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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #50 on: July 11, 2013, 08:42:17 PM »
As a side note to my immediately preceeding post, Omar notes in his first video that methane emissions are currently being observed in desert areas, particularly after rainfall events.  While I am no expert on this topic; I observe that the increase in atmospheric carbon dioxide has lead to the recent observations of increased vegetation growth in deserts; and it may be possible that rainfall events in the deserts temporarily lead to a breakdown of the increase organic matter into methane, and once the rain has passed the breakdown of the organic matter would return to emitting carbon dioxide.
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Re: Antarctic Methane Concentrations
« Reply #51 on: July 11, 2013, 11:03:55 PM »
I would also like to note that Omar states in his video that the winds are blowing the wrong way to accummulate methane in the upper Antarctic atmosphere (troposphere).  However, while I am not an expert, the attached image of the origins of Katabatic winds and how they blow outward from the surface of the Antarctic; implies to me that atmosphere from the Antarctic perimeter must be drawing into the upper Antarctic troposphere as indicated by the arrows in the attached figure.  In my opinion this provides an explanation of how the marine emissions of methane from hydrate decomposition could migrate over Antarctica where it could accumulate in the Austral Fall and early Winter.
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Re: Antarctic Methane Concentrations
« Reply #52 on: July 12, 2013, 04:33:26 PM »
Not to be too assiduous on this topic but I thought that I would post the following additional arguements/evidence in favor of the marine hydrate source of Antarctic atmospheric methane as opposed to Albert Kallio's theory:

First, the following 2010 internet article cites a couple of examples of methane hydrate leakages from the Antarctic seafloor associated with local warming of the coastal waters of the Southern Ocean (this supports the seasonality of my theory):

"Argentine Geologist Finds Gas Venting Into Antarctic Ocean From Seafloor To Be 99% Methane - Nature:
Persistent bubbling is stirring the water's surface in the Erebus and Terror Gulf, a remote spot off the Antarctic Peninsula. When he saw the commotion in 2000, Argentinian geologist Rodolfo del Valle was intrigued — despite 38 years' experience in the region. There was a chance the gas contained methane, and when del Valle's team investigated the leak they discovered it to be 99% methane.

This is bad news. The gas is not only 25 times more powerful than carbon dioxide at heating the atmosphere; methane hydrates locked up in the Antarctic seabed and ice also contain vast amounts of carbon — overall, methane deposits contain about half of global carbon. With a recorded decline in Antarctic ice shelves, the long-term effect of deteriorating and melting ice could range from boosting global warming to helping trigger mass extinctions. Nature caught up with del Valle on the eve of his departure for the first on-the-ground study to quantify methane leakage in shallow waters and ice in the Gulf.


Q: Will you be investigating any direct consequences of methane leakage around the northern Antarctic peninsula?

A: The British Falkland Islands Dependencies Aerial Survey Expedition findings from the mid-1950s showed unusual numbers of crabeater seals dying in this area. Members of the expedition suggested that methane could be implicated. During the calving season, seals live and give birth on top of the frozen layer of sea, and dive for food through holes in the ice. One theory is that methane accumulates under the marine ice and escapes through cracks during low tides. The methane deposits located below the ice then expand. These emissions would be responsible for the massive death of seals: methane is usually accompanied by hydrogen sulphide, a toxic metabolite of methanogenic bacteria at the seabed. So we'll be looking at that in connection with the seal deaths."


Second, while the NOAA methane South Pole flask measurement are only reported to the end of January 2013 at the following website, I believe that when the rest of 2013 flask data is reported by NOAA that no unusual releases will be reported at the ground based readings; which would support my idea that the methane floats up over the ocean and is moved by upper tropospheric winds over the continent, thus bypassing the NOAA ground based flask readings:

http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts]http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts


Third, as the continental crust is unusually thin in the West Antarctic and unusually thick in the East Antarctic if Albert Kallio's theory were true then would would expect to see higher atmospheric methane readings over the West Antarctic as compare to the East Antarctic, but this is the opposite of what is observed.  While by my theory the atmospheric heat telecommunicated from the Pacific Tropics to the West Antarctic atmosphere would make this air too warm to slow the OH oxidation of CH4; while the East Antarctic atmosphere temperature would be just right to match my assumptions.
« Last Edit: July 12, 2013, 08:43:46 PM by AbruptSLR »
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Apocalypse4Real

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Re: Antarctic Methane Concentrations
« Reply #53 on: July 12, 2013, 08:07:20 PM »
Abrupt SLR,

I'll comment more later, but what might help all of us is if you can find sources that map the wind patterns in the Antarctic from the time that high concentration began to current date, to help us understand the high concentrations of Antarctic methane this winter.

I have not read the above thread, if you answered the question already, my apologies.

I hope you'll continue to explore methanetracker.org as it continues to help us build a picture of global methane concentration.

A4R

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Re: Antarctic Methane Concentrations
« Reply #54 on: July 12, 2013, 10:15:32 PM »
A4R,

I imagine that the resolution of identifying the source of the Antarctic methane will take some time, and combining the historical winds with the measured methane concentrations would be a major step forward on this matter.  Part of the problem with the wind is that it is different at different altitudes/elevations, and I am not sure that we can find the type of historical wind data that you need, but if you have the time, you might want to look through the data available at the following sites:

http://www.weather-forecast.com/maps/Antarctica

http://ossfoundation.us/projects/environment/global-warming/projects/environment/global-warming/current-climate-conditions/storm-trends#section-2

https://amrc.ssec.wisc.edu/

http://pansy.eps.s.u-tokyo.ac.jp/ResearchTopics-e.html


Regarding possible ocean sources for methane, it is possible that they are distributed all around much of the Antarctic coastline, as the attached image from Rignot et al 2013 implies that at least seasonally the coastal ocean water is at least warm enough to cause basal ice melting of the ice shelves all around Antarctica; which by extension implies that that ocean water was at least seasonally warm enough to decompose any methane hydrates near the seafloor.
« Last Edit: July 12, 2013, 11:01:57 PM by AbruptSLR »
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #55 on: July 13, 2013, 04:42:13 PM »
A4R,

A few more points that you should consider when evaluating how reasonable any theory (eg Albert Kallio's) is that proposes that methane leaks through thousands of meters of East Antarctic Ice Sheet directly into the atmosphere above, include:

- Kallio assumes that the heat decomposing the methane hydrate comes from below the crust; which would imply that at least many hundreds of meters of hydrate containing soil had been completely disassociated forming very large free gas zones in the bed soil beneath the relatively impermeable hydrate saturated topsoil (just do some Google searchers to see that soil saturated with hydrates is relatively impermeable to free gas).  This would be an extremely large volume of free gas the affect of which would be easily seen in the paleo-record of previous times that the EAIS began to retreat (or even melt totally), but no such record has been reported.

- Even if all of the methane hydrate in the soil was disassociated so that free gas from the bed soil was in direct contact with the underside of the EASI; you should realize that the methane hydrates are more stable than normal ice at these pressures; therefore, any amount of geotechnical heat sufficient to release the methane would cause a considerable amount of basal ice melting; which has not been reported yet, and again there is no paleo-record of any such massive about of EAIS basal melting occurring in the past.

