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Small percentage? Large portion?

Who cares?

What is the likelihood of of an extra 50Gt being released suddenly or more slowly over time?

How about 1,400Gt?

50Gt over 100 years would be plenty bad enough, generating a climate forcing the equal to a doubling of CO2 and effectively doubling warming due to human activities alone.

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I've caught a case of the giggles after reading through this thread.

If in the unlikely case that warming resumes, the effect of CH4 emissions that may or may not result will be undetectable. I can provide powerful evidence of this.

The previous interglacial period was much warmer than today, perhaps by 3-4C, and the temperature still plummeted 8-10C into the next ice age within centuries, while no global warming resulted from CH4 release, In reality we cooled dramatically while GHGes were at their highest. The Holocene climate optimum also featured warmer temperatures than those of today, and no explosive greenhouse warming resulted.

http://www.climate4you.com/images/VostokTemp0-420000%20BP.gif

Climate change in+around Greenland.

http://www.climate4you.com/images/GISP2%20TemperatureSince10700%20BP%20with%20CO2%20from%20EPICA%20DomeC.gif

As for the interglacial cycles, and periods of rapid internal variability such as the younger dryas, the causative mechanisms do not involve surface albedo or greenhouse gases.

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Please stop posting easily refutable skepticalscience blog fluff. None of the temperature data referenced were recorded on the Greenland ice sheet nor within the resolution window, which automatically invalidates it. The distinction is important by the means of albedo.

Also please be aware of when applying instrumental measurements is acceptable and when it is not. GISP contains a 30yr resolution, so instrumental data must be averaged to this resolution window as well.

SkepticalScience as a reference shows poor scientific etiquette.

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I quoted real science from a reputable site, which shows that the images you posted were doctored.

I have no idea why the mods have not rebanned BethesdaBoy.

For the umpteenth time I have no idea who or what you are talking about. But if you were to actually read the paper you linked, perhaps the issue would become clearer. The skepticalscience blog images are doctored because they contain an inadequate resolution window and do not reflect conditions on the icepack itself.

The readings were not measured on the ice cap, and contradict satellite data over the GISP2 region. This is directly a consequence of albedo fluctuation.

For the record, DO18 is not a polar temperature proxy, It is more of a mid latitude SST proxy.

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For the umpteenth time I have no idea who or what you are talking about. But if you were to actually read the paper you linked, perhaps the issue would become clearer. The skepticalscience blog images are doctored because they contain an inadequate resolution window and do not reflect conditions on the icepack itself.

The readings were not measured on the ice cap, and contradict satellite data over the GISP2 region. This is directly a consequence of albedo fluctuation.

For the record, DO18 is not a polar temperature proxy, It is more of a mid latitude SST proxy.

If I recall correctly all graphs and data from Skeptical Science are sourced - if you think there is a problem with any of them, it's possible to contact the agency that published them originally. Referring to them as "doctored" shows total contempt for the English language.

Terry

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If I recall correctly all graphs and data from Skeptical Science are sourced - if you think there is a problem with any of them, it's possible to contact the agency that published them originally. Referring to them as "doctored" shows total contempt for the English language.

Terry

The images were created by skepticalscience blog. I don't have any problem with citing peer reviewed proxy evidence but correctly measuring and applying comparative datasets is very important to me. Thanks.

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the images you posted are based on faulty science

more here (which you won't read but maybe a mod will finally read and curtail your posting of faked graphs and debunked nonsense): http://www.skepticalscience.com/news.php?

n=57

I've explained to you why the data presented on skepticalscience blog is nonsense. For the sake of scientific etiquette you'd heed my advice and stop citing that blog.

1. The GISP DO18 isotope cores present a 30yr resolution window, instrumental data must be fitted in this window of scew resolution. Skepticalscience blog creates a graph that does not abide by this reality.

2. The measurements skepticalscience blog cites were not taken on the Greenland icecap elevated many 1000s of feet. That alone invalidates skepticalscience blog.

3. DO18 is more representative of tropical or mid latitude SSTs than it is polar temperature. Skepticalscience blog has a well known lack of physical understanding, evidenced by their widely discredited TSI - Smoothed surface temp comparison which treats the oceans as having instantaneous thermal capacity and response time.

Next time you might want to think of a better source, John Cook (skepticalscience blog runner) is entrenched in political activism.

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I hear you Rusty... I just keep going back to the thread title that not many seem to object to.

catastrophic climatic calamity? really?

Just a bit of alliterative humor. Though it is something that is possible, given the unique combination of warming temperatures with sediments on a shallow shelf becoming unstable...

