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ArcticMelt2

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Re: Arctic Methane Release
« Reply #1100 on: November 01, 2019, 07:57:19 PM »
Apologies for the duplicate post, I'm reposting this here (from the stupid questions thread) as I think it's a more appropriate thread.

I'm looking for recent methane concentration data from the Tiksi weather station, but the most recent data I can find on the NOAA website is over a year old.

Is the station still operational? Is NOAA still collecting this data? Or am I just being impatient?

But there's data from Barrow. This year is really different unprecedented methane emissions in the Arctic for all time observations (after 1984).

https://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=BRW&program=ccgg&type=ts
« Last Edit: November 01, 2019, 08:06:07 PM by ArcticMelt2 »

ArcticMelt2

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Re: Arctic Methane Release
« Reply #1101 on: November 01, 2019, 08:03:06 PM »
I note that the summer of 2019 in Barrow was the warmest during observations:



This is further proof that every record in positive temperatures in the Arctic leads to a record of methane emissions.

I noted in a neighboring topic that this area of Alaska has some of the largest coal reserves in the world. Coal is buried in permafrost, and its melting causes methane to be released from the coal. Methane often explodes and kills the miners in the coal mines.

Bugalugs

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Re: Arctic Methane Release
« Reply #1102 on: November 01, 2019, 10:52:08 PM »
The Barrow NOAA methane data is bizarre.

I note that a spike is not appearing at other sites, yet.

A burp, or the beginning of feedback acceleration?

Ken Feldman

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Re: Arctic Methane Release
« Reply #1103 on: November 01, 2019, 11:47:37 PM »
The Barrow NOAA methane data is bizarre.

I note that a spike is not appearing at other sites, yet.

A burp, or the beginning of feedback acceleration?

Or a quality control issue?  Notice that the last few months of data are in orange which means they haven't been validated through quality control yet.

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A smooth curve and long-term trend may be fitted to the representative measurements when sufficient data exist. Data shown in ORANGE are preliminary. All other data have undergone rigorous quality assurance and are freely available from GMD, CDIAC, and WMO WDCGG.

https://www.esrl.noaa.gov/gmd/dv/iadv/help/ccgg_details.html

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Warning: Preliminary data include the this group's most up-to-date data and have not yet been subjected to rigorous quality assurance procedures. Preliminary data viewed from this site are "pre-filtered" using tools designed to identify suspect values. Filtering is performed each time a data set containing preliminary data is requested. Filtering, however, cannot identify systematic experimental errors and will not be used in place of existing data assurance procedures. Thus, there exists the potential to make available preliminary data with systematic biases. In all graphs, preliminary data are clearly identified. Users are strongly encouraged to contact Dr. Pieter Tans, Group Chief (pieter.tans@noaa.gov) before attempting to interpret preliminary data.

kassy

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Re: Arctic Methane Release
« Reply #1104 on: November 02, 2019, 06:25:28 PM »
Basically all the orange is this year so they might only validate per year. If so i hope they do it in January.

I guess it´s a ´local burp´ and since the highest blue dot is only a bit lower then the highest orange dot and the process of measuring is automatic it probably will not change much after validation.

It is a logical progression from the rest of the series with last years conditions.

It´s a pity that we have no Tiksi data as Alumril noted.

PS: Alumril do you have any idea if there are russian sites with this sort of data?
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Lewis

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Re: Arctic Methane Release
« Reply #1105 on: November 04, 2019, 01:03:03 AM »
Igor Semiletov and 65 other scientists on board of a Russian vessel studying the Arctic waters have found that methane in the air over the ESS has up to nine times the global average, research also found that methane jets are shooting up from the seabed to the water’s surface.

https://www.cnn.com/2019/10/12/us/arctic-methane-gas-flare-trnd/index.html?no-st=1572824167

I’ve read some comments on this thread that methane doesn’t come up in the bubbles because due microorganisms eats most of the methane.

Has this understanding changed? Is there more methane being released now than in the past to the point that the microorganism are unable to consume most of the methane before it reaches the surface?

kassy

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Re: Arctic Methane Release
« Reply #1106 on: November 04, 2019, 02:55:23 PM »
I’ve read some comments on this thread that methane doesn’t come up in the bubbles because due microorganisms eats most of the methane.