- Lastly, you yourself (today) in the Arctic Sea Ice Blog note that only a relatively thin layer of Arctic Sea Ice is sufficient to trap free methane gas below it for at least months, no matter how fractured the sea ice might be.  Now, with thousands of meters of ice thickness in the EAIS there are no large factures in the ice sheet comparable to those in the Arctic Sea Ice, see the article below (that you already know about):

https://darchive.mblwhoilibrary.org/bitstream/handle/1912/4916/24-3_loose.pdf?sequence=1

Therefore, believe that Kallio's theory does not seem reasonable; and that the most likely source of the Antarctic atmospheric methane is from the marine environment.

Please keep up your great work on documenting methane releases, as I am certain that it is a growing problem (and the measured increase in Antarctic atmospheric methane is already sufficient to offset much of the ozone healing in Antarctica); nevertheless, I find Kallio's theory to be unacceptable from a physics point of view.

Best,
ASLR

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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #56 on: July 15, 2013, 02:09:15 AM »
I thought that I would post the atmospheric methane readings for July 13, 2013 indicating that concentration of atmospheric methane over Antarctica is continuing to decrease, as one might expect for a coastal marine source of methane emissions.
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #57 on: July 16, 2013, 02:08:39 AM »
I thought that I would note that at least until February 2013 the atmospheric methane concentration from NOAA's South Pole station (see the first attached image); follows the general shape of the atmospheric methane concentration from NOAA's Mauna Loa station (which is roughly typical of the global average, see the second attached image).
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #58 on: July 16, 2013, 10:18:15 PM »
A4R,

First, the following is another Antarctic Weather site that might have useful wind data for you:

http://www.antarctica.ac.uk/met/metlog/

Second, the attached image shows how the ozone hole forms a geopotential well in the atmosphere that can trap methane emitted from the ocean into the well over the continent.
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #59 on: July 20, 2013, 01:13:40 AM »
I thought that I should note that the attached figure shows that the atmospheric methane content is higher than last week.
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #60 on: July 24, 2013, 02:41:53 PM »
I do not have time to provide a reference, but I have read that as atmospheric humidity increases with global warming, the amount of high troposphere ice particles will increase, and that as there ice particles generally serve to reduce the rate of methane oxidation; this iimplies that with increasing global warming, the global warming potential, GWP, of the methane in the atmosphere over the Antarctic will increase.
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #61 on: July 24, 2013, 04:53:12 PM »
As a follow-up to my immediately prior post; I provide a copy of the following Internet article which state: (a) when methane is oxidized in the upper atmosphere, it creates water molecules that then contribute to the formation of ice crystals in the upper atmosphere; which in turn contribute to the increased formation of Noctilucent clouds (NLCs); and (b) NLCs are being observed with increasing frequency in the Antarctic Atmosphere.  Therefore, as this thread notes that methane is becoming increasingly concentrated in the Antarctic Atmosphere, and as ice crystals (particles) are also becoming more concentrated over Antarctica; and as the interaction of methane molecules and ice crystals (particles) increase the global warming potential, GWP, of methane; I believe that this constitutes as positive feedback mechanism that will contribute to accelerated ice mass loss from Antarctic as global warming continues:

http://science.nasa.gov/science-news/science-at-nasa/2013/07jun_nlcs/

"June 7, 2013:  Every summer, something strange and wonderful happens high above the north pole.  Ice crystals begin to cling to the smoky remains of meteors, forming electric-blue clouds with tendrils that ripple hypnotically against the sunset sky.  Noctilucent clouds—a.k.a. "NLCs"--are a delight for high-latitude sky watchers, and around the Arctic Circle their season of visibility is always eagerly anticipated.
News flash: This year, NLCs are getting an early start. NASA's AIM spacecraft, which is orbiting Earth on a mission to study noctilucent clouds, started seeing them on May 13th.
"The 2013 season is remarkable because it started in the northern hemisphere a week earlier than any other season that AIM has observed," reports Cora Randall of the Laboratory for Atmospheric and Space Physics at the University of Colorado. "This is quite possibly earlier than ever before."

The early start is extra-puzzling because of the solar cycle.  Researchers have long known that NLCs tend to peak during solar minimum and bottom-out during solar maximum—a fairly strong anti-correlation.  "If anything, we would have expected a later start this year because the solar cycle is near its maximum," Randall says. "So much for expectations."
For sky watchers, this means it's time to pay attention to the sunset sky, where NLCs are most often seen.  An early start could herald brighter clouds and wider visibility than ever before.
Noctilucent clouds were first noticed in the mid-19th century after the eruption of super-volcano Krakatoa. Volcanic ash spread through the atmosphere, painting vivid sunsets that mesmerized observers all around the world.  That was when the NLCs appeared. At first people thought they must be some side-effect of the volcano, but long after Krakatoa's ash settled the noctilucent clouds remained.
"They've been with us ever since," says Randall.  "Not only that, they are spreading."
When AIM was launched in 2007, the underlying cause of NLCs was still unknown. Researchers knew they formed 83 km above Earth's surface where the atmosphere meets the vacuum of space--but that's about all.  AIM quickly filled in the gaps.
"It turns out that meteoroids play an important role in the formation of NLCs," explains Hampton University Professor James Russell, the principal investigator of AIM. "Specks of debris from disintegrating meteors act as nucleating points where water molecules can gather and crystallize."
NLCs appear during summer because that is when water molecules are wafted up from the lower atmosphere to mix with the "meteor smoke." That is also the time when the upper atmosphere is ironically coldest.
Back in the 19th century, NLCs were confined to high latitudes.  You had to go to Alaska or Scandinavia to see them.  In recent years, however, they have been sighted as far south as Utah, Colorado, and Nebraska. Some researchers believe that the spread of NLCs is a sign of climate change.
One of the greenhouse gases that has become more abundant in Earth's atmosphere since the 19th century is methane.  "When methane makes its way into the upper atmosphere, it is oxidized by a complex series of reactions to form water vapor," says Russell. "This extra water vapor is then available to grow ice crystals for NLCs."
The early start of the 2013 season appears to be caused by a change in atmospheric “teleconnections.”
“Half-a-world away from where the northern NLCs are forming, strong winds in the southern stratosphere are altering global circulation patterns,” explains Randall. "This year more water vapor is being pushed into the high atmosphere where NLCs love to form, and the air there is getting colder."
"All of this has come as an interesting surprise for us," notes Russell.  "When we launched AIM, our interest was in the clouds themselves.  But now NLCs are teaching us about connections between different layers of the atmosphere that operate over great distances. Our ability to study these connections will surely lead to new understanding about how our atmosphere works.""
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prokaryotes

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Re: Antarctic Methane Concentrations
« Reply #62 on: July 27, 2013, 01:36:34 AM »
I collected some data and assembled some input and theories about methane origin  (also from this thread)

East Antarctic Methane Emissions
http://climatestate.com/magazine/2013/07/east-antarctic-methane-emissions/
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #63 on: July 27, 2013, 02:07:03 AM »
Prokaryotes,

Thank you for the quote; however, since I made that quote; I now believe that not only may methane be venting from marine methane hydrates near the Kerguelen Plateau, but additionally from many other Antarctic continental shelves (all around the continent) where warm CDW is intruding on to the continental shelves (particularly in to troughs on the continental shelves).  Such dispersed methane emissions would be difficult to see at sea level by satellite; but when accumulated higher up (from about 400 mb to 600 mb) over the East Antarctic by the concave shape of the atmospheric geopotential height caused by the ozone hole and local GHG (including the methane) over Antarctica.  As I have noted in prior posts, I believe that the cold temperatures and the increasing formation of ice crystals in the atmosphere high over Antarctica reduces the rate of oxidation of the methane, thus allowing lower concentrations to accumulate, just as they do in the Arctic.

