, so I'm hopeful that scientists no longer feel that way, but it is alarming to see this day has come. As others have said, this only became more proven. Even with a non-linearity at out-of-observation CO2 levels that causes temperatures to drop the resulting weather patterns will be... unpleasant.

M_Grey 10y ago
Don't worry, the continuous state of conflict and social/political upheaval will be a handy distraction from all of that.

deleted 10y ago

[deleted]