It depends on the local circumstances. If the water column is very deep the methane will not reach the surface. The ESAS is very shallow so the methane comes up to the surface there. 

The change is not due to methane overwhelming microorganisms.
It is just a result of more warming in the area.

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Eastern Siberian Sea (ESS)
- The average open water for the year in the 1980's was circa 10 %. Since 2007 it has risen to over 20% in nearly all years.
- For the three minimum ice months Aug-Oct the open water percentage has risen from circa 15% for most of the 1980's to a highly variable 70% to 90% since 2007. In 2019 nearly 90%.
See post #2839 in the 2019 sea ice area and extent thread for the full version with graph.

This is a good start point:
Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf
https://www.mdpi.com/2076-3263/9/6/251/htm
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Ken Feldman

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Re: Arctic Methane Release
« Reply #1107 on: November 05, 2019, 08:19:44 PM »
Igor Semiletov and 65 other scientists on board of a Russian vessel studying the Arctic waters have found that methane in the air over the ESS has up to nine times the global average, research also found that methane jets are shooting up from the seabed to the water’s surface.

https://www.cnn.com/2019/10/12/us/arctic-methane-gas-flare-trnd/index.html?no-st=1572824167

I’ve read some comments on this thread that methane doesn’t come up in the bubbles because due microorganisms eats most of the methane.

Has this understanding changed? Is there more methane being released now than in the past to the point that the microorganism are unable to consume most of the methane before it reaches the surface?

Lewis,

The most recent studies still support the fact that most methane is consumed by microbes as it migrates up through the unfrozen sediment that overlays the thawing permafrost layers.  (In some cases, the permafrost is hundreds of meters below the unfrozen sediment, so when you see estimates of huge amounts of methane in permafrost, keep that in mind).  And if the methane is released from areas deeper than 30 meters, it doesn't reach the surface due to chemical reactions with the water.

Here's a link to a pre-published discussion paper from July 2019.  It has a good overview of the current science about methane escape from the ESAS.

https://pdfs.semanticscholar.org/0745/b28231ab3a1a33c47362b03da21d519924ca.pdf

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Assessing the potential for non-turbulent methane escape from the East Siberian Arctic Shelf
Matteo Puglini, Victor Brovkin, Pierre Regnier, and Sandra Arndt

Abstract.