Best,
ASLR
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prokaryotes

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Re: Antarctic Methane Concentrations
« Reply #64 on: July 27, 2013, 02:11:56 AM »
Ok, i updated the quote from you in above linked article. Thanks for your input AbruptSLR.
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prokaryotes

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Re: Antarctic Methane Concentrations
« Reply #65 on: July 27, 2013, 01:34:47 PM »
Are these methane readings through perforations in the rocky to ice layer on higher elevations? Can these gas molecules penetrate-vent through the ice sheet on higher elevation or through perforations - are there any surface layer to bedrock layer type of features in these area recorded?

Update
Added commentary by Leonid Yurganov and AbruptSLR's Katabatic winds image to the article (linked above).

Re Katabatic winds:
Quote
In a few regions of continental Antarctica the snow is scoured away by the force of the katabatic winds, leading to "dry valleys" (or "Antarctic oasis") such as the McMurdo Dry Valleys. Since the katabatic winds are descending, they tend to have a low relative humidity which desiccates the region. Other regions may have a similar but lesser effect, leading to "blue ice" areas where the snow is removed and the surface ice evaporates, but is replenished by glacier flow from upstream.
http://en.wikipedia.org/wiki/Katabatic_wind

I have read that as atmospheric humidity increases with global warming, the amount of high troposphere ice particles will increase, and that as there ice particles generally serve to reduce the rate of methane oxidation; this iimplies that with increasing global warming, the global warming potential, GWP, of the methane in the atmosphere over the Antarctic will increase.

Relevant
Quote
There are two driving forces behind the change in stratospheric moisture. Increasing emissions of methane are transformed into water in the stratosphere by chemical reactions. This can account for about a third of the observed increase in moisture there.

In addition, there is a greater transport of water from the lower atmosphere, which happens for several reasons. First of all, more water may be available in the lower atmosphere to be carried up. Warmer air holds more water vapor than colder air, so global warming will make the lower atmosphere wetter. Another possibility is that air is carried up more rapidly into the stratosphere. Climate models indicate that greenhouse gases such as carbon dioxide and methane may enhance the transport of air from the lower atmosphere up into the stratosphere. Additionally, the coldest temperature through which the air passes could change, which would alter the amount of water that freezes out along the way.
http://www.giss.nasa.gov/research/briefs/shindell_05/

Ofc the pole is a special spot though it might differ there.
« Last Edit: July 27, 2013, 03:57:03 PM by prokaryotes »
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AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #66 on: July 27, 2013, 05:58:50 PM »
Prokaryotes,

I will provide the following responses in the limited time available to me:

First, ice is both brittle (so it cracks) and viscous (so it flows like honey); thus as glaciers flow towards the ocean they deform, which generates internal heat, which causes internal melting, which can create some volumes which if created in sufficiently volumes (due to sufficiently high ice velocities) will rain down through microcracks to add to the volume of the system of subglacial basal melt water hydrological system of subglacial lakes, streams, swamps, etc.  Therefore, the hydrostatic pressures with the subglacial hydrological systems are about equal to pressures associated with the weight of the height of the ice in that particular area (otherwise the weight of the ice above say a subglacial lake would squeeze the subglacial water out of the subglacial lake (which can occur when the seal is broke linking the subglacial water to the ocean).  As Sidd notes subglacial melt water can and regularly does flow uphill (say up out of the BSB) just like water inside of a steel pipe can and does flow up to the top of a multi-story building, because the ice above the subglacial melt water forms a seal (including the seal provided by the internal melt water caused by internal friction that is filling any microcracks in the glaciers caused by internal deformations.  Now if the ice forms a seal to the water it also forms a seal for most any methane gas that might be trying to vent upwards from the East Antarctic crust; and more importantly, methane hydrates are more stable than ice under pressure; thus any methane gas trying to flow upwards through water filled microcracks in the glacier would form methane hydrates, thus effectively sealing the microcracks.  Therefore, as I told A4R and now I am telling you, I absolutely do not believe that the atmospheric methane measured over East Antarctica  is venting up through the several kilometer thick semi-viscous EAIS.

Second, as you have noted methane hydrates can form beneath Antarctic glaciers (due to biological processes); and as in the past 10,000 to 30,000 years glaciers use to be resting on almost all of the Antarctic continental shelves but has now retreated; therefore, you must believe that there are substantial quantities of methane hydrates in the sediments of the Antarctic continental shelves (just like you must believe is the case for the East Siberian Arctic Shelf, ESAS, in the Arctic).  Thus, it is much more logical to believe that as the warm CDW flows increasingly onto the Antarctic continental shelves, troughs and submerged plateaus, that the warm CDW would destabilize sufficient amounts of the methane hydrates in the seafloor sediment to cause local slope stability failures (submerged landslides) along the sides of the troughs, plateaus, and shelf/slope breaks, that would release sufficient quantities of methane gas that they could float to the surface before being re-absorbed by the ocean water (which is not saturated with methane), as is postulated by the Clathrate Gun Hypothesis (see my other posts on this topic, or Google it). 

Third, once vented from the numerous small subsea landsides around the perimeter of the Antarctia seafloor, I believe that this methane floats up onto the shoulder of the atmospheric geopotential height concave topology, where winds circulate towards the center of East Antarctica, where during the austral fall and winter months the lack of sunlight reduces the rate of methane oxidation sufficiently for significant quantities of methane to accumulate (as is the case in the Arctic for the Fall and Winter).

Fourth, you point out that Katabatic winds flow down from the center of East Antarctica and out towards the coast, and that the Katabatic wind is dry (implying that you think that the wind blows out from the center of Antarctica and thus the wind could never carry methane from the perimeter of Antarctica towards the center; which is incorrect, as I have stated above that the methane emissions around the perimeter would float up first and then be drawn into the center of Antarctica by the same vacuum caused by the air flowing down from the center of Antarctica that creates the Katabatic winds in the first place (see the figure in my post above in this thread).  The fact that the Katabatic wind is dry is because any moisture in the upper atmosphere over central Antarctica is so cold that it transformed into ice crystals (that serve to protect the methane from rapid oxidation), so that when the Katabatic wind decends they are carrying ice crystals and snow rather than water.