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Here are links to two research papers I came across in learning more about the physical processes involved with undersea methane release. The first is an older article: Giant sea-bed pockmarks: evidence of gas escape from Belfast Bay, Maine - Kelley et al 1994 link Here is the abstract from that paper:

Circular depressions, or pockmarks, cover the sea floor in many estuarine regions of the western Gulf of Maine. In Belfast Bay, Maine, they are found in densities up to 16/km
2
, are up to 350 m in diameter and 35 m in relief, and are among the largest and deepest known. The pockmarks appear to form from the escape of biogenic natural gas and pore water and are far larger than features associated with thermogenic gas elsewhere. These pockmarks are thought to have formed (1) catastrophically during earthquake, tsunami, or storm, or (2) slowly over thousands of years. Recent observations of bubble releases suggest continuing activity and potential geologic hazard. The pockmarks involve a poorly documented coastal process of sediment redistribution and methane release, largely unrecognized an the rock record but widespread in middle- to high-latitude embayments.

The paper is an easy read and has some great sonar images of these gas escape features.

The second paper is paywalled, so only the abstract is available for all, but it more directly deals with methane release and climate change.

Atmospheric methane from organic carbon mobilization in sedimentary basins — The sleeping giant? Kroeger et al 2011 link And its abstract:

The mass of organic carbon in sedimentary basins amounts to a staggering 10
16
t, dwarfing the mass contained in coal, oil, gas and all living systems by ten thousand-fold. The evolution of this giant mass during subsidence and uplift, via chemical, physical and biological processes, not only controls fossil energy resource occurrence worldwide, but also has the capacity for driving global climate: only a tiny change in the degree of leakage, particularly if focused through the hydrate cycle, can result in globally significant greenhouse gas emissions.

To date, neither climate models nor atmospheric CO
2
budget estimates have quantitatively included methane from thermal or microbial cracking of sedimentary organic matter deep in sedimentary basins. Recent estimates of average low latitude Eocene surface temperatures beyond 30 °C require extreme levels of atmospheric CO
2
. Methane degassing from sedimentary basins may be a mechanism to explain increases of atmospheric CO
2
to values as much as 20 times higher than pre-industrial values. Increased natural gas emission could have been set in motion either by global tectonic processes such as pulses of activity in the global alpine fold belt, leading to increased basin subsidence and maturation rates in the prolific Jurassic and Cretaceous organic-rich sediments, or by increased magmatic activity such as observed in the northern Atlantic around the Paleocene–Eocene boundary. Increased natural gas emission would have led to global warming that was accentuated by long lasting positive feedback effects through temperature transfer from the surface into sedimentary basins. Massive gas hydrate dissociation may have been an additional positive feedback factor during hyperthermals superimposed on long term warming, such as the Paleocene–Eocene Thermal Maximum (PETM). As geologic sources may have contributed over one third of global atmospheric methane in pre-industrial time, variability in methane flux from sedimentary basins may have driven global climate not only at time scales of millions of years, but also over geologically short periods of time. Earth system models linking atmospheric, ocean and earth surface processes at different timescales with the sedimentary organic carbon cycle are the tools that need to be developed in order to investigate the role of methane from sedimentary basins in earth's climate.

I'm too cheap to pay for the article but if anybody has it I'd love to read the whole thing.

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Just a bit of alliterative humor. Though it is something that is possible, given the unique combination of warming temperatures with sediments on a shallow shelf becoming unstable...

According to some other posters in this thread, nothing about this is funny. When do you think a catastrophic climatic calamity could commence wrt CH4?

The language used is for dramatic effect and exposes the OP for the alarmist he is. It's fine with me, I don't buy into the CH4 alarmism, the thread title discredits the concern to many folks and it's chalked up to alarmism. So I hope the title stays I just like pointing out how absurd it is and how statements like that hurt the cause of people concerned about CH4.

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According to some other posters in this thread, nothing about this is funny. When do you think a catastrophic climatic calamity could commence wrt CH4?

The language used is for dramatic effect and exposes the OP for the alarmist he is. It's fine with me, I don't buy into the CH4 alarmism, the thread title discredits the concern to many folks and it's chalked up to alarmism. So I hope the title stays I just like pointing out how absurd it is and how statements like that hurt the cause of people concerned about CH4.

we consider release of up to 50 Gt of predicted amount of hydrate storage as highly

possible for abrupt release at any time. That may cause 12-times increase of modern

atmospheric methane burden with consequent catastrophic greenhouse warming.

http://www.cosis.net/abstracts/EGU2008/01526/EGU2008-A-01526.pdf

This is from the article you cited. Why do you keep asking questions you have already answered?

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The question was for the met I responded to. I wanted to know when he felt like it could occur.

