Thawing Arctic Could Set Off Methane Climate Bomb

[latent aaaack]

This seems to have been missed by the media, although it's very new research that's still partly speculative. If the research was summarized accurately then the uncertainty seems to be whether it'll take years, decades, or centuries for the methane to be released, since the Arctic is already predicted to be free of summer ice in the near future.

Are current efforts to decrease emissions really mostly pointless last minute half-***ed long shots? It's time to plan more for the preparedness and survival aspect of it instead I say.



http://www.spiegel.de/international/world/0,1518,547976,00.html

It's always been a disturbing what-if scenario for climate researchers: Gas hydrates stored in the Arctic ocean floor -- hard clumps of ice and methane, conserved by freezing temperatures and high pressure -- could grow unstable and release massive amounts of methane into the atmosphere. Since methane is a potent greenhouse gas, more worrisome than carbon dioxide, the result would be a drastic acceleration of global warming. Until now this idea was mostly academic; scientists had warned that such a thing could happen. Now it seems more likely that it will.
...
The permafrost has grown porous, says Shakhova, and already the shelf sea has become "a source of methane passing into the atmosphere." The Russian scientists have estimated what might happen when this Siberian permafrost-seal thaws completely and all the stored gas escapes. They believe the methane content of the planet's atmosphere would increase twelvefold. "The result would be catastrophic global warming," say the scientists. The greenhouse-gas potential of methane is 20 times that of carbon dioxide, as measured by the effects of a single molecule.
...

Climate change could give an additional push to these trends. "If the Arctic Sea ice continues to recede and the shelf becomes ice-free for extended periods, then the water in these flat areas will get much warmer," said Overduin. That could lead to a situation in which the temperature of the sea sediment rises above freezing, which would thaw the permafrost."We don't have any data on that -- those are just suspicions," the Canadian scientist said.
...
"No one can say right now whether that will take years, decades or hundreds of years," she said. But one cannot rule out sudden methane emissions. They could happen at "any time."



edit - Hints of Methane's Renewed Rise (separate research done by NOAA)

http://news.bbc.co.uk/2/hi/science/nature/7364679.stm

Levels of the greenhouse gas methane in the atmosphere seem to be rising having remained stable for nearly 10 years.

Data from the National Oceanographic and Atmospheric Administration (Noaa) in the US suggest concentrations rose by about 0.5% between 2006 and 2007.

 

[INRM]

How much of a temperature rise will occur?

INRM

 

[latent aaaack]

I think the methane being released would mean either about a 6 C (10 F) or 12 C (20 F) increase assuming CO2 is kept to 550 ppm, the EU's target. Previously the IPCC predicted an increase of 3 C assuming 550 ppm of CO2. The IPCC's official predictions ranges from a 1.1 C increase to their worst case of a 6.4 C increase.

If my attempt at understanding this is correct then a 12 fold increase in methane content means adding what would be the climate impact equivalent of either (I don't know which because this article seems contradictory to me, see the botom of the post) 540 or 1848 ppm of CO2 to the existing concentration of CO2 which is 385 ppm. Adding that to a predicted future 550 ppm of CO2 that's a concentration of either 1090 ppm and 2398 ppm of CO2 in the atmosphere.

Either figure means all the ice melts which means a 75 meter increase in sea level over centuries and "at least a couple meters this century" if I understand this article correctly - http://www.guardian.co.uk/environment/2008/apr/07/climatechange.carbonemissions . I'm not using any other predictions from this researcher though except what a temp increase over 6 C means, I'm using the much more conservative IPCC numbers.

You can extrapolate what this means in terms of temp increase according to the IPCC:

http://environmentalresearchweb.org/cws/article/research/26986

This is the first time that the IPCC is providing such estimates. The report says that a greenhouse gas level of 650 ppm would be likely to warm the climate by around 3.6 °C; a level of 750 ppm would lead to a warming of 4.3 °C; 1000 ppm would lead to 5.5 °C; and 1200 ppm to 6.3 °C. To put this in context, the global atmospheric concentration of carbon dioxide in 2005 was 379 ppm while pre-industrial levels were roughly 280 ppm.