The complex nature of the Antarctic is why this is a playground for denialist to say anything that they want, without risk of being exposed.  Therefore, it is important to get the true story straight, because in any non-linear system small initial differences can result in large eventual differences.

Best,
ASLR
« Last Edit: May 13, 2014, 10:03:50 PM by AbruptSLR »
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Re: Antarctic Methane Concentrations
« Reply #67 on: July 30, 2013, 01:16:38 PM »
Identification and control of subglacial water networks under Dome A, Antarctica

Quote
“Subglacial water in continental Antarctica forms by melting of basal ice due to geothermal or frictional heating. The water system in the Gamburtsev Subglacial Mountains reoccupies a system of alpine overdeepenings created by valley glaciers in the early growth phase of the East Antarctic Ice Sheet. The networks follow valley floors either uphill or downhill depending on the gradient of the ice sheet surface. In cases where the networks follow valley floors uphill they terminate in or near plumes of freeze-on ice, indicating source to sink transport within the basal hydrologic system. Because the ice surface determines drainage direction within the bed-constrained network, the system is bed-routed but surface-directed.”
http://adsabs.harvard.edu/abs/2013JGRF..118..140W

Not sure if i understand this correctly but maybe basal melt and following uphill drainage is transporting melted methane hydrates to the surface?
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Re: Antarctic Methane Concentrations
« Reply #68 on: July 30, 2013, 04:21:35 PM »
AbruptSLR,

Thanks for all your work on Antarctic methane and the compilation of sources.

Another new tool has been added to methanetracker.org, that is the breakdown of CH$ concentrations into three display layers:

1750-1850 ppb
1850-1950 ppb
1950+ ppb

This function is retroactive to January 2013, similar to the macro function.

Also, the reporting has been updated.

A4R

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Re: Antarctic Methane Concentrations
« Reply #69 on: July 30, 2013, 11:02:35 PM »
A4R,

Thanks for your untiring work to bring the hazards of methane emissions to a broader audience. 

Separately, I provide the following phase diagram for natural gas hydrates; which indicates that even if pure methane were being introduced into the melt water in essentially any portion of the AIS subglacial hydrological system; the pressure within such basal melt water would most likely  (almost certainly) be sufficiently high to cause such methane gas to recombine with the melt water in order to form natural gas hydrates before the gas could reach the atmosphere.  As a side note the Gas Gravity is the weight of mole of the natural gas in question divided by the weight of a mole of air.
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Re: Antarctic Methane Concentrations
« Reply #70 on: July 31, 2013, 05:13:51 PM »
The region of apparently elevated CH4 concentrations over East Antarctica is coincident with high elevation and coldest temperatures.

A very similar pattern is observed over the higher elevations of N. Greenland around 2-27-13.


Before considering increasingly unlikely emission and/or collection scenarios, can it be verified that we aren't looking at an instrumental artifact?
« Last Edit: July 31, 2013, 05:20:57 PM by no1der »

AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #71 on: July 31, 2013, 06:27:21 PM »
no1der,

A4R is probably better qualified to respond about the validity of the instrument readings; however, at the NOAA satellite readings have been widely reviewed it is my opinion that due to the very cold/dark conditions in the atmosphere over East Antarctica during the austral winter, that the continuing measurement of methane around 500 mb altitude, is more of an indication that the rate of methane oxidation and dispersal is so low that we are seeing much the same methane molecules for a long time, rather than seeing large emissions from some unlikely emission scenario.  Again, we should be aware that the conditions in the atmosphere over Antarctica are more favorable for concentrating methane during the austral winter than is the case for the Arctic during the winter, and we should note be unduly swayed by prior Arctic experience when evaluating the measured Antarctic situation.

Best,
ASLR
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Re: Antarctic Methane Concentrations
« Reply #72 on: July 31, 2013, 08:07:48 PM »
I raise the question about instrumental artifact because elevated apparent CH4 concentrations can be seen over interior N. Greenland in early to mid Jan, and late Feb to early Mar 2013. Looking at the Summit, GL temperature history, these were the coldest periods of the winter, with weekly mean temperatures in the -40's F and average minima in the -50's F. Warmer intervals seem not to show the apparent methane anomalies. (Eyeballing methane tracker.org and http://www.wunderground.com/history/wmo/04416/2013/2/27/WeeklyHistory.html, absent a rigorous work-up). One could propose a T-dependent mechanism but before doing so it might be better to rule out some sort of instrumental or measurement artifact.

Noting that apparent methane anomalies are showing over Greenland at high elevation on the ice sheet and coincident with surface temperatures of ca. -50F or less, one might fairly wonder if the remarkably well-defined and persistent periphery of the apparent Antarctic methane anomalies does not circumscribe similar conditions.


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Re: Antarctic Methane Concentrations
« Reply #73 on: July 31, 2013, 08:49:42 PM »
no1der,

Certainly, at high altitudes over Greenland in the coldest parts of winter the chemical oxidation of methane is also slowed down, which should also allow methane to accumulate until a changing weather pattern blows the methane away.  Typically, it is colder still in Antarctica (in the austral winter) and the weather is also more stable; which might explain why the methane concentrations over East Antarctica appear to be both bigger and longer lasting than over Greenland (assuming that the satellite instrument is working well).

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ASLR
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Re: Antarctic Methane Concentrations
« Reply #74 on: August 07, 2013, 11:44:52 PM »
The following reference gives an idea of the complexities of determining the lifetime of methane based on atmospheric chemistry (the weblink leads to a free pdf of the paper):

http://www.atmos-chem-phys.net/13/5277/2013/acp-13-5277-2013.pdf

Naik, V., A. Voulgarakis, A.M. Fiore, L.W. Horowitz, J.-F. Lamarque, M. Lin, M.J. Prather, P.J. Young, D. Bergmann, P.J. Cameron-Smith, I. Cionni, W.J. Collins, S.B. Dalsøren, R. Doherty, V. Eyring, G. Faluvegi, G.A. Folberth, B. Josse, Y.H. Lee, I.A. MacKenzie, T. Nagashima, T.P.C. van Noije, D.A. Plummer, M. Righi, S.T. Rumbold, R. Skeie, D.T. Shindell, D.S. Stevenson, S. Strode, K. Sudo, S. Szopa, and G. Zeng, 2013: Preindustrial to present day changes in tropospheric hydroxyl radical and methane lifetime from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). Atmos. Chem. Phys., 13, 5277-5298, doi:10.5194/acp-13-5277-2013.