Hard to say exactly, though I haven't seen much in the way of rebuttal of what S&S are warning about. At a minimum we need much more thorough monitoring of this region to look for corroboration of any acceleration in release or related changes.

Looking to the past, it's true this probably hasn't happened in the previous ice ages over the past 400000 years or so, though it's unclear whether these periods had the same setup and shallowness of the ESAS. Over Earth's history in general, this type of thing may well have happened, given the past greatly elevated levels of CO2.

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They say the Beaufort Sea, in the western Canadian Arctic, holds clues to several environmental mysteries of global significance - chief among them why so much methane, a potent greenhouse gas, is now seeping out of the sea floor.

EVIDENCE OF LEAKING METHANE

More worrisome to many observers is the massive store of methane sitting beneath the permafrost in the form of gas hydrates.

The gas has been trapped under the sea for thousands of years, but there is mounting concern - and evidence - that it is leaking out as the climate warms.

In the past few years, dramatic plumes of the methane have been spotted by teams surveying waters off Siberia. A Canada-U.S. team has also found "extensive free gas release" on the Beaufort Shelf, which is pock-marked with holes the escaping gas leaves behind.

At one spot about 50 metres below the surface, the team's remotely operated vehicle found gas "vigorously and continuously" bubbling out of a sea mound, kicking up clouds of sediments.

The chemical signature of the gas seeping out from the Beaufort Sea floor indicates much of it is bubbling up through cracks and gaps in the permafrost that are liberating methane that has been locked under the sea for at least 50,000 years, Dallimore and his colleagues report.

How much methane is entering the atmosphere, and whether the rate is increasing as Arctic ice retreats and the climate warms, is not known. But scientists say it is important to find out because methane is 20 times more potent as a greenhouse gas than car-bon dioxide.

The permafrost and vast hydrate deposits in the shallow waters of the Arctic pose "a potentially significant geohazard and may release vast amounts of methane to the atmosphere," geologist Matt O'Regan, at Cardiff University in Britain, says in a report outlining the "urgent need" for the scientific drilling.

Read more: http://www.vancouversun.com/technology/Scientists+eager+drill+Arctic+waters+answers+about+methane/6535248/story.html#ixzz1tOLxmL7T

So it is now leaking out of the Beaufort side as well.

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So it is now leaking out of the Beaufort side as well.

This almost doubles the area of continental shelf with destabilized hydrates. Would this double the S&S warning of a possible 50GT release to a possible 100GT release? Wasn't that the worst case scenario that was discussed? The issue is not the amount, but rather the time frame. The rate of release. If it takes place over a couple hundred years, it would only amount to a watt or so of climate forcing. But if there were a decade time frame it would be 5-10W/m^2. The albedo feedback would add many more watts to that in the northern hemisphere.

The risk we area taking in inaction is enormous.

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  • 2 weeks later...

http://www.annualreviews.org/doi/full/10.1146/annurev-earth-042711-105329

New paper out concluding that the high rate of CO2 release combined with the resulting ocean acidification that we are seeing today is best comparable with the Permian mass extinction - the largest of them all.

The role of acidification and deep ocean anoxia is important, because it suggests that the base of the food chain - ocean invertebrates - may be threatened much more now than during more recent high CO2 episodes (e.g. the PETM), which came on more gradually.

This isn't only about CH4, but its implications are certainly not good - hence the post in this thread.

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The central arctic farted.

I'd like to know how the Greenland Ice cap farts - at least the southern part. Isn't it too soon to see any kind of melt there? Or is it now supporting CH4-producing bacteria that can be metabolically active below freezing and beneath this last winter's snowpack.

Inquiring minds, you know......

Also, those images would impress me more if they extended the scale beyond 1870ppm

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I'd like to know how the Greenland Ice cap farts - at least the southern part. Isn't it too soon to see any kind of melt there? Or is it now supporting CH4-producing bacteria that can be metabolically active below freezing and beneath this last winter's snowpack.

Inquiring minds, you know......

Also, those images would impress me more if they extended the scale beyond 1870ppm

Good catch - I'd missed that entirely.

Terry

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I'd like to know how the Greenland Ice cap farts - at least the southern part. Isn't it too soon to see any kind of melt there? Or is it now supporting CH4-producing bacteria that can be metabolically active below freezing and beneath this last winter's snowpack.

Inquiring minds, you know......

Also, those images would impress me more if they extended the scale beyond 1870ppm

I agree that the scale needs extending, particularly since the typical arctic CH4 readings are currently around 1900 ppm, and transient readings have gone as high as 2500 ppm this year. Here is the Barrow Obervatory in-situ hourly averagereadings for 2012:

ccgg.BRW.ch4.4.none.hourly.2012.2012.png

It will be interesting to see if the summer melt season brings more evidence of undersea CH4 releases.

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  • 2 weeks later...

http://www.scientificamerican.com/article.cfm?id=more-than-150000-methane-seeps-appear-as-arctic-ice-retreats

Scientists have found more than 150,000 sites in the Arctic where methane is seeping into the atmosphere, according to a report published Sunday in the journal Nature Geoscience.

Aerial and ground surveys in Alaska and Greenland revealed that many of the methane seeps are located in areas where glaciers are receding or permafrost is thawing as the climate warms, removing ice that has trapped the potent greenhouse gas in the ground.

Researchers at the University of Alaska and Florida State University say the amount of methane being released from the seeps now is relatively small but could grow in coming decades as climate change intensifies, shrinking the ice that has prevented ancient deposits of the heat-trapping gas from reaching the atmosphere.

"As permafrost thaws and glaciers retreat, it is going to let something out that has had a lid on it," said lead author Katey Walter Anthony of the University of Alaska.

Scientists have long known of the existence of methane seeps in the Arctic, but the new study is one of the first to map them over large areas.

Walter Anthony and her colleagues used airplanes to fly over 6,700 lakes in Alaska during the winters of 2008, 2009 and 2010.

The survey revealed 77 previously unknown seep sites, which the scientists narrowed down to 50 lakes they visited on foot.

They documented the seeps they found, using carbon-dating to determine the age of methane released at the sites. The scientists performed the same analysis at 25 lakes in western Greenland.

Seep sites in Alaska tended to occur where permafrost is thawing or at the edges of receding glaciers. In Greenland, the scientists found seeps in places where glaciers have retreated over the past 150 years, since the end of the Little Ice Age.

The researchers calculate that methane seeps in Alaska alone are releasing 250,000 metric tons of methane into the atmosphere each year, 50 to 70 percent more than previously estimated.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

Going up.

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Geologic methane seeps along boundaries of Arctic permafrost thaw and melting glaciers

http://www.nature.co...l/ngeo1480.html

"These seeps were characterized by anomalously high methane fluxes, and in Alaska by ancient radiocarbon ages and stable isotope values that matched those of coal bed and thermogenic methane accumulations."

This seems to be the money quote.

The release of LIA era CH4 from the Greenland sites may not be of great consequence, since Greenland has not exactly been a compost heap for the past 500 years.

However, they seem to have direct evidence that ancient CH4 is being released from melting permafrost in Alaska. Since there could be a very great deal of methanogenic C in/under that permafrost - and since the CH4 from those deposits may have been generating it and then trapping it for thousands of years, there would seem to be some cause for concern......

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  • 3 weeks later...

An interesting graph by Yurganov

ftp://asl.umbc.edu/pub/yurganov/methane/AIRS_CH4%20_2002-2012.pdf

I'm not convinced that much of the 'blue ice' we're seeing isn't the result of methane being gobbled by beasties beneath the ice. This winter we should have plenty of time to review the MODIS images to see if blue ice isn't most prominent in known methane rich locals.

Terry

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An interesting graph by Yurganov

ftp://asl.umbc.edu/pub/yurganov/methane/AIRS_CH4%20_2002-2012.pdf

I'm not convinced that much of the 'blue ice' we're seeing isn't the result of methane being gobbled by beasties beneath the ice. This winter we should have plenty of time to review the MODIS images to see if blue ice isn't most prominent in known methane rich locals.

Terry

The "blue ice" phenomenon is interesting - at first I though it was regional (limited to fast ice and kettle lakes in the Lena Delta region), then it became clear that much of the CAA has it as well. Lots of Greenland glaciers too.

But look at the uploaded file of the Ob'/Taz estuaries as they melted recently (fair weather, 5/28 to 6/9).

The ice starts as gray - turns white before melting and assumes a bluish cast only just before the final melt (last frame - Ob' only)

So the blue ice does after all have an important regional component, which would favor the involvement of CH4 release (or the blooming of CH4 eating microbiota).

I'd have thought the lower Ob' would have LOTS of CH4, though.

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Chaunskaya Gulf, next to Pevek has gone from blue back to white over the last week. My understanding is that many of the biota have very short life cycles and can imagine a case in which methanophiles gobble the available methane (ice still white), are eaten by phytoplankton getting by on solar radition through the ice (blue ice), which after a relatively short period die off (white ice)and are not able to regrow another bloom due to the absence of methanophiles which can't handle the now oxygenated environment.

If sufficient methane is present the cycle keeps repeating (blue ice), but if a toxin is introduced or if the under ice surface becomes too oxygenated to support the methanophiles, the ice returns to its white state.

Or it could be that a little snow has fallen.

Terry

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