I don't know if an extrapolation would be valid from this data to 2400 ppm but if the 1848 ppm number is correct then that would be, even with a global concentration successfully kept down to 550 ppm, a rise of about 12 C.



Here's what I don't understand. There's 1.8 ppm of methane in the atmosphere and 385 ppm of CO2 and methane is 25 times more potent a greenhouse gas than CO2.

But:

From this article: http://www.sciencedaily.com/releases/2008/04/080423181652.htm

When related climate affects are taken into account, methane’s overall climate impact is nearly half that of carbon dioxide.

There are 385 ppm of CO2 in the atmosphere so if that quote means the impact of the current amount of methane is equal to nearly half of 385 then that's about 154 for 40% of 385. I think that means that a twelve fold increase in the current amount of methane would have the climate impact of 12 * 154 ppm of CO2 or 1848 ppm.

But then again if methane is only 25 times more potent than CO2 I would have thought that means 1.8 ppm has the same impact as 45 ppm of CO2 (1.8 * 25) which is 11.7% not 40%. 45 * 12 would be 540 ppm.

I have no idea which of these two versions is correct, if either.

 

[mhaze]

This seems to have been missed by the media, although it's very new research that's still partly speculative. If the research was summarized accurately then the uncertainty seems to be whether it'll take years, decades, or centuries for the methane to be released, since the Arctic is already predicted to be

free of summer ice in the near future.

http://www.spiegel.de/international/world/0,1518,547976,00.html

http://news.bbc.co.uk/2/hi/science/nature/7364679.stm

Propaganda once again from the infamous Richard Black of the BBC.

Coupled with propaganda from Hansen's 2008 paper, recently discussed here.

I'd ask a simple question before trying to read anything into the "rising methane levels". Methane was flat for ten years, then recently started a tiny possible rise.

Why was it flat?

Alternately, we could plough into -

• the distortions of fact in the popular articles linked to
• the scientifically unsupported conclusions in Hansen's 2008 paper
• the past history of biased reporting by Richard Black
• peer reviewed science that argues fairly conclusively against any problem with drunken trees, tundra and permafrost

Those are easy subjects to discuss.

But it isn't at all obvious why the global methane levels went flat for ten years.

If we can't conclusively point to why that happened, neither can we do very well at guessing why there is a slight rise now...

 

[thatguywhojuggles]

Hey, we could use all that methane to run electric generators.

 

[latent aaaack]

What does your question about why methane stayed flat for a while have to do with the possibility that melting permafrost could release massive amounts of methane? The problem isn't the small increase in atmospheric methane concentrations but melting areas of permafrost which have already been recorded to be releasing increasing amounts of methane into surrounding areas above the permafrost as the permafrost becomes more porous.

I only quoted Hansen on the ice caps melting if the temperature goes above 6 C which isn't central to the post so we can leave that alone.

Richard Black would not make a lie as outlandish as NOAA recording a methane rise. But that isn't central to the post either and I just included that link to show that other researchers have also recorded a methane rise and it may be because of melting permafrost.

• peer reviewed science that argues fairly conclusively against any problem with drunken trees, tundra and permafrost

What do you mean by this?

Propaganda once again from the infamous Richard Black of the BBC.

Coupled with propaganda from Hansen's 2008 paper, recently discussed here.

I'd ask a simple question before trying to read anything into the "rising methane levels". Methane was flat for ten years, then recently started a tiny possible rise.

Why was it flat?

Alternately, we could plough into -

• the distortions of fact in the popular articles linked to
• the scientifically unsupported conclusions in Hansen's 2008 paper
• the past history of biased reporting by Richard Black
• peer reviewed science that argues fairly conclusively against any problem with drunken trees, tundra and permafrost

Those are easy subjects to discuss.

But it isn't at all obvious why the global methane levels went flat for ten years.

If we can't conclusively point to why that happened, neither can we do very well at guessing why there is a slight rise now...

 

[mhaze]

Let's be realistic. Your cites alluded to recent rising methane levels possibly indicating the methane climate bomb was going off. I refuted that, just simply noting that we need to be able to say what caused methane to be flat for ten years, before setting a cause for a recent - very, very slight - rise. I've asserted that the cite from Black which leaned in this direct was pure propaganda.

Can the irrefutable hypothesis that the recent methane rise might possibly be attributed to the methane climate bomb going off be refuted? No, it is an irrefutable hypothesis. Suppose there had not been a tiny recent rise in methane. The same claim could be made, and it would be equally irrefutable. This is not science but is only Alarmist climate propaganda, when not put in the proper context.

The Arctic temperatures of the 1930s were similar to today, and there was no "methane climate bomb" - but that your sources seemed to not mention this inconvenient fact... Another, interesting question that I don't know the answer to is whether borehole temperature records exist for areas with supposedly thawing or thawable permafrost.

Research which may be of interest.

(summary and discussion at Worldclimatereport.com)

Delisle, G. 2007. Near-surface permafrost degradation: How severe during the 21st century? Geophysical Research Letters, 34, L09503, doi:10.1029/2007GL029323.

....The final sentence of the abstract states “Based on paleoclimatic data and in consequence of this study, it is suggested that scenarios calling for massive release of methane in the near future from degrading permafrost are questionable.” ...Delisle acknowledges that warming is occurring in the Arctic regions and that the warming will undoubtedly impact the permafrost of the high latitudes. The author notes, however, that many numerical models used to simulate the impact of warming on permafrost deal only with the upper 10 feet of the earth’s surface. The previously-used models do not take into account the cooling effect of deeper and colder zones that do interact thermodynamically with the active layer near the surface. Delisle also exposes other assumptions of previous models that are “in clear conflict with field evidence.”

...Delisle presents “a unidimensional long term permafrost temperature model of general application” “which is capable to fully incorporate all relevant thermal processes within the active layer and the permafrost, and between the permafrost and the non frozen ground below. The model space is made up of 600 layers with a minimum spacing of 10 cm within the active layer and the uppermost ‘‘permafrost zone.” Rather than look at only 10 feet into the surface as was done by previous models, the new model goes 100 yards into the surface, and is deemed as more realistic.

Well, with the improved model, Delisle reports that continuous permafrost in Alaska and Siberia will survive over the next 100 years, even if a significant warming takes place.

“Based on this result and on the presented analysis, it appears that all areas north of 60°N will maintain permafrost at least at depth. North of 70°N, surface temperature values today are in general below -11°C. These areas should maintain their active layer. It appears unlikely that almost all areas with near-surface permafrost today will lose their active layer within the next 100 years”....

“A second, rarely touched upon question is associated with the apparently limited amount of organic carbon that had been released from permafrost terrain in previous periods of climatic warming such as e.g. the Medieval Warm Period or during the Holocene Climatic Optimum. There appear to be no significant CH4-excursions in ice core records of Antarctica or Greenland during these time periods which otherwise might serve as evidence for a massive release of methane into the atmosphere from degrading permafrost terrains.”

 

[TsarBomba]

Novelist Jack Barnes wrote a scifi book about this concept (in his version started by an H-Bomb starting off a chain reaction releasing methane in the arctic seabed). Mother Of Storms.

 

[latent aaaack]

Mhaze - I'm not a scientist but as far as I can tell there is more research that points to a strong possibility of the methane being released vs. one paper that says it's much less likely. Furthermore that paper is 1 and a half years old while the research that seemingly contradicts that is recent. This new research measured methane levels that are 5 times greater than normal above the permafrost and the temperature is in fact getting very close to thawing temperature.

Data from offshore drilling in the region, studied by experts at the Alfred Wegener Institute for Polar and Marine Research (AWI), also suggest that the situation has grown critical. AWI's results show that permafrost in the flat shelf is perilously close to thawing. Three to 12 kilometers from the coast, the temperature of sea sediment was -1 to -1.5 degrees Celsius, just below freezing.

VS your linked to paper:

North of 70°N, surface temperature values today are in general below -11°C. These areas should maintain their active layer. It appears unlikely that almost all areas with near-surface permafrost today will lose their active layer within the next 100 years

So it seems that paper is out of date. Again, I'm not a scientist but -1.5 C is a big change from -11 C and, if I'm not mistaken, 1.5 C away from melting and releasing all the methane. If there's even 50/50 chance of that than that is indeed very "alarming" since that would mean a 20 F rise in temperature.