"We have analysed time-slice simulations from 17 global models, participating in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), to explore changes in present-day (2000) hydroxyl radical (OH) concentration and methane (CH4) lifetime relative to preindustrial times (1850) and to 1980. A comparison of modeled and observation-derived methane and methyl chloroform lifetimes suggests that the present-day global multi-model mean OH concentration is overestimated by 5 to 10% but is within the range of uncertainties. The models consistently simulate higher OH concentrations in the Northern Hemisphere (NH) compared with the Southern Hemisphere (SH) for the present-day (2000; inter-hemispheric ratios of 1.13 to 1.42), in contrast to observation-based approaches which generally indicate higher OH in the SH although uncertainties are large. Evaluation of simulated carbon monoxide (CO) concentrations, the primary sink for OH, against ground-based and satellite observations suggests low biases in the NH that may contribute to the high north–south OH asymmetry in the models. The models vary widely in their regional distribution of present-day OH concentrations (up to 34%). Despite large regional changes, the multi-model global mean (mass-weighted) OH concentration changes little over the past 150 yr, due to concurrent increases in factors that enhance OH (humidity, tropospheric ozone, nitrogen oxide (NOx) emissions, and UV radiation due to decreases in stratospheric ozone), compensated by increases in OH sinks (methane abundance, carbon monoxide and non-methane volatile organic carbon (NMVOC) emissions). The large inter-model diversity in the sign and magnitude of preindustrial to present-day OH changes (ranging from a decrease of 12.7% to an increase of 14.6%) indicate that uncertainty remains in our understanding of the long-term trends in OH and methane lifetime. We show that this diversity is largely explained by the different ratio of the change in global mean tropospheric CO and NOx burdens (ΔCO/ΔNOx, approximately represents changes in OH sinks versus changes in OH sources) in the models, pointing to a need for better constraints on natural precursor emissions and on the chemical mechanisms in the current generation of chemistry-climate models. For the 1980 to 2000 period, we find that climate warming and a slight increase in mean OH (3.5±2.2%) leads to a 4.3±1.9% decrease in the methane lifetime. Analysing sensitivity simulations performed by 10 models, we find that preindustrial to present-day climate change decreased the methane lifetime by about four months, representing a negative feedback on the climate system. Further, we analysed attribution experiments performed by a subset of models relative to 2000 conditions with only one precursor at a time set to 1860 levels. We find that global mean OH increased by 46.4±12.2% in response to preindustrial to present-day anthropogenic NOx emission increases, and decreased by 17.3±2.3%, 7.6±1.5%, and 3.1±3.0% due to methane burden, and anthropogenic CO, and NMVOC emissions increases, respectively."
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Re: Antarctic Methane Concentrations
« Reply #75 on: August 08, 2013, 12:18:34 AM »
The linked reference (the link provides a free pdf) discusses factors that influence the radiative forcing potential for methane:

http://www.atmos-chem-phys.net/13/4907/2013/acp-13-4907-2013.html


Voulgarakis, A., D.T. Shindell, and G. Faluvegi, 2013: Linkages between ozone depleting substances, tropospheric oxidation and aerosols. Atmos. Chem. Phys., 13, 4907-4916, doi:10.5194/acp-13-4907-2013.

Coupling between the stratosphere and the troposphere allows changes in stratospheric ozone abundances to affect tropospheric chemistry. Large-scale effects from such changes on chemically produced tropospheric aerosols have not been systematically examined in past studies. We use a composition-climate model to investigate potential past and future impacts of changes in stratospheric ozone depleting substances (ODS) on tropospheric oxidants and sulfate aerosols. In most experiments, we find significant responses in tropospheric photolysis and oxidants, with small but significant effects on methane radiative forcing. The response of sulfate aerosols is sizeable when examining the effect of increasing future nitrous oxide (N2O) emissions. We also find that without the regulation of chlorofluorocarbons (CFCs) through the Montreal Protocol, sulfate aerosols could have increased by 2050 by a comparable amount to the decreases predicted due to relatively stringent sulfur emissions controls. The individual historical radiative forcings of CFCs and N2O through their indirect effects on methane (-22.6 mW/m2 for CFCs and -6.7 mW/m2 for N2O) and sulfate aerosols (-3.0 mW/m2 for CFCs and +6.5 mW/m2 for N2O when considering the direct aerosol effect) discussed here are non-negligible when compared to known historical ODS forcing. Our results stress the importance of accounting for stratosphere-troposphere, gas-aerosol and composition-climate interactions when investigating the effects of changing emissions on atmospheric composition and climate."
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Re: Antarctic Methane Concentrations
« Reply #76 on: August 10, 2013, 01:12:06 AM »
The attached NOAA image of atmospheric methane concentrations shows that the concentrations over Antarctica are lower than one to two weeks ago; which I believe adds support to my previously stated opinion that this methane is of marine origins (possibly from warm CDW melting submerged permafrost on the Antarctic continental shelves, thus releasing the gas previously trapped below the once relatively impermeable permafrost); in a manner similar to that occurring in the Northern Hemisphere (but shifted by about one half year in time).
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Re: Antarctic Methane Concentrations
« Reply #77 on: August 20, 2013, 12:09:04 AM »
A4R,

I finally got access to a Chrome system and visited the www.methanetracker.og website, and I noted how much methane gas emissions that the tracker shows over the Southern Ocean that fall with the geopotential well shown in my post #58 of this thread.  Thus it is easy to image that these marine methane emissions could slowly find their way down to the bottom of the geopotential well, directly over Eastern Antartica.

Best,
ASLR
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Re: Antarctic Methane Concentrations
« Reply #78 on: September 07, 2013, 09:07:42 PM »
The following abstract is taken from the proceedings of the following IGSOC sponsored symposia.  This abstract provides a valuable update on the important topic methane generating microbes in the sediment beneath Antarctic glaciers/ice-sheets.  While not specific projections are made in the abstract, the abstract cites that further research will likely lead to new insights in this high risk factor for increasing radiative forcing as the Antarctic Ice Sheet retreats with time:


International Symposium on Changes in Glaciers and Ice Sheets: observations, modelling and environmental interactions; 28 July–2 August; Beijing, China; Contact: Secretary General, International Glaciological Society


http://www.igsoc.org/symposia/2013/beijing/proceedings/procsfiles/procabstracts_62.htm



Microbial diversity and potential methanogenic activity in Antarctic subglacial sediment Wenkai YAN, Yu ZHANG, Xiang XIAO, Bo SUN, Yinke DOU, Hongmei MA
Corresponding author: Hongmei Ma
Corresponding author e-mail: mahongmei@pric.gov.cn
"The subglacial ecosystem has been recognized as an environment with considerable methanogenic activity and therefore has a significant impact on the global methane budget and is sensitive to climate change (Tung, Bramall and others, 2005). Although the presence and diversity of methanogens have been reported in a few subglacial environments (Stibal, Wadham and others, 2012), the in situ microbial activity is as yet insufficiently envisaged. Moreover, the responses of the main microbial players to changes in geochemical environments, e.g. as glaciers recede or advance, have not been well studied due to technical difficulties in sampling and cultivation. In this study, we attempted to answer the above questions by applying an integrated approach, including molecular analysis and in vitro simulation, to sediment samples from Antarctic glaciers. 16S rRNA-based diversity analysis revealed that Euryarchaeota is the only phylum detected while most of the Archaea found are of the Methanomicrobia class. Furthermore, a phylogenetic tree based on the functional gene (mcrA gene, the terminal enzyme complex in the methane generation pathway, which is a specific marker for methanogen) was constructed. Results showed that the methanogens from Antarctic subglacial environments are more similar to methanogens reported in freshwater sediment than to those from polar environments. These results provide us with evidence on the potential substrate utilization of subglacial methanogens. With this in mind, we can further incubate the sediment samples in the simulated conditions to estimate the in situ and potential microbial activities. Therefore, we will obtain a better understanding of the effect of glacier recession on the subgalcial ecosystem. This study will also help us to explore the evolutional process and cold-adaptation mechanisms of methanogenic microorganisms."
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Re: Antarctic Methane Concentrations
« Reply #79 on: January 28, 2014, 01:03:10 AM »
The attached image from NOAA (see link), presents the methane flask measurements from the South Pole atmosphere; which indicates that indeed methane concentrations were trending upward in 2013 as compared to earlier data:


http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts%5dhttp://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts
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Re: Antarctic Methane Concentrations
« Reply #80 on: March 17, 2014, 07:37:11 AM »
The attached image (from the linked NOAA source) shows atmospheric methane concentrations  measured at the South Pole by flasks, through January 2014

http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts

This update from the last post shows that atmospheric methane concentrations at the South Pole are continuing to increase linearly.
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Re: Antarctic Methane Concentrations
« Reply #81 on: May 13, 2014, 10:15:32 PM »
In multiple posts in this thread I have stated my concern that underwater methane hydrates may be dissociating in relatively shallow continental shelf waters (due to increases in water temperatures associated with AGW) in the Southern Hemisphere and then been transported by winds into the Antarctic atmosphere where they tend to accumulated in the austral winter due to the lower temperatures in that timeframe.  The following link, and quote, references just possible methane source of the coast of New Zealand in just 200m of water:


http://www.stuff.co.nz/environment/10039610/Methane-field-discovered-off-Gisborne-coast

Quote: "A "huge network" of frozen methane and methane gas has been discovered in ocean sediments 20 kilometres to 50km off Gisborne.
A joint New Zealand-German research team found 99 gas flares in a 50-square kilometre area, venting in columns up to 250 metres high, the National Institute of Water and Atmospheric Research (Niwa) said.
Methane was also found building up beneath a large landslide and being released along the landslide margin, and there were indications of large areas of methane hydrates - ice-like frozen methane - below the sea floor.
The discoveries were made by a 16-member team using state-of-the-art seismic and echosounder technology on board the Niwa research vessel Tangaroa.
The concentration of sea floor gas vents was the densest known off the New Zealand coast, and the vents were in much shallower water than usual.
Venting usually happened around a depth of 800m on large ridges in the middle of the continental slope, Niwa marine geologist and voyage leader Dr Joshu Mountjoy said.
In this case venting was going on along the edge of the shelf in as little as 200m of water.
The work is part of a larger project focused on the interaction between gas hydrates and and slow-moving active landslides. The area surveyed was known to have large active landslides, up to 15km long and 100m thick.
Researchers were also hoping to understand whether some methane was reaching the atmosphere, rather than being mixed up in the water column and consumed by biological processes as normally happened, Mountjoy said.
"Methane is a very effective greenhouse gas and seabed methane release has the potential to dramatically alter the earth's climate," he said.
"As ocean temperatures change the methane hydrate system has the potential to become unstable."
It would be interesting to find out whether global warming was changing the ocean system off Gisborne and causing more methane expulsion than previously. Higher ocean temperatures could change conditions so ice could turn back into a gas.
It remained to be seen whether the area off Gisborne was sensitive to climate change, Mountjoy said.
"We may be entering into a situation where global climate change is influencing the methane hydrate system."
The researchers were also trying to understand what caused the large, slow landslides in the area.
In a recently submitted scientific paper they proposed the landslides might be the sea floor equivalent of glaciers, with frozen methane rather than water ice. Alternatively pressurized gas could be causing landslides to move down slope."

See also the attached image of the methane gas leaks and the information at the following link:

http://www.niwa.co.nz/news/joint-new-zealand-german-3d-survey-reveals-massive-seabed-gas-hydrate-and-methane-system

Also, to state the obvious, if the water depth is about 200-m and the column of methane bubbles in the water are about 250m tall, then a significant about of methane must be reaching the atmosphere.
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Re: Antarctic Methane Concentrations
« Reply #82 on: September 13, 2014, 04:35:21 PM »
With a nod to Laurent who provided the link at the bottom of this post in the "What new in Antarctica?" thread; I thought that it would be a good idea to cross-link the reference below into this "Antarctic Methane Concentration" thread.  The reference provides clear, first-hand, observations of methane seeps from glacially-formed fjords and troughs on the northern shelf of the island of South Georgia (in the Southern Ocean).  The other posts in this thread make it clear that this example of methane seeps from South Georgia is but one first-hand case of numerous seasonally activated (possibly by seasonal [and longer-term] changes in the ocean currents) sub-sea methane seeps in the Southern polar and sub-polar ocean regions.

M. Römer et al.: First evidence of widespread active methane seepage in the Southern Ocean, off the sub-Antarctic island of South Georgia; in Earth and Planetary Science Letters 403 (2014), S. 166 – 177.

http://www.sciencedirect.com/science/article/pii/S0012821X1400421X

Abstract: "An extensive submarine cold-seep area was discovered on the northern shelf of South Georgia during R/V Polarstern cruise ANT-XXIX/4 in spring 2013. Hydroacoustic surveys documented the presence of 133 gas bubble emissions, which were restricted to glacially-formed fjords and troughs. Video-based sea floor observations confirmed the sea floor origin of the gas emissions and spatially related microbial mats. Effective methane transport from these emissions into the hydrosphere was proven by relative enrichments of dissolved methane in near-bottom waters. Stable carbon isotopic signatures pointed to a predominant microbial methane formation, presumably based on high organic matter sedimentation in this region. Although known from many continental margins in the world's oceans, this is the first report of an active area of methane seepage in the Southern Ocean. Our finding of substantial methane emission related to a trough and fjord system, a topographical setting that exists commonly in glacially-affected areas, opens up the possibility that methane seepage is a more widespread phenomenon in polar and sub-polar regions than previously thought."

See also:
http://www.awi.de/en/news/press_releases/detail/item/greenhouse_gases_in_the_southern_ocean_first_evidence_of_active_methane_emission_at_the_antarctic_s/?tx_list_pi1
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Re: Antarctic Methane Concentrations
« Reply #83 on: January 27, 2015, 08:05:15 PM »
The attached South Pole atmospheric methane plot shows that the methane peak in November 2014 was above the recent (post 2006) trend line, see:

http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts]http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts

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Re: Antarctic Methane Concentrations
« Reply #84 on: August 07, 2015, 01:12:09 AM »
The first attached plot from the NOAA South Pole station with data through August 1 2015 shows that so far atmospheric methane concentrations are clearly accelerating with this past year's concentrations increasing at faster rate than the past several years.