East Siberian Arctic Shelf (ESAS) hosts large, yet poorly quantified reservoirs of subsea permafrost and associated gas  hydrates.  It  has  been  suggested  the  global-warming  induced  thawing  and  dissociation  of  these  reservoirs  is  currently releasing methane to the shallow shelf ocean and ultimately the atmosphere. However, the exact contribution of permafrost thaw  and  methane  gas  hydrate  destabilization  to  benthic  methane  efflux  from  the  warming  shelf  and  ultimately  methane-climate feedbacks remains controversial. A major unknown is the fate of permafrost and/or gas hydrate-derived methane as it migrates towards the sediment-water interface. In marine sediments, (an)aerobic oxidation reactions generally act as extremely efficient biofilters that often consume close to 100% of the upward migrating methane. However, it has been shown that a number of environmental conditions can reduce the efficiency of this biofilter, thus allowing methane to escape to the overlying ocean. Here, we used a reaction-transport model to assess the efficiency of the benthic methane filter and, thus, the potential for permafrost and/or gas hydrate derived methane to escape shelf sediments under a wide range of environmental conditions encountered on East Siberian Arctic Shelf. Results of an extensive sensitivity analysis show that, under steady state conditions, anaerobic oxidation of methane (AOM) acts as an efficient biofilter that prevents the escape of dissolved methane from shelf sediments  for  a  wide  range  of  environmental  conditions.  Yet,  highCH4 escape  comparable  to  fluxes  reported  from  mud-volcanoes is simulated for rapidly accumulating (sedimentation rate>0.7cm yr−1) and/or active (active fluid flow>6cmyr−1) sediments and can be further enhanced by mid-range organic matter reactivity and/or intense local transport processes, such as bioirrigation. In active settings, high non-turbulent methane escape of up to 19μmolCH4cm−2yr−1can also occur during a transient, multi-decadal period following the sudden onset of CH4 flux triggered by, for instance, permafrost thaw or hydrate destabilization. This "window of opportunity" arises due to the time needed by the microbial community to build up an efficient AOM biofilter. In contrast, seasonal variations in environmental conditions (e.g. bottom water SO2−4,CH4 flux) exert a negligible effect on CH4 efflux through the Sediment-Water Interface (SWI). Our results indicate that present and future methane efflux from ESAS sediments is mainly supported by methane gas and non-turbulent CH4 efflux from rapidly accumulating and/or active sediments (e.g. coastal settings, portions close to river mouths or submarine slumps). In particular active sites on the ESAS may release methane in response to the onset or increase of permafrost thawing or CH4 gas hydrate destabilization rates. Model results also reveal that AOM generally acts as an efficient biofilter for upward migrating CH4 under environmental conditions that are representative for the present-day ESAS with potentially important, yet unquantified implications for the Arctic ocean’s alkalinity budget and, thus, CO2 fluxes. The results of the model sensitivity study are used as a quantitative framework to derive first-order estimates of non-turbulent, benthic methane efflux from the Laptev Sea. We find that, under present day conditions, AOM is an efficient biofilter and non-turbulent methane efflux from Laptev Sea sediments does not exceed 1 GgCH4yr−1. As a consequence, we state that previously published estimates of fluxes from ESAS water into atmosphere cannot be supported by non-turbulent methane escape from the sediments, but require the build-up and preferential escape of benthic methane gas from the sediments to the atmosphere that matches or even exceeds such estimated fluxes.

The "methane fountain" reported on in October was a very rare event.

https://siberiantimes.com/other/others/news/first-pictures-and-video-of-the-largest-methane-fountain-so-far-discovered-in-the-arctic-ocean/

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‘It was a needle in a haystack chase, to find an exact place of a methane seep in dark sea waters, but we found it!

Quote
‘This was the most powerful seep I have ever observed. No one has ever recorded anything similar’ said head of the expedition Igor Semiletov, who has participated in 45 Arctic expeditions.

And it was pretty small.

Quote
The area of the fountain covered about five metres,



Lewis

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Re: Arctic Methane Release
« Reply #1108 on: November 06, 2019, 05:25:29 AM »
Thanks Ken for your detailed explanation, appreciate it.
Kassy, thanks for your reply as well.

wdmn

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Re: Arctic Methane Release
« Reply #1109 on: January 14, 2020, 09:13:20 AM »
Climate gas budgets highly overestimate methane discharge from Arctic Ocean

https://phys.org/news/2020-01-climate-gas-highly-overestimate-methane.html

The atmospheric concentration of methane, a potent greenhouse gas, has almost tripled since the beginning of industrialisation. Methane emissions from natural sources are poorly understood. This is especially the case for emissions from the Arctic Ocean.

The Arctic Ocean is a harsh working environment. That is why many scientific expeditions are conducted in the summer and early autumn months, when the weather and the waters are more predictable. Most extrapolations regarding the amount of methane discharge from the ocean floor, are thus based on observations made in the warmer months.

"This means that the present climate gas calculations are disregarding the possible seasonal temperature variations. We have found that seasonal differences in bottom water temperatures in the Arctic Ocean vary from 1.7°C in May to 3.5°C in August. The methane seeps in colder conditions decrease emissions by 43 percent in May compared to August." says oceanographer Benedicte Ferré, researcher at CAGE Centre for Arctic Gas Hydrate, Environment and Climate at UiT The Arctic University of Norway.

"Right now, there is a large overestimation in the methane budget. We cannot just multiply what we find in August by 12 and get a correct annual estimate. Our study clearly shows that the system hibernates during the cold season."

...

How methane will react in future ocean temperature scenarios is still unknown. The Arctic Ocean is expected to become between 3°C and a whopping 13°C warmer in the future, due to climate change. The study in question does not look into the future, but focuses on correcting the existing estimates in the methane emissions budget. However:

"We need to calculate the peculiarities of the system well, because the oceans are warming. The system such as this is bound to be affected by the warming ocean waters in the future," says Benedicte Ferré. A consistently warm bottom water temperature over a 12-month period will have an effect on this system.

