Support the Arctic Sea Ice Forum and Blog

Author Topic: Melting Arctic an "economic time bomb"  (Read 63253 times)

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #50 on: July 26, 2013, 07:24:49 PM »
Dorlomin


Didn't Shakhova present figures on the rapid increase of bottom temperatures in the ESAS? I don't have them in front of me but as I recall it was a significant number (though less than 7C)


Terry

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #51 on: July 26, 2013, 07:25:35 PM »
Is there a way to date the hydrates and if so has it been done?

If Arctic hydrates are exclusively younger than Eemian times it indicates that whatever clathrates had formed earlier have outgassed during the Eemian & will do so again as we reach for Eemian temperatures. Since we're heating things up much more rapidly than ever before it seems as though what could have been a measured release in the past might accelerate and cause a feedback allowing the 20 year effects of CH4 to cause ever more rapid outgassing.

I'm not sure about dating them - if there is any isotopic signature or similar that could do the trick. However - it seems possible to infer for some locations at least whether or not the activity is brand new or has been ongoing at at least some level for a long time:

http://www.sciencedaily.com/releases/2012/09/120924144054.htm

If there are the associated carbonate deposits, that seems to provide an indication of the length of activity - and so does the presence of hydrogen sulphide within the water, given that this states the growth of bacterial colonies to be rather slow in this environment (makes sense if you look at just how low the solubility of methane in water is and the low temperatures - around 40mg/l if memory serves)

I haven't seen anything commenting on the presence of either indicator on the ESAS sites to date. It wouldn't rule out a significant increase in activity, but it would help identify if at least some level of activity had been ongoing for a long time (as off Svalbard in deeper water).

I'd like to think it ought to be possible to refine the results of the Svalbard expedition to try to infer recent history in terms of changing release of methane with more data, ie if hydrogen sulphide concentration is low vs methane, it would indicate a recent increase in methane release (I can see this would have limited value in regions where the water is saturated with either gas).

My understanding is that the clathrate deposits on the ESAS are up to 200m thick (substantially thicker than the typical water depth) - perhaps another way to approach the question of how old they might be is to try to come up with some estimate of how fast they are formed and grew to such thickness? Is 1cm every 5 years a likely rate of growth of such a deposit? (200m in 100,000 years - feels a bit faster to me but I really don't know)

I'm personally convinced that Shakhova and Semiletov were told at some point to keep quiet about the results of their 2011 cruise. Hope this doesn't require me to don the tinfoil chapeau.

Best wear it. After all, if you'd claimed certain western governments were spying on virtually every online means of communication and mass harvesting communications with automated algorithms and even in some cases storing total regional internet activity for limited durations - you'd have been told to wear it (pre Snowden).

Whatever the denier types and obsessive mainstreamers (and the two groups are rapidly moving closer together as far as I can see - mainstreamers being more vocal in opposing scenarios at the worse end of the spectrum and deniers gradually falling back on IPCC statements to try to defend their positions) think, I think keeping an open mind is really rather important in these matters. While nobody can rule a catastrophic near future release of methane probable - key experts in that area seem unable to rule it out or even to say they're confident it is very unlikely.

Hopefully Semiletov and Shakhova will release more papers soon - that seems to be the best place to look for what they have to say.

I think it should be kept in mind that we live on a planet that is capable of profound and rapid changes - a complex machine that we are nowhere near understanding.

One would think there would be lessons for the deniers and mainstream obsessives in just how fast the sea ice is changing versus expectations - but no - rinse and repeat, it seems.

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #52 on: July 26, 2013, 07:32:57 PM »
Didn't Shakhova present figures on the rapid increase of bottom temperatures in the ESAS? I don't have them in front of me but as I recall it was a significant number (though less than 7C)

Quoting from the Semiletov paper "The degradation of submarine permafrost":

Quote
It is significant that no submarine permafrost was found along the entire borehole to the sediment depth of 53 m. The minimum temperature of –0.9°C was registered in the upper layer of sediments in thermal equilibrium with the nearbottom water. Downwards through the core, the temperature increased to –0.3°C.

More tellingly, with references to warmer water run off from the warming adjacent land mass and wind driven mixing (in an area now increasingly free from sea ice):

Quote
Note that the temperature of bottom sediments in the Dmitrii Laptev Strait increases to 3°C in summer owing to the wind induced mixing of warm and desalinated waters of the Lena River flow to the bottom [13], which causes the formation of annual average temperatures of about 0°C for the near bottom waters and permafrost in this area. Note that the submarine permafrost is naturally salinized to a degree that determines its thawing at negative temperatures (depending on the mineralization of sediments). Under the conditions of the observed abnormal warming of the East Siberian shelf, the acceleration of thawing of the upper layer of submarine permafrost and an increase of bottom erosion are inevitable.

Oddly enough, I'd rather take Shakhova and Semiletov seriously than random internet pundits unable to cite anything of substance.

[EDIT] And before we get anyone coming up with the auto-deny argument that there's no way to get heat deeper into the seabed:

Quote
In some oceanographic sections, a number of plumes over 100 m in diameter were joined into a multirooted enormous plume over 1000 m in diameter (Fig. 2), which exceeds greatly the dimensions of plumes registered formerly in the Sea of Okhotsk and in other areas of the World
Ocean where the typical plume diameter usually varied from a few meters to tens of meters. The integrated hydroacoustic and geophysical surveys permitted us to identify the plume roots going deep into the 15 to 20km layer of the ESS sediments, which are enriched in organic matter

I would imagine that once the escaping gas forces migration pathways erosion from escaping gas both widens the pathways (permits more gas to escape) - and allows water to come down into the seabed to transport heat deeper.

There really is a lot more known about this than some people seem to realise - and unfortunately we don't have a lot of good news yet, excepting the identification that the Svalbard deep water deposits have been releasing methane since before the industrial revolution (and deeper water is a whole other kettle of fish as more of the automatically presented denying arguments are valid there).

mabs

  • New ice
  • Posts: 28
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #53 on: July 26, 2013, 08:12:47 PM »
Prof. Peter Wadhams, one of the authors of the study, has posted a reply to the recent criticism of the study's findings in the Washington Post and other publications. I thought it would be useful to add it to the conversation.

http://www.cam.ac.uk/research/discussion/a-response-to-methane-mischief-misleading-commentary-published-in-nature

I'm going to highlight some parts in the reply I thought to be particularly interesting, but the whole post is worth reading.

Quote
The 2008 US Climate Change Science Program report  needs to be seen in this context. Equally, David Archer’s 2010 comment that “so far no one has seen or proposed a mechanism to make that (a catastrophic methane release) happen” was not informed by the Semiletov/Shakhova field experiments and the mechanism described above. Carolyn Rupple’s review of 2011 equally does not reflect awareness of this new mechanism.

The mechanism he is talking about:
Quote
What is happening is that the summer sea ice now retreats so far, and for so long each summer, that there is a substantial ice-free season over the Siberian shelf, sufficient for solar irradiance to warm the surface water by a significant amount – up to 7C according to satellite data. That warming extends the 50 m or so to the seabed because we are dealing with only a polar surface water layer here (over the shelves the Arctic Ocean structure is one-layer rather than three layers)  and the surface warming is mixed down by wave-induced mixing because the extensive open water permits large fetches.  So long as some ice persisted on the shelf, the water mass was held to about 0C in summer because any further heat content in the water column was used for melting the ice underside. But once the ice disappears, as it has done, the temperature of the water can rise significantly, and the heat content reaching the seabed can melt the frozen sediments at a rate that was never before possible.

I'm finding the discussion on this thread to be very informative. I do not yet have anything more to add here (trying to catch up), but I want to thank everyone for their contributions here. I'm learning a lot about this from all of you.
No god and no religion can survive ridicule. No church, no nobility, no royalty or other fraud, can face ridicule in a fair field and live.
-Mark Twain, Notebook, 1888

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #54 on: July 26, 2013, 11:48:48 PM »
I for one am very glad that we're having this conversation. I've never been able to convince myself that there is no danger from this quarter & I've never been able to believe that it's inevitable (probably because of the immensity and finality)


I'd followed S&S's arguments carefully as they were being made, then waited & waited & waited for the publication of their findings. The long "vacation" after their return seemed very odd.


If at great expense and with much fanfare we had sent out a crew to investigate a killer asteroid that was threatening humanity, and when they returned they said that it was on course and coming fast - BTW we're going to be taking a well earned rest and won't be able to fill you in on the details until we're back to work again. After their time out they talk of the danger that comets pose and how these occur in natural cycles, but don't get back to what they discovered on their cruise.


At some point you have to wonder just what they did find. Just how soon the asteroid will be arriving and why, if it's going to be a near miss, they aren't shouting it from the rooftops.


Almost any response other than the non-response that we got would have been less alarming. I don't lean towards conspiracies, but it seems to me as though the powers that be have decided that whatever S&S found, it was worse than or confirmed their speculations before the cruise.


Terry

wili

  • Young ice
  • Posts: 3342
    • View Profile
  • Liked: 602
  • Likes Given: 409
Re: Melting Arctic an "economic time bomb"
« Reply #55 on: July 26, 2013, 11:57:25 PM »
Terry, nicely put.

illigitimi non carborundum!
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #56 on: July 27, 2013, 02:14:05 AM »
I've speculated that a large methane release will have an excess warming effect compared to the usual GWP multipliers used over various timescales due to the breakdown mechanism being overwhelmed. This paper would appear to confirm that that is reasonable speculation (and to potentially put some attempts at values to the effects):

http://www.atmos-chem-phys-discuss.net/11/9057/2011/acpd-11-9057-2011.pdf

Worse though - it looks as though a large methane release could also unhelpfully impact cloud albedo, if I understand it right (and speculatively perhaps even rainfall?).

I'll quote only the conclusion here (I haven't read it all in detail yet, and am unsure yet if it's fully within my reach):

Quote
Using a combination of atmospheric models, we show that the total radiative forcing
associated with a large methane increase may be around twice as large as the direct greenhouse effect enhancement of the added methane. The main indirect forcing component is the decrease in cloud droplet number concentration, cloud fraction and condensate amount caused by a strong decrease in OH concentrations. We also investigated the effect of doubling atmospheric NOx levels in order to regenerate OH, but found this hypothetical drastic geoengineering technique to be ineffective.

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #57 on: July 27, 2013, 02:23:28 AM »
At some point you have to wonder just what they did find. Just how soon the asteroid will be arriving and why, if it's going to be a near miss, they aren't shouting it from the rooftops.

It seems to me that the best place to listen to them is what they write in the published papers? Media quotes did an about turn immediately followed by dead silence - but some of the things in the papers don't seem to be pulling many punches.

Certainly, I'm leaning towards the "greater concern" side of the scale based on what I've seen - but I do need to try to track down more of their recent stuff to see what else is in it. It's perfectly reasonable to speculate that some degree of methane release may well have been ongoing from the ESAS for millennia but I think it's borderline absurd for people to argue regional warming due to climate change isn't going to have a serious impact (and going by the language in the published papers, potentially a profound impact - although no firm conclusions are stated yet - and may never be).

The only final resolution to this argument might well be if we start to get large eruptions New Zealand crater style from there - given the time it takes gases to mix globally, and the response time of the system to start to soak up the extra heat, we'd get at least a little "I told you so" time - assuming there weren't other simultaneous overbearing factors acting by then (a rather tenuous assumption).

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #58 on: July 27, 2013, 06:30:58 AM »
This is highly speculative on my part.

I noted a commentator pointing out that methane clathrate is buoyant in water (lighter than the water) and would therefore tend to float.

It seems possible to me that this is enough to provide a mechanism for abrupt and large releases without the need to invoke tectonic activity or submarine landslides or other external mechanical rupturing of containment. It should be noted that free methane gas is also trapped with the clathrate - made very clear in the paper I keep quoting from.

Therefore the mechanism I suggest could work like this:

  • Warming and destabilisation of the upper portion of a concentrated large clathrate deposit, accompanied by thawing where containment was done by frozen permafrost.
  • Methane gas under pressure is able to escape, forcing open migration pathways
  • The escaping gas erode and enlarges the migration pathways, carrying away sediment (or other mass pinning down the main deposit)
  • With pinning mass removed, the main portion of the clathrate deposit is free to float up, leaving a large crater on the seabed
  • Result - large and abrupt release of methane to the atmosphere, without an external event forcing matters (eg submarine landslide or tectonic activity)

I realise there are a few details to increase credibility, that I don't know offhand - for example I don't know how concentrated the clathrate deposits are and to what extend they would have overall buoyancy in large volumes. Still - this would seem to be a route to accelerating release and to getting deeper into the clathrate layer (200m thick in the case of ESAS) than just relying on wind driven mixing and warmer water run off.

Any thoughts? It's just an off the cuff idea... so please nobody claim I'm saying it's a fact.

Apocalypse4Real

  • Frazil ice
  • Posts: 370
    • View Profile
  • Liked: 3
  • Likes Given: 1
Re: Melting Arctic an "economic time bomb"
« Reply #59 on: July 27, 2013, 06:58:43 AM »
I think two monthly average images of AIRS CH4 concentration at 400 mb/hPa create the picture of release and change in concentration in less than a decade.

First image, January 2003.

Second image, January 2012.

I think the change is obvious, in some areas in red, the concentration in 2012 was over 1900 ppbv.

It is also ...... real satellite data.
« Last Edit: July 27, 2013, 07:20:27 AM by Apocalypse4Real »

Apocalypse4Real

  • Frazil ice
  • Posts: 370
    • View Profile
  • Liked: 3
  • Likes Given: 1
Re: Melting Arctic an "economic time bomb"
« Reply #60 on: July 27, 2013, 07:44:08 AM »
Four more METOP A IASI satellite views of CH4 concentration for November 1-10 at 600 mb.

First 2008,
Second 2009,
Third 2011,
Fourth 2012,

Note: This scale is higher than the AIRS - dark red is above 1920 ppbv, not 1870.

While we can observe a major jump in 2011, when Semelitov and Shakhova saw the higher methane release, we can also note that this is also part of a continuing slower increase in hemispheric CH4 over the last decade.

Ice loss, refreeze, warmer waters, seem to be contributing factors.
« Last Edit: July 27, 2013, 05:44:05 PM by Apocalypse4Real »

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #61 on: July 29, 2013, 05:15:47 PM »
Hot off the presses, apparently:

http://www.livescience.com/38488-earthquakes-trigger-methane-release.html

NB not the ESAS, and not a multi-gigatonne event

ritter

  • Grease ice
  • Posts: 573
    • View Profile
  • Liked: 24
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #62 on: July 29, 2013, 06:23:34 PM »
First image, January 2003.

Second image, January 2012.

I think the change is obvious, in some areas in red, the concentration in 2012 was over 1900 ppbv.

Bleeding methane, so to speak.

I have wondered what those would show if the scale was changed to something above 1900 ppbv.

dorlomin

  • New ice
  • Posts: 82
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #63 on: July 29, 2013, 11:57:44 PM »
Four more METOP A IASI satellite views of CH4 concentration for November 1-10 at 600 mb.

Ice loss, refreeze, warmer waters, seem to be contributing factors.
Zero evidence for an increasing contribution from the East Siberian Ice Shelf.

All it shows is that global CH4 levels are rising and that in November high latitude regions have a high concentration of CH4.
Take it for granted you are wrong.
Just try to work out what about and why.

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #64 on: July 30, 2013, 08:44:57 AM »

Vergent seems to have confirmed that sea water density follows fresh water in having it's greatest density at 3.98C for a particular salinity.

If Dr. Wadhams is correct and there is no thermohaline layering over the ESAS this implies that whenever ice cover is not present the most dense water at ~4C will sink to the bottom and will be melting the now permeable ice cap with convection currents refreshing these warm waters even without mixing due to wave action.


This additional warming increases the likelihood of sudden failure of the cap shortly after the summer ice free periods began. I think the clock is ticking.


Terry

CraigsIsland

  • Frazil ice
  • Posts: 206
    • View Profile
  • Liked: 4
  • Likes Given: 25
Re: Melting Arctic an "economic time bomb"
« Reply #65 on: July 30, 2013, 09:38:23 AM »

Vergent seems to have confirmed that sea water density follows fresh water in having it's greatest density at 3.98C for a particular salinity.

If Dr. Wadhams is correct and there is no thermohaline layering over the ESAS this implies that whenever ice cover is not present the most dense water at ~4C will sink to the bottom and will be melting the now permeable ice cap with convection currents refreshing these warm waters even without mixing due to wave action.


This additional warming increases the likelihood of sudden failure of the cap shortly after the summer ice free periods began. I think the clock is ticking.


Terry

Indeed that clock is ticking. The probability is going to increase as the ice cover retreats more, or as I have learned in recent days, seismic activity. Amazing how much I took this nice California weather for granted.

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #66 on: July 30, 2013, 09:51:49 AM »

Vergent seems to have confirmed that sea water density follows fresh water in having it's greatest density at 3.98C for a particular salinity.


I don't know how that came up, but it is wrong. At sea salinities, density is highest at freezing point (~ -2 oC).

a google answer

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #67 on: July 30, 2013, 11:29:28 AM »
This additional warming increases the likelihood of sudden failure of the cap shortly after the summer ice free periods began. I think the clock is ticking.

Inasmuch as one requires significant amounts of methane to be released to initiate feedback where further methane release becomes strictly self sustaining (as opposed to just self amplifying to a more limited extent), and it will still take at least some time to complete destablisation of the clathrates - I'd be surprised if we didn't get years of warning as the situation worsened. I don't see it as being a literally overnight process. Even if some gigatonnes were dumped into the atmosphere truly abruptly (seems possible) it would still take some time for the climate and global average temperatures to respond significantly.

That's all assuming that by the time it starts to go in a bigger way that modern civilisation is still operational and the satellites are all still up there beaming data down to people receiving it on the ground. That isn't necessarily a safe assumption.

At the indeterminate point in the future at which we lose the ability to keep an eye on the rest of the world and to measure and observe big picture changes, we will all (at best) be passive actors in a much smaller world only seeing a tiny fragment of the puzzle. Any one left around by that time won't have the capability to know what's happening, even if they have the knowledge and intelligence to understand it (if given the data).

Another minor point - I don't know why people keep making the point that poorer less developed nations will bear the brunt of the costs (as in this study). That isn't really how it seems to me to play out - they pay the most in human lives, the developed world has more to lose in financial and infrastructure terms. That applying for the earlier stages at least - later - it might be much of a muchness.

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #68 on: July 30, 2013, 12:07:48 PM »

Vergent seems to have confirmed that sea water density follows fresh water in having it's greatest density at 3.98C for a particular salinity.


I don't know how that came up, but it is wrong. At sea salinities, density is highest at freezing point (~ -2 oC).

a google answer


Thanks so much.


I'd been looking for verification earlier & may have misunderstood the response. Are you aware of a chart showing the change in maximum density at different salinity levels?
Terry

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #69 on: July 31, 2013, 03:36:58 AM »
Wipneus


Your calculations are correct for almost all of the Arctic Ocean. The ESAS however is different because of the low salinity.


The density curve of sea water maximizes at the freezing point whenever salt content is over 24.7 psu. Fresh water however has it's maximum density at 3.98C and this drops to ~-1C at 24.7 psu linearly.


While HYCOM only shows psu levels down to 26, other literature records the lower levels found in the ESAS.


Where the psu is less than 24.7 warm dense waters will sink through lighter cooler water and finally give up their heat to the frozen cap below. A convection current will be constantly replenishing the warmer water so rapid melting should be occurring.


The temperature that the convection is operating at will be determined by the psu of the water. The ESAS is at it's freshest in Summer corresponding to the times that it's been free of ice in recent years.
http://books.google.ca/books?id=aHnSiz5iV1YC&pg=PA180&lpg=PA180&dq=freezing+point+at+24.7+psu&source=bl&ots=FCIb3XM0nC&sig=Hu_qY0VP7qYDkyjByiMAzwMuCJo&hl=en&sa=X&ei=NGb4UazgC7Lk4AP2q4CABg&ved=0CFIQ6AEwCA#v=onepage&q=freezing%20point%20at%2024.7%20psu&f=false



ftp://hjalmar.npolar.no/ASOF/library/pdf/Steele_GRL.pdf



I'm not sure how important this convection is to the longevity of the frozen barrier, but it has to be having some negative effects.
Terry

Apocalypse4Real

  • Frazil ice
  • Posts: 370
    • View Profile
  • Liked: 3
  • Likes Given: 1
Re: Melting Arctic an "economic time bomb"
« Reply #70 on: July 31, 2013, 06:04:19 AM »
Speaking of more significant methane release, it seems that the Middle East or Africa hit a high concentration July 29, 2013 12-24 hr.

Image of high concentration attached.

A4R

anonymous

  • Guest
Re: Melting Arctic an "economic time bomb"
« Reply #71 on: July 31, 2013, 01:45:54 PM »
Despite all the debunking going on at NYT, WP and Twitter, the Guardian keeps the discussion lively, subline: Critics of new Nature paper on costs of Arctic warming ignore latest science on permafrost methane at everyone's peril

Very interesting!

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #72 on: July 31, 2013, 07:36:08 PM »
A***
Thanks for the link, It's a very interesting conversation that's going on.


Terry

wili

  • Young ice
  • Posts: 3342
    • View Profile
  • Liked: 602
  • Likes Given: 409
Re: Melting Arctic an "economic time bomb"
« Reply #73 on: July 31, 2013, 07:56:24 PM »
Yes, good link, arctico. These seem to be two of the 'take-away' paragraphs relevant to some points brought up in the current discussion here:

Quote
Dr Gavin Schmidt, climate modeller at NASA, was also cited claiming lack of evidence from ice cores of previous catastrophic methane pulses in the Earth's history in the Early Holocene or Eamian, when Arctic temperatures were warmer than today. But the blanket references to the past may well be irrelevant. In the Early Holocene, the ESAS was not an underwater shelf but a frozen landmass, illustrating the pointlessness of this past analogy with contemporary conditions.


 Schmidt also overlooked other issues - such as new research showing that the warm, Eamian interglacial period some 130,000 years ago should not be used as a model for today's climate due to fundamental differences in the development of the Arctic ocean. Ice core methane records are also too short to reach back to the entire Cenozoic - another reason suggesting lack of past evidence is no basis for present complacency; and even Prof Archer himself recognizes that ice cores will not necessarily capture a past catastrophic methane release due to fern diffusion.


"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #74 on: July 31, 2013, 08:10:26 PM »
What is "fern diffusion"?
Terry

ritter

  • Grease ice
  • Posts: 573
    • View Profile
  • Liked: 24
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #75 on: July 31, 2013, 08:16:34 PM »
What is "fern diffusion"?
Terry

I believe it is a typo. Google "firn diffusion". Firn is a type of snow. Learned something new today (again)! http://en.wikipedia.org/wiki/Firn

hank

  • New ice
  • Posts: 1
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #76 on: August 01, 2013, 08:17:13 PM »
For CCGWebmaster --- where are you getting the long detailed quotes?

From this?  http://link.springer.com/article/10.1134%2FS1028334X12080144

Doklady Earth Sciences
September 2012, Volume 446, Issue 1, pp 1132-1137
The degradation of submarine permafrost and the destruction of hydrates on the shelf of east arctic seas as a potential cause of the “Methane Catastrophe”: some results of integrated studies in 2011

Purchase on Springer.com  $39.95 / €34.95 / £29.95
ABSTRACT:
On the basis of the analysis of published data and in the course of the authors’ long-term geochemical and acoustic surveys performed in 1995–2011 on the East Siberian shelf (ESS) and aimed to research the role of the Arctic shelf in the processes of massive methane outbursts into the Earth’s atmosphere, some crucially new results were obtained. A number of hypotheses were proposed concerning the qualitative and quantitative characterization of the scale of this phenomenon. The ESS is a powerful supplier of methane to the atmosphere owing to the continued degradation of the submarine permafrost, which causes the destruction of gas hydrates. The emission of methane in several areas of the ESS is massive to the extent that growth in the methane concentrations in the atmosphere to values capable of causing a considerable and even catastrophic warning on the Earth is possible. The seismic data were compared to those of the drilling from ice performed first by the authors in 2011 in the southeastern part of the Laptev Sea to a depth of 65 m from the ice surface. This made it possible to reveal some new factors explaining the observed massive methane bursts out of the bottom sediments.
Original Russian Text © V.I. Sergienko, L.I. Lobkovskii, I.P. Semiletov, O.V. Dudarev, N.N. Dmitrievskii, N.E. Shakhova, N.N. Romanovskii, D.A. Kosmach, D.N. Nikol’skii, S.L. Nikiforov, A.S. Salomatin, R.A. Anan’ev, A.G. Roslyakov, A.N. Salyuk, V.V. Karnaukh, D.B. Chernykh, V.E. Tumskoi, V.I. Yusupov, A.V. Kurilenko, E.M. Chuvilin, B.A. Bukhanov, 2012, published in Doklady Akademii Nauk, 2012, Vol. 446, No. 3, pp. 330–335.

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #77 on: August 01, 2013, 08:35:48 PM »
For CCGWebmaster --- where are you getting the long detailed quotes?

From this?  http://link.springer.com/article/10.1134%2FS1028334X12080144

Doklady Earth Sciences
September 2012, Volume 446, Issue 1, pp 1132-1137
The degradation of submarine permafrost and the destruction of hydrates on the shelf of east arctic seas as a potential cause of the “Methane Catastrophe”: some results of integrated studies in 2011

Yep, that's the one. I'm digging (ie scavenging) to try to find other relevant papers - so I'm not just quoting from a single paper. So far I looked at one on the Kara sea that appears to strongly support what Shakova and Semiletov have said, where they aren't named as authors - ie no direct input (though it cites some of their papers). That's important as it broadens the scientific consensus.

I vaguely recall hearing on the grapevine that we should expect a big paper from Semiletov and Shakhova within the next year or two - and the suggestion that they may have actually held onto a lot of their findings and conclusions to present together (presumably after acquiring a high degree of certainty - as they have generally been rather conservative and restrained(!) in their statements. If that proves correct, we may only have received teasers so far...

Either way, this is a space to watch.

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #78 on: August 05, 2013, 10:36:26 AM »
Another decent article by Nafeez Ahmed on the Guardian (I noted one issue, though it didn't relate to methane) - this presenting counter arguments to a lot of the oft trotted out arguments against the risks.

http://www.theguardian.com/environment/earth-insight/2013/aug/05/7-facts-need-to-know-arctic-methane-time-bomb

EDIT Apparently the issue is a non issue.
« Last Edit: August 05, 2013, 12:01:22 PM by ccgwebmaster »

Apocalypse4Real

  • Frazil ice
  • Posts: 370
    • View Profile
  • Liked: 3
  • Likes Given: 1
Re: Melting Arctic an "economic time bomb"
« Reply #79 on: August 05, 2013, 04:59:29 PM »
ccg,

Thanks for your great contributions to this thread. They have helped fill in some papers that I had not previously seen.

A4R

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #80 on: August 12, 2013, 12:09:28 AM »
This one looks as though it relates to methane in the context of rapid climate change episodes and methane clathrates (in a general context at least, I haven't read it closely enough yet to see exactly how well it might relate to the ESAS or Arctic in particular).

http://www.pnas.org/content/101/25/9187.full.pdf+html

On the whole, I think it seems premature and arguably foolish to discount methane (and especially clathrates) as a key driver of abrupt change in the earth system - especially if this paper is validly implicating them in the regular glacial cycle, which has occurred within recent paleoclimate. That would tend to refute the claims made in some quarters that there is no evidence for such occurrences in the past.

wili

  • Young ice
  • Posts: 3342
    • View Profile
  • Liked: 602
  • Likes Given: 409
Re: Melting Arctic an "economic time bomb"
« Reply #81 on: August 16, 2013, 02:17:46 AM »
One of the things that Archer and others base their claims (that relatively sudden release of methane is not possible in the Arctic) on is that there has (supposedly) been no mechanism put forward for how the methane could get into the atmosphere from deep under many meters of permafrost.

On the one hand, I think the authors that are concerned about rapid release have in fact presented a number of such mechanisms, and I can imagine a number of others that they haven't mentioned (that I've seen). On the other hand, I haven't seen much discussion from either side of the effects of what will likely be a much more robust and altered aquatic living community as the waters and sediments warm.

I wonder if there might arise an Arctic version of this critter, for example, eventually:

Quote
Off the coast of New Zealand, scientists have discovered a new methane seep habitat, where methane is being released. Andrew Thurber, a post doctoral fellow doing research at Oregon State University’s College of Earth, Ocean, and Atmospheric Sciences, is one of the primary researchers of the study. Thurber says methane seeps are found all over the world, but the one near New Zealand is different.

“It was dominated by this kind of worm called the ampharetidae,” Thurber said. “What was happening there was much more methane being released out of the sea floor than we expected, and much more than almost any other location on the planet.”

Thurber says the ampharetidae worm is releasing more methane from the ocean’s floor for two reasons.

“They live in tubes, which are burrows that go down into the sediment, and they create this type of chimney,” Thurber said.

The chimney-like tunnel allows the methane to seep out into the water columns
, Thurber says. But researchers say the worms aren’t just creating burrows. They are also eating bacteria that usually would consume much of the methane.

“Another thing we think they’re doing is they’re actually eating the bacteria and potentially the archaea – these two microorganisms that normally consume all the methane,” Thurber said, “So it’s essentially eating the filter that normally keeps the methane consumed and trapped within the sediment.”

http://www.kezi.com/worms-creating-methane-release-in-oceans/

"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

6roucho

  • Frazil ice
  • Posts: 296
  • Finance geek
    • View Profile
  • Liked: 0
  • Likes Given: 1
Re: Melting Arctic an "economic time bomb"
« Reply #82 on: August 17, 2013, 05:34:16 AM »
Why mustn't it be a headline in the media?
Because to convince people to change their society we need to keep a credible message.

One that is sober and based on the best science, not some wild speculation fed into an economic model to generate headlines for the authors.

The names lining up against this report are the names of well established credible voices for climate science.

Wild speculation fed into a glorified version of Sim City is not the most sober or defensible bit of science to be in the headlines.

This is true. Humans are drawn towards simplifying probabilities, and in the case of low probability events, no matter how severe the potential outcomes (indeed, especially if the potential outcomes are severe) this can lead to popular misunderstandings and thus distortions of the real mitigation actions that need to occur. Unfortunately there are already decision makers dismissing methane release as bad science, simply because alarmist reporting has made it an easy target, and this forms part of the general rhetoric against the idea of climate change.
« Last Edit: August 17, 2013, 06:21:05 AM by 6roucho »

wili

  • Young ice
  • Posts: 3342
    • View Profile
  • Liked: 602
  • Likes Given: 409
Re: Melting Arctic an "economic time bomb"
« Reply #83 on: August 17, 2013, 07:42:37 AM »
6r, good points, but I think the biggest tragedy is if we allow ourselves to be (self-) censored because of fear that some nitwit somewhere (who is sure to misrepresent the science and discussion, no matter what we say) may use our language as we struggle to understand all of the latest science to further muddy the topic.

They are going to muddy the topic whatever we say or don't say.

Let's just ignore them. OK?
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

6roucho

  • Frazil ice
  • Posts: 296
  • Finance geek
    • View Profile
  • Liked: 0
  • Likes Given: 1
Re: Melting Arctic an "economic time bomb"
« Reply #84 on: August 17, 2013, 01:03:32 PM »
wili, I share your anguish. The problem of the marketing of science is often an impediment to doing science. But we are where we are. Policymakers, with all their illogic, are crucial now. No bucks, no Buck Rogers.
« Last Edit: August 17, 2013, 01:16:34 PM by 6roucho »

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #85 on: August 17, 2013, 05:29:24 PM »
6r, good points, but I think the biggest tragedy is if we allow ourselves to be (self-) censored because of fear that some nitwit somewhere (who is sure to misrepresent the science and discussion, no matter what we say) may use our language as we struggle to understand all of the latest science to further muddy the topic.

The problem I see with methane is that otherwise well informed people rush to attack theories of catastrophic release potential with an almost religious fervour. This isn't a bunch of nutters running around saying judgement day is coming, that we'll all be killed by solar flares, or a magnetic field reversal or any one of the ridiculous doomsday scenarios you get if you ask a typical scientifically ignorant American prepper what they are preparing for.

There is some actual science here and at least some circumstantial evidence to suggest it's a real concern.

Furthermore a very real bottom line exists - by focusing so much effort on attacking the view that abrupt large scale methane release might be possible - people are implicitly (in many cases) denying (by not acknowledging) that methane is a serious problem and that we are very likely to at least see increased release. The reasonable parameters of debate largely revolve around "how much how fast" rather than "if". Any increasing source of methane at all at this stage is unhelpful (and not included in most models to my knowledge).

I have a feeling most of the abrupt thresholds would be aggressively denied as impossible by the same people in a similar way:
- rapid loss of Amazon forest
- rapid sea level rise
- rapid weather destabilisation
- rapid sea ice loss

etc.

Whether or not we understand how a process can happen or have cast iron evidence for it or not has no bearing on whether or not that process can and does happen.

ccgwebmaster

  • Nilas ice
  • Posts: 1085
  • Civilisation collapse - what are you doing?
    • View Profile
    • CCG Website
  • Liked: 2
  • Likes Given: 0
Re: Melting Arctic an "economic time bomb"
« Reply #86 on: August 24, 2013, 08:17:48 PM »
Interesting stuff about submarine landslides in relation to deglaciation - more details on one possible abrupt release mechanism for methane clathrates.

http://robertscribbler.wordpress.com/2013/08/23/the-methane-monster-grows-new-teeth-sea-level-rise-found-to-cause-slope-collapse-tsunamis-methane-release/

I recommend this blog in general actually, though I suspect many here already found it.

TerryM

  • First-year ice
  • Posts: 6002
    • View Profile
  • Liked: 893
  • Likes Given: 5
Re: Melting Arctic an "economic time bomb"
« Reply #87 on: August 24, 2013, 10:20:15 PM »
ccg
Thanks for the heads up. The article and the comments are thought provoking as i'd assumed that many (most?) of the slope failures were due to the sudden breakdowns of clathrates. The chicken or the egg i suppose.
Terry