The second attached NOAA satellite image of atmospheric methane concentration at 487 hPa on August 6 2015, shows that the concentrations about the Amundsen Sea Embayment, ASE, are over 2,000ppb (which is historically high); which makes me concerned that an El Nino driven influx of warm Circumpolar Deep Water, CDW, may be causing methane hydrates in the ASE seafloor to degrade at the highest rate of the satellite record.
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Re: Antarctic Methane Concentrations
« Reply #85 on: August 07, 2015, 03:32:32 PM »
The first attached plot from the NOAA South Pole station with data through August 1 2015 shows that so far atmospheric methane concentrations are clearly accelerating with this past year's concentrations increasing at faster rate than the past several years.

The second attached NOAA satellite image of atmospheric methane concentration at 487 hPa on August 6 2015, shows that the concentrations about the Amundsen Sea Embayment, ASE, are over 2,000ppb (which is historically high); which makes me concerned that an El Nino driven influx of warm Circumpolar Deep Water, CDW, may be causing methane hydrates in the ASE seafloor to degrade at the highest rate of the satellite record.

Well, you probably trace only artefacts in the satellite product, i.e. cloud fraction or temperature. Is there any peer-reviewed paper about the applicability of the retrieval method and its validation in Antarctica?  :-\

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Re: Antarctic Methane Concentrations
« Reply #86 on: August 07, 2015, 03:50:45 PM »
The first attached plot from the NOAA South Pole station with data through August 1 2015 shows that so far atmospheric methane concentrations are clearly accelerating with this past year's concentrations increasing at faster rate than the past several years.

The second attached NOAA satellite image of atmospheric methane concentration at 487 hPa on August 6 2015, shows that the concentrations about the Amundsen Sea Embayment, ASE, are over 2,000ppb (which is historically high); which makes me concerned that an El Nino driven influx of warm Circumpolar Deep Water, CDW, may be causing methane hydrates in the ASE seafloor to degrade at the highest rate of the satellite record.

Well, you probably trace only artefacts in the satellite product, i.e. cloud fraction or temperature. Is there any peer-reviewed paper about the applicability of the retrieval method and its validation in Antarctica?  :-\

While the second image in my post was by satellite, the first image is clearly labeled as reporting data gathered at the South Pole station by flasks.  Thus there is no question about the validity of the average flask trend line; however, if you want to read-up on the background of these plots, the first comes from the first link below, and the second image comes from the second link below:

http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts]http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts
 
http://www.ospo.noaa.gov/Products/atmosphere/soundings/iasi/index.html
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Re: Antarctic Methane Concentrations
« Reply #87 on: August 07, 2015, 04:06:07 PM »
The first attached plot from the NOAA South Pole station with data through August 1 2015 shows that so far atmospheric methane concentrations are clearly accelerating with this past year's concentrations increasing at faster rate than the past several years.

The second attached NOAA satellite image of atmospheric methane concentration at 487 hPa on August 6 2015, shows that the concentrations about the Amundsen Sea Embayment, ASE, are over 2,000ppb (which is historically high); which makes me concerned that an El Nino driven influx of warm Circumpolar Deep Water, CDW, may be causing methane hydrates in the ASE seafloor to degrade at the highest rate of the satellite record.

Well, you probably trace only artefacts in the satellite product, i.e. cloud fraction or temperature. Is there any peer-reviewed paper about the applicability of the retrieval method and its validation in Antarctica?  :-\

While the second image in my post was by satellite, the first image is clearly labeled as reporting data gathered at the South Pole station by flasks.  Thus there is no question about the validity of the average flask trend line; however, if you want to read-up on the background of these plots, the first comes from the first link below, and the second image comes from the second link below:

http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts]http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=SPO&program=ccgg&type=ts
 
http://www.ospo.noaa.gov/Products/atmosphere/soundings/iasi/index.html

I do trust the flask samples and was asking about a reference for the satellite retrieval in Antarctica. The IASI retrievals are provided with a quality flag. Have you ever looked at that?

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Re: Antarctic Methane Concentrations
« Reply #88 on: August 07, 2015, 04:35:10 PM »
I do trust the flask samples and was asking about a reference for the satellite retrieval in Antarctica. The IASI retrievals are provided with a quality flag. Have you ever looked at that?

The Infrared Atmospheric Sounding Interferometer (IASI) methane readings are reported four times a day, every day, and are subject to: source variations, atmospheric variations and instrument uncertainties; however, I am not interesting in tracking, or characterizing, these uncertainties.  If you want to, please do so.
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Re: Antarctic Methane Concentrations
« Reply #89 on: August 07, 2015, 04:42:28 PM »
I do trust the flask samples and was asking about a reference for the satellite retrieval in Antarctica. The IASI retrievals are provided with a quality flag. Have you ever looked at that?

The Infrared Atmospheric Sounding Interferometer (IASI) methane readings are reported four times a day, every day, and are subject to: source variations, atmospheric variations and instrument uncertainties; however, I am not interesting in tracking, or characterizing, these uncertainties.  If you want to, please do so.

If you are interested in real signals, i.e. the atmospheric methane variations, you have to average the data considering these uncertainties. Otherwise you only see noise and artefacts.

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Re: Antarctic Methane Concentrations
« Reply #90 on: August 07, 2015, 04:54:36 PM »
I do trust the flask samples and was asking about a reference for the satellite retrieval in Antarctica. The IASI retrievals are provided with a quality flag. Have you ever looked at that?

The Infrared Atmospheric Sounding Interferometer (IASI) methane readings are reported four times a day, every day, and are subject to: source variations, atmospheric variations and instrument uncertainties; however, I am not interesting in tracking, or characterizing, these uncertainties.  If you want to, please do so.

If you are interested in real signals, i.e. the atmospheric methane variations, you have to average the data considering these uncertainties. Otherwise you only see noise and artefacts.

I have used the eyeball method to track the variations in the IASI readings for about 2-years now, and in my eyeball's opinion these readings are trending upward at about the same pace as the flask readings from the South Pole Station.  Whether or not any individual IASI reading indicates a "Dragon's Breath" of methane hydrate degradation from the Southern Ocean, is just as much speculation as it is in the Arctic region (of which Jason Box reports many such possible isolated "Dragon's Breath" events).  So while I agree that the IASI should not be taken as "proof"; I think that they can be taken as an invitation for oceanographers to take more appropriate in-situ readings for possible methane emissions from the seafloor as the ASE marine glacier grounding lines retreat (thus exposing previously protected bed soil formations to warm CDW).
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seaice.de

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Re: Antarctic Methane Concentrations
« Reply #91 on: August 07, 2015, 05:12:00 PM »
I do trust the flask samples and was asking about a reference for the satellite retrieval in Antarctica. The IASI retrievals are provided with a quality flag. Have you ever looked at that?

The Infrared Atmospheric Sounding Interferometer (IASI) methane readings are reported four times a day, every day, and are subject to: source variations, atmospheric variations and instrument uncertainties; however, I am not interesting in tracking, or characterizing, these uncertainties.  If you want to, please do so.

If you are interested in real signals, i.e. the atmospheric methane variations, you have to average the data considering these uncertainties. Otherwise you only see noise and artefacts.