"At 400 meters water depth we are already at the limit of the gas hydrate stability. If these waters warm merely by 1.3°C this hydrate lid will permanently lift, and the release will be constant," says Ferré.

kassy

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Re: Arctic Methane Release
« Reply #1110 on: January 14, 2020, 03:41:32 PM »
"This means that the present climate gas calculations are disregarding the possible seasonal temperature variations. We have found that seasonal differences in bottom water temperatures in the Arctic Ocean vary from 1.7°C in May to 3.5°C in August. The methane seeps in colder conditions decrease emissions by 43 percent in May compared to August." says oceanographer Benedicte Ferré, researcher at CAGE Centre for Arctic Gas Hydrate, Environment and Climate at UiT The Arctic University of Norway.

"Right now, there is a large overestimation in the methane budget. We cannot just multiply what we find in August by 12 and get a correct annual estimate. Our study clearly shows that the system hibernates during the cold season."


This is so blindingly obvious that i don´t think anyone actually working out emissions ever just extrapolates from august.

Read the abstract to compare. They made it overly simple for the journalists or something like that.

Reduced methane seepage from Arctic sediments during cold bottom-water conditions
https://www.nature.com/articles/s41561-019-0515-3
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Shared Humanity

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Re: Arctic Methane Release
« Reply #1111 on: January 14, 2020, 09:06:15 PM »
" We have found that seasonal differences in bottom water temperatures in the Arctic Ocean vary from 1.7°C in May to 3.5°C in August. The methane seeps in colder conditions decrease emissions by 43 percent in May compared to August.""


If I'm suppose to feel relieved that an increase in bottom water temperatures of less than 2C can increase methane emissions by 43%, I must be missing something.

Ken Feldman

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Re: Arctic Methane Release
« Reply #1112 on: January 22, 2020, 01:01:40 AM »
While the initial part of peer-reviewed science is to get your paper published in a peer-reviewed journal, it doesn't end there.  Once your paper is published, other scientists read and evaluate it and if they find mistakes, publish comments in the peer-reviewed journals.  Often, these comments don't get the same attention that the initial paper received.

For example the paper, "Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf" by Shakhova, Semiletov and Chuvilin, (S2019), got a lot of press when it was published.  It's been linked to upthread and there were also several posts linking the video interview that Dr. Shakova gave when the paper was published.

To date, no one has linked to the comment on the paper that corrects several of the mistakes in S2019.  Here it is.

https://www.mdpi.com/2076-3263/9/9/384/htm 

Quote

Geosciences 2019, 9(9), 384; https://doi.org/10.3390/geosciences9090384
Comment
Comment on “Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf”
by Brett F. Thornton 1,2,*, Marc C. Geibel 2,3,*, Patrick M. Crill 1,2, Christoph Humborg 2,3 and Carl-Magnus Mörth 1,2
1 Department of Geological Sciences, Stockholm University, 106 91 Stockholm, Sweden
2 Bolin Centre for Climate Research, 106 91 Stockholm, Sweden
3 Baltic Sea Centre, Stockholm University, 106 91 Stockholm, Sweden
*
Authors to whom correspondence should be addressed.
Received: 12 July 2019 / Accepted: 29 August 2019 / Published: 2 September 2019

  Abstract: The recent paper in Geosciences, “Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf” by Shakhova, Semiletov, and Chuvilin, (henceforth “S2019”), contains a number of false statements about our 2016 paper, “Methane fluxes from the sea to the atmosphere across the Siberian shelf seas”, (henceforth “T2016”). S2019 use three paragraphs of section 5 of their paper to claim methodological errors and issues in T2016. Notably they claim that in T2016, we systematically removed data outliers including data with high methane concentrations; this claim is false. While we appreciate that flawed methodologies can be a problem in any area of science, in this case, the claims made in S2019 are simply false. In this comment, we detail the incorrect claims made in S2019 regarding T2016, and then discuss some additional problematic aspects of S2019.

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Below are some additional concerns we have with S2019, not directly related to their discussion of T2016.

In the introduction, S2019 state: “This vast yet shallow region has recently been shown to be a significant modern source of atmospheric CH4, contributing annually no less than terrestrial Arctic ecosystems [19,20]”. Neither reference being cited here reports an annual emission flux of CH4 greater than that from terrestrial arctic ecosystems—which are dominated by wetlands. Arctic wetland emissions are estimated between 23–31 Tg of CH4 per year [13,14,15,16], exceeding the sea emission estimates provided in S2019’s references 19 and 20. Additionally, terrestrial Arctic ecosystem emissions include other freshwater systems, such that the total terrestrial CH4 emission easily exceeds the fluxes predicted in S2019’s references 19 and 20.

S2019 also state in the introduction that “Releases could potentially increase by 3–5 orders of magnitude, considering the sheer amount of CH4 preserved within the shallow ESAS seabed deposits and the documented thawing rates of subsea permafrost reported recently [22].” Reference 22 of S2019 does not support the assertion that ESAS CH4 releases could increase by 3–5 orders of magnitude, and the claim itself is unsupported and untenable. If we consider the largest “best estimate” of annual ESAS CH4 emission to the atmosphere published from Drs. Shakhova and Semiletov’s work [11], 17 Tg year−1, 3 orders of magnitude more is 17,000 Tg of CH4 per year, and five orders of magnitude is 1,700,000 Tg of CH4 per year, an absurd annual flux value, not only compared to the current annual emissions of CH4 from all sources (~555 Tg CH4 year−1, [17]), but the larger also vastly exceeds estimates of the entire global CH4 hydrate inventory (estimated at 1800 gigatonnes carbon, or ~239,400 Tg CH4) [18]. We also wonder if S2019 are conflating seawater-to-air fluxes with seafloor-to-seawater fluxes in this section. The text in S2019 is also unclear as to whether this postulated massive increase in flux applies to the entire ESAS, or some subsection, which is critical when determining how large future CH4 emissions might be. It may be helpful if S2019 reported their actual predicted flux, instead of a multiplication factor.

kassy

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Re: Arctic Methane Release
« Reply #1113 on: January 22, 2020, 06:13:50 PM »
Sometimes science can be annoying.  :)

Did not look into the first part.

Reference 22 of S2019 does not support the assertion that ESAS CH4 releases could increase by 3–5 orders of magnitude

I did actually miss the numbers for that too on the initial read.

The second bolded part is even more annoying. Because either someone screwed up or there is a severe miscommunication somewhere.

If we are really lazy and read orders of magnitude as doublings we get 68-17 is 51 Tg so nearly 10% extra on the global budget (which would go along with a rise from other sources).

I am not really interested in the maximum numbers (but i would not mind a more budget oriented paper).

Basically we know this methane release happens and it will increase as long as we increase our push.

And it will go together with the CO2 and CH4 wafting of the melting permafrost.

I am not looking toward future scenarios as much as seeing the current damage and thinking we should limit that. The old idea of preventing climate change was save the Arctic Sea Ice so in the long run Greenland would not melt too badly and the permafrost would remain a sink. And Antarctica would not be a thing ever.

So far we probably failed 1 no matter what we do, we will see what Ger reports about Greenland in the long term and probably arctic permafrost is already a net source not a sink.

And there is enough stuff happening in Antarctica.

This is not an isolated problem but just another feedback.
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kassy

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Re: Arctic Methane Release
« Reply #1114 on: February 05, 2020, 11:41:30 AM »
Less methane released from Arctic Ocean than previously believed

A new study, led by researchers at Stockholm university and published in Science Advances, now demonstrates that the amount of methane presently leaking to the atmosphere from the Arctic Ocean is much lower than previously claimed in recent studies.

...

A unique application of an established measurement technique

In their study, the researchers used direct measurements of the methane sea-to-air flux to determine how much methane is leaking from the eastern Arctic Ocean to the atmosphere. They used data from the 2014 SWERUS-C3 project, during which the Swedish icebreaker Oden crossed the eastern Arctic Ocean from Tromsø, Norway.

Although other researchers have calculated the sea-to-air flux before, this study used a unique measurement technique to measure the fluxes directly, and the authors believe their paper is the first to successfully apply this method from a ship. The reason the method has not been used before is that it requires measuring the gas concentration in the atmosphere very rapidly -- 10 times per second -- in addition to even faster measurements of the wind flow in three dimensions around the ship, and the precise location, acceleration and motion of the ship relative to the sea surface. Faster, smaller, accelerometers and inertial navigation units, similar to the chips which let smartphones know when you turn them sideways or upside down, as well as faster spectrometers for the methane measurement, and a detailed model of airflow around Oden, made this measurement possible.

"By understanding the airflow over the sea surface, and simultaneously measuring methane concentrations, we can determine how much methane is coming out of the ocean," explains researcher Brett Thornton at the Department of Geological Sciences, Stockholm University.

...

This new study shows that "hotspots" of methane emission from the sea can be up to 25 times higher than emissions from on-shore wetlands. These emissions are driven by bubbles coming from the seafloor and reaching the sea surface. This study directly observed very high peak emissions and, for the first time, was able to map their spatial extent.

"The peak emissions are indeed large but at the same time they are also extremely limited in area," says Brett Thornton.

Across the Laptev, East Siberian, and Chukchi seas the authors saw no evidence of widespread emissions at the magnitude of the "hotspots." In fact, their estimates for total methane emission from the eastern Arctic Ocean did not substantially increase even when they included these "hotspots" in the budget calculations.

"What this means is that -- at least at the time of our measurements -- the shallow eastern Arctic Ocean was not a huge source of methane to the atmosphere, and our understanding of Arctic sea emissions in the methane cycle is still reasonably correct.

https://www.sciencedaily.com/releases/2020/01/200130115433.htm


Shipborne eddy covariance observations of methane fluxes constrain Arctic sea emissions
https://advances.sciencemag.org/content/6/5/eaay7934

The Sverus data is from 2014.
I would like to see the same sort of measures taken again this year or sometime soon.
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vox_mundi

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Re: Arctic Methane Release
« Reply #1115 on: February 14, 2020, 05:08:09 PM »
NASA Flights Detect Millions of Arctic Methane Hotspots
https://www.jpl.nasa.gov/news/news.php?feature=7598

... In a new study, scientists with NASA's Arctic Boreal Vulnerability Experiment (ABoVE) used planes equipped with the Airborne Visible Infrared Imaging Spectrometer—Next Generation (AVIRIS—NG), a highly specialized instrument, to fly over some 20,000 square miles (30,000 square kilometers) of the Arctic landscape in the hope of detecting methane hotspots. The instrument did not disappoint.

"We consider hotspots to be areas showing an excess of 3,000 parts per million of methane between the airborne sensor and the ground," said lead author Clayton Elder of NASA's Jet Propulsion Laboratory in Pasadena, California. "And we detected 2 million of these hotspots over the land that we covered."

The paper, titled "Airborne Mapping Reveals Emergent Power Law of Arctic Methane Emissions," was published Feb. 10 in Geophysical Research Letters.

... Within the dataset, the team also discovered a pattern: On average, the methane hotspots were mostly concentrated within about 44 yards (40 meters) of standing bodies of water, like lakes and streams. After the 44-yard mark, the presence of hotspots gradually became sparser, and at about 330 yards (300 meters) from the water source, they dropped off almost completely.

The scientists working on this study don't have a complete answer as to why 44 yards is the "magic number" for the whole survey region yet, but additional studies they've conducted on the ground provide some insight.

"After two years of ground field studies that began in 2018 at an Alaskan lake site with a methane hotspot, we found abrupt thawing of the permafrost right underneath the hotspot," said Elder. "It's that additional contribution of permafrost carbon—carbon that's been frozen for thousands of years—that's essentially contributing food for the microbes to chew up and turn into methane as the permafrost continues to thaw."



Clayton D. Elder et al. Airborne Mapping Reveals Emergent Power Law of Arctic Methane Emissions, Geophysical Research Letters (2020)
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