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  • 4 weeks later...
  • 3 weeks later...

I came across this too......http://www.nature.com/nature/journal/v490/n7421/full/nature11528.html?WT.ec_id=NATURE-20121025

Since hydrates can exist at higher temps as long as they are deeper, then trajectory changes in very warm currents such as the GS certainly might bring large temperature increases to sea floor regions in the Atlantic that contain such hydrates.

And the current changes in the Arctic might plausibly produce changes in the thermohaline dynamics of the GS capable of altering its course.

Sigh......

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  • 5 weeks later...

Hard for me to say if the budget cuts are intentionally aimed at climate measurements, since there are pretty widespread cuts going on in NOAA.

I will try to attend S&S's presentations as long as they don't conflict with something else closer to the "official" purpose of my going to the conference (e.g. my own presentation). I agree the context of their presentations and any audience discussion would be interesting.

Steve

Actually S&S presentations are in a poster session, so the "audience" will be those walking by the posters.

Meanwhile, the latest Arctic Methane Emergency Group press release is here: http://www.ameg.me/

AMEG PRESS RELEASE: 2012-11-21

Abrupt climate change is upon us. Farmers are angry. Food prices will go through the roof. The government’s climate change policy is in tatters. The government should have acted years ago. Now it may be too late.

The government is in the dog house, not for what they have done but what they have left undone. They have done much towards reducing CO2 emissions. The question is, will emissions reduction, however drastic, prevent abrupt climate change? The answer is ‘No’! The proof is that abrupt climate change is upon us.

There has been an elephant in the room, and it has been totally ignored.

It’s all about the Arctic sea ice.

It’s about the Arctic sea ice, whose reflection of sunshine keeps the planet cool. Remove the sea ice, and not only does the planet start to overheat, but the whole climate is suddenly changed. The global weather systems, on whose predictability farmers rely, are dependent for their stability on there being a temperature gradient between tropics and the poles. Remove the snow and ice at one pole, and the weather systems go awry and we have “global weirding”. Furthermore, the weather systems get stuck in one place, and we get weather extremes: long spells of hot/dry weather with drought, or long spells of cold/wet weather with floods.

This global weirding has started with a vengeance. The sea ice is rapidly disappearing. The behaviour of the polar jet stream is disrupted. Extreme weather events occur more often and with greater ferocity. And the food price index climbs and climbs.

There is an obvious relationship between strife and food – if you starve a nation they will fight to get food. This relationship has been pinned down by an organisation called the Complex Systems Institute, CSI. They show that the food riots break out when the food price index rises above a certain critical level. An example was the Arab Spring.

The current index is above the critical level. Because of extreme weather events this year, the index is expected to rise again in 2013. The UN’s food watchdog, the FAO, forecast that the index will rise even further in 2014.

Meanwhile the insurance industry is worried by the trend towards greater number and strength of extreme weather events, including hurricanes. Note that Sandy’s cost was greatly amplified by the diversion westward as it approached the coast off New York. Sandy had hit a jet stream blocking pattern. The loss of Arctic sea ice is leading to this kind of unusual event become more frequent. The insurers are worried, but governments should be even more worried, because extreme weather events will drive the food price index even higher.

So what can be done?

That is the subject of AMEG’s strategic plan, to be launched on Wednesday, 5th December, 6 pm, in San Francisco in association with the American Geosciences Union meeting there. Venue is to be announced.

For further information contact AMEG chair, John Nissen, [email protected], with subject line to include “AMEG launch”, phone +44 20 8742 3170 or skype john.nissen4.

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  • 2 weeks later...

http://www.nature.co...t-found-1.11988

Maybe an explanation for those ridiculously high SSTs near the mouth of the MacKenzie last summer?

I'd have to guess that the geologist was misquoted:

“We don't have proof in the geological record that any of that has ever happened before,” he said.

Hasn't the Storegga event been tied pretty tightly to clathrates & methane?

Terry

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I'd have to guess that the geologist was misquoted:

“We don't have proof in the geological record that any of that has ever happened before,” he said.

Hasn't the Storegga event been tied pretty tightly to clathrates & methane?

Terry

Not sure, although it certainly should have disrupted some methane clathrate beds.

The Storegga slide was followed by fairly rapid warming and sea level rise, featuring the flooding of Doggerland (i.e. most of what is now the North Sea) but I always thought that the proximate cause of warming of this period was due to the events that ended the Younger Dryas- i.e.the resumption of the North Atlantic thermohaline current. So the Storegga Slide may well have contributed to this warming, via methane release, but I don't know of any direct proof of it.

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Here are the three poster abstracts once again from S&S and their colleagues. Most fascinating to see the posters at the AGU meeting this past week and to talk with the authors.

B21D-0411: Methane carbon stable isotope signatures in waters and sediments of the Laptev Sea Shelf

Authors: Vladimir Samarkin1, Igor P Semiletov2, 3, Niko Finke1, Natalia E Shakhova2, 3, Samantha B Joye1

Session: B21D: Vulnerability of Permafrost Carbon to Climate Change III Posters

Section/Focus Group: Biogeosciences ( B)

C53A-0817: NEW EVIDENCE OF THE EXISTENCE OF GAS MIGRATION PATHWAYS THROUGH SUB-SEA PERMAFROST IN THE EAST SIBERIAN ARCTIC SHELF

Authors: Natalia E Shakhova1, 2, Igor P Semiletov1, 2, Alexander Salomatin2, Vladimir Yusupov2, Leopold Lobkovsky3, Nikolay Dmitrievsky3, Victor Karnaukh2, Denis Kosmach2, Denis Chernikh2, Roman Anan'ev3

Session: C53A: Climate Change and Cryospheric Systems III Posters

Section/Focus Group: Cryosphere ©

C53A-0818: DEGRADING SUB-SEA PERMAFROST AND SEDIMENTARY METHANE RELEASE IN THE SOUTHERN LAPTEV SEA, ARCTIC OCEAN

Authors: Igor P Semiletov1, 2, Natalia E Shakhova1, 2, Oleg Dudarev2, Vladimir Tumskoy3, Denis Kosmach2, Vladimir Samarkin4, Samantha B Joye4, Alexander Charkin2, Boris Bukhanov3, Eugene Chuvilin3, Nicolai Romanovskii3

Session: C53A: Climate Change and Cryospheric Systems III Posters

Section/Focus Group: Cryosphere ©

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Chris R has a nice piece at

http://dosbat.blogspot.co.uk/2012/12/something-wicked-this-way-comes.html

He discounts the possibility of a major methane release based as far as I can tell mainly on the fact that there wasn't one during the HTM and I'm not sure the HTM is comparable.since it was so much closer to the time that the ESAS was inundated.

I think he's a little optimistic but he provides plenty of sources and is definitely worth a read.

Terry

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I'd have to guess that the geologist was misquoted:

“We don't have proof in the geological record that any of that has ever happened before,” he said.

Hasn't the Storegga event been tied pretty tightly to clathrates & methane?

Terry

Maybe I am sticking my head in where it does not belong(yeah...probably) as I am NOT an expert on methane and this subject matter. So I am all ears here. My question is: weren't summers warmer in the Arctic during the Holocene Climatic Optimum 6-8 thousand YBP? This is what was in my climo course in 2008 so if it has been refuted over the past 4-5 years then fine. Please give me the reference. But if it still holds, is there evidence of excessive methane leaks in any kind of paleo data from this time period? That would be interesting because the climate did not warm much more and in fact cooled after this, as orbital parameters began to look more like what we have today. Also it was postulated during this time period that summer sea ice probably melted away and was seasonal. Polar bears still survived. The orbital variations (I believe precessional tilt) were favoring higher summer temperatures in the Arctic and NH 6-8K YBP. My point is that we may be looking at natural variations from a warming climate which are always exaggerated in the NH polar regions. That is a paleoclimatology fact. So any warming trend will be much higher in the NH polar regions and there is some breaking mechanism (unknown) that slow or negates the trend in methane releases. The earth has warmed rapidly in the past and the methane "death spiral" did not occur.

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Maybe I am sticking my head in where it does not belong(yeah...probably) as I am NOT an expert on methane and this subject matter. So I am all ears here. My question is: weren't summers warmer in the Arctic during the Holocene Climatic Optimum 6-8 thousand YBP? This is what was in my climo course in 2008 so if it has been refuted over the past 4-5 years then fine. Please give me the reference. But if it still holds, is there evidence of excessive methane leaks in any kind of paleo data from this time period? That would be interesting because the climate did not warm much more and in fact cooled after this, as orbital parameters began to look more like what we have today. Also it was postulated during this time period that summer sea ice probably melted away and was seasonal. Polar bears still survived. The orbital variations (I believe precessional tilt) were favoring higher summer temperatures in the Arctic and NH 6-8K YBP. My point is that we may be looking at natural variations from a warming climate which are always exaggerated in the NH polar regions. That is a paleoclimatology fact. So any warming trend will be much higher in the NH polar regions and there is some breaking mechanism (unknown) that slow or negates the trend in methane releases. The earth has warmed rapidly in the past and the methane "death spiral" did not occur.

6-8k years ago the oceans were still rising, and had been for 5k years(at a much faster rate). This gives little time for shallow hydrate formation, and the rising ocean stabilizes the deeper hydrates.

holocene-sea-level-rise-graph.jpg?w=450&h=319

edit: That is to say the top of the hydrate stability zone(where it is relatively easy to destabilize), would have hardly any hydrates to destabilize.

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6-8k years ago the oceans were still rising, and had been for 5k years(at a much faster rate). This gives little time for shallow hydrate formation, and the rising ocean stabilizes the deeper hydrates.

holocene-sea-level-rise-graph.jpg?w=450&h=319

edit: That is to say the top of the hydrate stability zone(where it is relatively easy to destabilize), would have hardly any hydrates to destabilize.

Blizzard should keep in mind, too that CO2 levels during the HTM never rose above about 280 ppm. As we approach 400 ppm (on our way to 500 ppm or greater) we are pushing the climate into conditions not seen for millions of years.

ice_core_co2.png

[source]

If one understands the GHE and the properties of CO2 and other GHGs it is hard to hope that some unknown 'braking effect' will appear and save us from the consequences of BAU.

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6-8k years ago the oceans were still rising, and had been for 5k years(at a much faster rate). This gives little time for shallow hydrate formation, and the rising ocean stabilizes the deeper hydrates.

holocene-sea-level-rise-graph.jpg?w=450&h=319

edit: That is to say the top of the hydrate stability zone(where it is relatively easy to destabilize), would have hardly any hydrates to destabilize.

Blizzard should keep in mind, too that CO2 levels during the HTM never rose above about 280 ppm. As we approach 400 ppm (on our way to 500 ppm or greater) we are pushing the climate into conditions not seen for millions of years.

ice_core_co2.png

[source]

If one understands the GHE and the properties of CO2 and other GHGs it is hard to hope that some unknown 'braking effect' will appear and save us from the consequences of BAU.

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post-6603-0-71206000-1355422080_thumb.pn

This is the Arctic ocean temperature at hydrate depth two years ago.

post-6603-0-07972600-1355422091_thumb.pn

Here is the same depth today(the scale is the same the data for today is kelvin two years ago, centigrade).

hydrates_a_graph1.jpg

In the arctic the hydrates should start just below the 300 meter level due to the 1-2C temperatures.post-6603-0-05958400-1355423028_thumb.pn

post-6603-0-50993500-1355423044_thumb.pn

The heat influx is getting down to the 400 meter level, where there are definitely hydrates.

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post-6603-0-71206000-1355422080_thumb.pn

This is the Arctic ocean temperature at hydrate depth two years ago.

post-6603-0-07972600-1355422091_thumb.pn

Here is the same depth today(the scale is the same the data for today is kelvin two years ago, centigrade).

hydrates_a_graph1.jpg

In the arctic the hydrates should start just below the 300 meter level due to the 1-2C temperatures.post-6603-0-05958400-1355423028_thumb.pn

post-6603-0-50993500-1355423044_thumb.pn

The heat influx is getting down to the 400 meter level, where there are definitely hydrates.

That's very interesting. So are global methane levels expected to rise dramatically soon? I saw a talk on climate change recently by Dr. Dressler and he stated that methane levels have risen sharply over the past 100 years or so but have stabilized (for now) and we don't quite understand all the processes that govern its atmospheric concentrations. He did not focus on this much. It was more of a sidebar in his talk.

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post-6603-0-71206000-1355422080_thumb.pn

This is the Arctic ocean temperature at hydrate depth two years ago.

post-6603-0-07972600-1355422091_thumb.pn

Here is the same depth today(the scale is the same the data for today is kelvin two years ago, centigrade).

hydrates_a_graph1.jpg

In the arctic the hydrates should start just below the 300 meter level due to the 1-2C temperatures.post-6603-0-05958400-1355423028_thumb.pn

post-6603-0-50993500-1355423044_thumb.pn

The heat influx is getting down to the 400 meter level, where there are definitely hydrates.

Fortunately the area of the ocean that shows warming is 3000m deep so there are another 2700m to go.

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The HTM also occurred relatively shortly after the ESAS was inundated. According to S&S the thermal pulse from that shock warming has been traveling downward ever since. I assume that the Mackenzie Delta Region and other shallow Arctic basins suffer the same conditions.

We're talking about two separate heat pulses, the one that occurred as water levels rose & the modern one, both squeezing the permafrost & hydrate cap from above against the geo-heating from below. Add in a Storegga event or two to stir things up (check the Pingo features) & we've got real problems.

We haven't reached HTM conditions yet, at least in Greenland, but could in very short order. When Flade Isblink melts out (It was -10 yesterday ~20C above normal), all bets are off.

Skier

Not following the 3 km comment- we're in very shallow waters.

Terry

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Fortunately the area of the ocean that shows warming is 3000m deep so there are another 2700m to go.

The warmed area is between 400m to 0m depth so I don't know what you are talking about.

post-6603-0-09376800-1355432476_thumb.pn

post-6603-0-20751700-1355433666_thumb.pn

New scale -2C - +2C

This is the new mechanism for ice loss convection of warm water from depth. Here is thickness a year ago:

post-6603-0-26640400-1355433410_thumb.pn

post-6603-0-36136200-1355433473_thumb.pn

This convection is torching a huge area and thinned it by 0.5m - 2m or more at N.E. Greenland. Its quit alarming 0.47m at 88.7N. It has lost at least 500 km3 on the Atlantic side through a combination of melting and failure to thicken.

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That's very interesting. So are global methane levels expected to rise dramatically soon? I saw a talk on climate change recently by Dr. Dressler and he stated that methane levels have risen sharply over the past 100 years or so but have stabilized (for now) and we don't quite understand all the processes that govern its atmospheric concentrations. He did not focus on this much. It was more of a sidebar in his talk.

I don't know if anyone else has factored in this huge influx of heat into the arctic basin. I have not read anything about it anywhere. I found it only because I was expecting it. In the past these depths did nothing year round, so I guess no one else bothers to look.

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The warmed area is between 400m to 0m depth so I don't know what you are talking about.

Your point was that warming was going to cause methane release. The area of warming you showed was at 300m and 400m but the depth of the ocean in that same area is 3000m. That means that the warming is 2600-2700m from the bottom of the ocean. How can warming 2700m above the ocean floor causing methane release on the ocean floor?

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Your point was that warming was going to cause methane release. The area of warming you showed was at 300m and 400m but the depth of the ocean in that same area is 3000m. That means that the warming is 2600-2700m from the bottom of the ocean. How can warming 2700m above the ocean floor causing methane release on the ocean floor?

http://scitechdaily....ound-in-arctic/

http://marine.usgs.g...ates/title.html

There are significant methane hydrates in the 300-400m depths of the arctic, on the slopes of the continental shelves.

edit;

Every time I post you make up numbers and contradict me.

Just how long did it take me to find references for the depths of the hydrates? About 30 seconds. Try using google and google scholar. Stop making up numbers to suit your purpose.

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http://scitechdaily....ound-in-arctic/

http://marine.usgs.g...ates/title.html

There are significant methane hydrates in the 300-400m depths of the arctic, on the slopes of the continental shelves.

Every time I post you make up numbers and contradict me.

You posted images of warming at 300m-400m when in reality your warming area is some of the deepest areas in the arctic that is his point.

IBCAO_betamap.jpg

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You posted images of warming at 300m-400m when in reality your warming area is some of the deepest areas in the arctic that is his point.

IBCAO_betamap.jpg

post-6603-0-56997800-1355443475_thumb.pn

post-6603-0-51249400-1355443520_thumb.pn

It accumulates in the middle, then it spreads out. It has made significant advances in just 3 months. When will it get there? This winter, maybe. Next year when it gets another gush of Gulf Stream water, probably. But at this rate of advance we are not talking decades.

edit;

Significantly warmed 2-3C water has already reaches the continental shelves of Greenland, Siberia, the CA, and there is a patch on the Scandinavian CS. While the worst of it is still a ways off, the warming has already begun.

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