I have used the eyeball method to track the variations in the IASI readings for about 2-years now, and in my eyeball's opinion these readings are trending upward at about the same pace as the flask readings from the South Pole Station.  Whether or not any individual IASI reading indicates a "Dragon's Breath" of methane hydrate degradation from the Southern Ocean, is just as much speculation as it is in the Arctic region (of which Jason Box reports many such possible isolated "Dragon's Breath" events).  So while I agree that the IASI should not be taken as "proof"; I think that they can be taken as an invitation for oceanographers to take more appropriate in-situ readings for possible methane emissions from the seafloor as the ASE marine glacier grounding lines retreat (thus exposing previously protected bed soil formations to warm CDW).

Well, you could eyeball the images for another 10-years but you can't draw any valid conclusions if you ignore the uncertainties and quality flags. The eyeball method is just waste of time and misleading with this kind of noisy and biased satellite data. Perhaps try a scientific approach?

AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #92 on: August 07, 2015, 05:27:32 PM »
Well, you could eyeball the images for another 10-years but you can't draw any valid conclusions if you ignore the uncertainties and quality flags. The eyeball method is just waste of time and misleading with this kind of noisy and biased satellite data. Perhaps try a scientific approach?

As I stated previously, I am not interested in spending my time characterizing this signal noise and satellite bias; however, if you want to please do so.
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seaice.de

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Re: Antarctic Methane Concentrations
« Reply #93 on: August 07, 2015, 05:50:36 PM »
Well, you could eyeball the images for another 10-years but you can't draw any valid conclusions if you ignore the uncertainties and quality flags. The eyeball method is just waste of time and misleading with this kind of noisy and biased satellite data. Perhaps try a scientific approach?

As I stated previously, I am not interested in spending my time characterizing this signal noise and satellite bias; however, if you want to please do so.

If you do not care about the quality of the data you should better stop posting this kind of satellite images. These level 2 products "are provided only for the purposes of demonstrative and experimental use by qualified remote sensing researchers or experienced meteorologists and oceanographers" as NOAA/NESDIS clearly states on their website.

AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #94 on: August 07, 2015, 06:03:39 PM »
Well, you could eyeball the images for another 10-years but you can't draw any valid conclusions if you ignore the uncertainties and quality flags. The eyeball method is just waste of time and misleading with this kind of noisy and biased satellite data. Perhaps try a scientific approach?

As I stated previously, I am not interested in spending my time characterizing this signal noise and satellite bias; however, if you want to please do so.

If you do not care about the quality of the data you should better stop posting this kind of satellite images. These level 2 products "are provided only for the purposes of demonstrative and experimental use by qualified remote sensing researchers or experienced meteorologists and oceanographers" as NOAA/NESDIS clearly states on their website.

The satellite data that I have posted is absolutely not cherry-picked outliers.  Thus while I agree that these posted satellite image data by themselves do not make definitive statements; they can serve as reminders to individuals (scientists or otherwise) to look deeper into the question of the clearly increasing methane emission (clearly as indicated by the accompanying South Pole flask data); whether from subsea methane hydrate degradation; tropical rainforest distress; anthropogenic sources, or other sources.  So you can view them as reminders of a trend, or you can ignore them.
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Re: Antarctic Methane Concentrations
« Reply #95 on: August 16, 2015, 06:42:47 AM »
The first attached plot from the NOAA South Pole station with data through August 1 2015 shows that so far atmospheric methane concentrations are clearly accelerating with this past year's concentrations increasing at faster rate than the past several years.

The second attached NOAA satellite image of atmospheric methane concentration at 487 hPa on August 6 2015, shows that the concentrations about the Amundsen Sea Embayment, ASE, are over 2,000ppb (which is historically high); which makes me concerned that an El Nino driven influx of warm Circumpolar Deep Water, CDW, may be causing methane hydrates in the ASE seafloor to degrade at the highest rate of the satellite record.

thanks for sharing the info, aSLR.  while the satellite image isn't definitive, i agree that it's worth noting, particularly since atmospheric methane is so much higher than preindustrial levels and so under reported.  i find methane rise in general quite worrisome.  thanks for keeping us updated.  :)

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Re: Antarctic Methane Concentrations
« Reply #96 on: August 16, 2015, 12:56:11 PM »
The first attached plot from the NOAA South Pole station with data through August 1 2015 shows that so far atmospheric methane concentrations are clearly accelerating with this past year's concentrations increasing at faster rate than the past several years.

The second attached NOAA satellite image of atmospheric methane concentration at 487 hPa on August 6 2015, shows that the concentrations about the Amundsen Sea Embayment, ASE, are over 2,000ppb (which is historically high); which makes me concerned that an El Nino driven influx of warm Circumpolar Deep Water, CDW, may be causing methane hydrates in the ASE seafloor to degrade at the highest rate of the satellite record.

thanks for sharing the info, aSLR.  while the satellite image isn't definitive, i agree that it's worth noting, particularly since atmospheric methane is so much higher than preindustrial levels and so under reported.  i find methane rise in general quite worrisome.  thanks for keeping us updated.  :)

Totally agree. If we only wait for absolute verified sources of which all uncertainties are quantified, we'll be very late to recognize any trend, and we don't have that much time on our hands.

AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #97 on: January 11, 2016, 11:42:36 PM »
Per the attached NOAA plot of the South Pole atmospheric methane concentration through January 9, 2016, the methane concentrations clearly accelerated after August 1, 2015 (the low point of the red portion of the curve).  This is not a good sign.
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crandles

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Re: Antarctic Methane Concentrations
« Reply #98 on: January 12, 2016, 01:12:17 PM »
While 99 showed acceleration, that seems well after the 97/98 El Nino whereas this seems before current El Nino reached its peak so it seems hard to attribute it to just an El Nino effect.

Even so short term fluctuation or long term trend turning point?

Poles showing increases but Mauna Loa not
http://www.esrl.noaa.gov/gmd/webdata/iadv/ccgg/graphs/ccgg.MLO.ch4.1.none.discrete.all.png

I would guess it seems more likely to be regional sources becoming more active rather than local or global as there isn't likely to be much local sources or sinks near south pole.

Certainly concerning if it continues.


AbruptSLR

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Re: Antarctic Methane Concentrations
« Reply #99 on: January 12, 2016, 05:24:59 PM »
While 99 showed acceleration, that seems well after the 97/98 El Nino whereas this seems before current El Nino reached its peak so it seems hard to attribute it to just an El Nino effect.

Even so short term fluctuation or long term trend turning point?

Poles showing increases but Mauna Loa not

I would guess it seems more likely to be regional sources becoming more active rather than local or global as there isn't likely to be much local sources or sinks near south pole.

Certainly concerning if it continues.

I generally agree with your observations, and I note that a local source of methane near the South Pole seems particularly disturbing to me, if true, as any significant methane emissions from the Southern Ocean are most certainly not in any climate model forecasts for 2015.
« Last Edit: January 12, 2016, 05:38:45 PM by AbruptSLR »
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson