Bubble plumes off Washington, Oregon suggest warmer ocean may be releasing frozen methane

October 14, 2015 by Hannah Hickey
Sonar image of bubbles rising from the seafloor off the Washington coast. The base of the column is 1/3 of a mile (515 meters) deep and the top of the plume is at 1/10 of a mile (180 meters) depth. Credit: Brendan Philip/University of Washington

Warming ocean temperatures a third of a mile below the surface, in a dark ocean in areas with little marine life, might attract scant attention. But this is precisely the depth where frozen pockets of methane 'ice' transition from a dormant solid to a powerful greenhouse gas.

New University of Washington research suggests that subsurface warming could be causing more gas to bubble up off the Washington and Oregon coast.

The study, to appear in the journal Geochemistry, Geophysics, Geosystems, shows that of 168 bubble plumes observed within the past decade, a disproportionate number were seen at a critical depth for the stability of .

"We see an unusually high number of bubble plumes at the depth where methane hydrate would decompose if seawater has warmed," said lead author H. Paul Johnson, a UW professor of oceanography. "So it is not likely to be just emitted from the sediments; this appears to be coming from the decomposition of methane that has been frozen for thousands of years."

Methane has contributed to sudden swings in Earth's climate in the past. It is unknown what role it might contribute to contemporary climate change, although recent studies have reported warming-related methane emissions in Arctic permafrost and off the Atlantic coast.

Of the 168 methane plumes in the new study, some 14 were located at the transition depth - more plumes per unit area than on surrounding parts of the Washington and Oregon seafloor.

If methane bubbles rise all the way to the surface, they enter the atmosphere and act as a powerful greenhouse gas. But most of the deep-sea methane seems to get consumed during the journey up. Marine microbes convert the methane into carbon dioxide, producing lower-oxygen, more-acidic conditions in the deeper offshore water, which eventually wells up along the coast and surges into coastal waterways.

Map showing locations of the 168 bubble plumes used in the study. Credit: University of Washington

"Current environmental changes in Washington and Oregon are already impacting local biology and fisheries, and these changes would be amplified by the further release of methane," Johnson said.

Another potential consequence, he said, is the destabilization of seafloor slopes where acts as the glue that holds the steep sediment slopes in place.

Methane deposits are abundant on the continental margin of the Pacific Northwest coast. A 2014 study from the UW documented that the ocean in the region is warming at a depth of 500 meters (0.3 miles), by water that formed decades ago in a global warming hotspot off Siberia and then traveled with ocean currents east across the Pacific Ocean. That previous paper calculated that warming at this depth would theoretically destabilize methane deposits on the Cascadia subduction zone, which runs from northern California to Vancouver Island.

At the cold temperatures and high pressures present on the continental margin, methane gas in seafloor sediments forms a crystal lattice structure with water. The resulting icelike solid, called methane hydrate, is unstable and sensitive to changes in temperature. When the ocean warms, the hydrate crystals dissociate and methane gas leaks into the sediment. Some of that gas escapes from the sediment pores as a gas.

The 2014 study calculated that with present ocean warming, such hydrate decomposition could release roughly 0.1 million metric tons of methane per year into the sediments off the Washington coast, about the same amount of methane from the 2010 Deepwater Horizon blowout.

The new study looks for evidence of bubble plumes off the coast, including observations by UW research cruises, earlier scientific studies and local fishermen's reports. The authors included bubble plumes that rose at least 150 meters (490 feet) tall that clearly originate from the seafloor. The dataset included 45 plumes originally detected by fishing boats, whose modern sonars can detect the bubbles while looking for schools of fish, with their observations later confirmed during UW research cruises.

Results show that is slowly released at almost all depths along the Washington and Oregon coastal margin. But the plumes are significantly more common at the critical depth of 500 meters, where hydrate would decompose due to seawater warming.

"What we're seeing is possible confirmation of what we predicted from the water temperatures: Methane hydrate appears to be decomposing and releasing a lot of gas," Johnson said. "If you look systematically, the location on the margin where you're getting the largest number of methane plumes per square meter, it is right at that critical depth of 500 meters."

Still unknown, however, is whether these plumes are really from the dissociation of frozen methane deposits.

"The results are consistent with the hypothesis that modern bottom-water warming is causing the limit of methane hydrate stability to move downslope, but it's not proof that the hydrate is dissociating," said co-author Evan Solomon, a UW associate professor of oceanography.

Solomon is now analyzing the chemical composition of samples from bubble plumes emitted by sediments along the Washington coast at about 500 meters deep. Results will confirm whether the gas originates from methane hydrates rather than from some other source, such as the passive migration of methane from deeper reservoirs to the seafloor, which causes most of the other bubble plumes on the continental margin.

Explore further: Energy Department seeks methane hydrate proposals

More information: Geochemistry, Geophysics, Geosystems, onlinelibrary.wiley.com/doi/10.1002/2015GC005955/abstract

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43 comments

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gkam
3.1 / 5 (21) Oct 14, 2015
This is very bad news. It is a reaction with positive feedback, and can only produce more methane and more heat to release even more methane.
Returners
1.8 / 5 (15) Oct 14, 2015
Poor, poor gkam.

You know this has been happening forever, right?

It's called Confirmation Bias.

They didn't have fish finders 100 years ago, so they wouldn't have seen all these Methane plumes which have been there all along.

However, these bozo scientists can't comprehend that, so they think something new is happening.
gkam
2.9 / 5 (19) Oct 14, 2015
No, they have been watching for them. We understand the release of methane hydrates and clathrates can change the climate through the greenhouse effect.

And I did the test engineering to put out National's version of the LM1812 in 1974, over 40 years ago. We have had the technology long enough to have found it before.
my2cts
3.9 / 5 (22) Oct 14, 2015
Poor, poor gkam.

You know this has been happening forever, right?

It's called Confirmation Bias.

They didn't have fish finders 100 years ago, so they wouldn't have seen all these Methane plumes which have been there all along.

However, these bozo scientists can't comprehend that, so they think something new is happening.

You can not back that up.
You can not back up anything you have been spamming this blog with.
You have completely lost it.
jeffensley
2.8 / 5 (9) Oct 14, 2015
We do have a tendency to assume that things we observe for the first time are "new". You can't back up that this has been happening all along nor can you backup that this has just started. The only thing that can be accurately stated is that it is happening presently.
leetennant
3.6 / 5 (14) Oct 14, 2015
And there it is. We are fucked.
RealityCheck
3.3 / 5 (14) Oct 14, 2015
Hi all. Again, just in today to keep in touch/read-through again.

PS: Hi jeffensley. :) While I applaud your evenhandedness, I must point out you missed some obvious/well-known correlations which make the 'newness' of the latest observations real/likely, and not just an 'artifact' of observational timing/encountering. Consider: Perma-frost reservoirs in many regions (which have been warming due to climate change) show similar increases of 'new' outgassings by Methane/COs previously trapped in clathrates/hydrates due to previously cooler conditions. The same was also predicted to happen to undersea/undersediment when the warming due to climate change reached said previously cooler methane/CO2 'reservoirs'. These 'new' escapes from previously 'entombed' Methane/CO2 in cooler hydrate/clathrate conditions is now being triggered as predicted. So it isn't 'rocket science' to expect that at least SOME of these 'plumes' are beyond 'usual 'background' sources. Good luck to us all. :)
Jeffhans1
4.3 / 5 (3) Oct 14, 2015
Since the sea level has gone up 125 meters in the last 20,000 years, doesn't that mean that all of these formations that are vulnerable are at least that recent? How long does it take the current amounts to accumulate and how often are they released again? The long term climate fluctuates enough that these must decompose regularly during the warmer periods.
jeffensley
1.8 / 5 (10) Oct 14, 2015
Since the sea level has gone up 125 meters in the last 20,000 years, doesn't that mean that all of these formations that are vulnerable are at least that recent? How long does it take the current amounts to accumulate and how often are they released again? The long term climate fluctuates enough that these must decompose regularly during the warmer periods.


I'd tend to agree. All these releases from more recently immobile CO2/methane sources were mobile in the past. Methane has a short lifespan in the atmosphere. If we haven't been seeing significant heating from it already, it's not likely going to have the effect that alarmists fear it will.
Returners
2 / 5 (8) Oct 15, 2015
Poor, poor gkam.

You know this has been happening forever, right?

It's called Confirmation Bias.

They didn't have fish finders 100 years ago, so they wouldn't have seen all these Methane plumes which have been there all along.

However, these bozo scientists can't comprehend that, so they think something new is happening.

You can not back that up.
You can not back up anything you have been spamming this blog with.
You have completely lost it.


Well, I proved the definition of energy is flawed, and I proved the defintion of "heat" and "temperature" are flawed too.

Not sure how to fix it though, it works well enough for most day to day interactions, but when you start talking about astronomy/cosmology or perhaps the very small, quantum scale, I don't see how it can be said to be true either way.

You guys are worrying about all this crap too much. It's not the end of the world, nor the end of humanity even if things go bad...
Uncle Ira
4.2 / 5 (10) Oct 15, 2015
Hi all. Again, just in today to keep in touch/read-through again.


@ Really-Skippy. How you are again too Cher? I am doing just fine and dandy, thanks for asking.

I guess you are busy with the big climatic conference, eh? Since you make just the one postum I mean. Be sure to give us a few updates if you get the chance to let us know how your Really-Cavalry thing is going over with the scientists and humans at the meeting.

See you later and try not to breath too much of that really dirty smog over there in China. If that is the meeting you are at I mean. Is that the one you are at? Or some another one?
kafantaris
2.6 / 5 (5) Oct 15, 2015
The release of frozen methane is the danger we have feared and It is here already -- on the West Coast. And it will further accelerate warming.
Time for debate is definitely over and the need for fast action is here. Now we may also have to worry about earthquakes since frozen methane held the seafloor together: "frozen methane acts as the glue that holds the steep sediment slopes in place."
bluehigh
5 / 5 (4) Oct 15, 2015
The 'West Coast' of where?

katesisco
2.7 / 5 (7) Oct 15, 2015
Well, doesnt that mean that there is heat underneath? Like from the MOHO? And what would be causing the heat from the MOHO? Possibly the neutrino morph?
The sun, Sol, is producing larger coronal holes. What happens when the 'coronal hole' covers the entire surface of Sol? Would that be called a flare if we could see it?
weathervane
2.3 / 5 (3) Oct 15, 2015
So large bubble columns coming of hydrate are more than likely from free biogenic gas under hydrate migrating along faults rather than the top layer of hydrate healing and disassociating. The fact that the fishermen are there is a dead giveaway that this this is a long term system, the fisheries are probably driven of the chemsynthetic community which forms the basis of the food chain. This is no different from say east coast of NZ. Remember that when you eat your next deep water fish
chapprg1
2.3 / 5 (3) Oct 15, 2015
Even in mixed layer warming areas , think el Nino, the temperature at 500 meters shows very little temperature increase on order of 0.0x C. Do we really believe this is triggering methane release. If we are really that close, maybe there is reason for concern. The statement that the methane bubbles are converting to CO2 before reaching the surface shows little concern even if there is to be an increase.
patriceay
1 / 5 (1) Oct 15, 2015
Methane hydrates formed massively after the Eemian, 115, 000 years ago. The Eemian was the last really warm interglacial, caused by Earth orbital parameters (warm summers melted the ice).
CO2 reached 400ppm, and there was a rapid sea level, reaching 6 meters above present sea level.

After the end of the last great glaciation, warm waters transformed methane-water ice into plain methane catastrophically fast: craters in the sea bottom, and tsunamis in excess of fifty feet happened (some say 30 meters on the Scottish coast and what is presently the bottom of the southern North Sea).

So far, the claim has been that massive releases of methane do not reach the ocean surface, so do not contribute to global warming. So far.

Observed: in an Alpine lake above timber line last summer the release of gases was massive, and the thousands of bubbles unnerving, and probably dangerous.
patriceay
1 / 5 (1) Oct 15, 2015
The release of methane hydrates is just part of the evidence of non-linear warming. Another is the (predicted) apparition of the cold blob from melting over the Atlantic. That is apparently starting to short-circuit and stall the Gulf Stream (hence quick sea level rise in the north-east of the USA). Google: "Patrice Ayme cold blob north Atlantic" for a recent synopsis.
mtc123
1.7 / 5 (6) Oct 15, 2015
"...warmer ocean may be releasing frozen methane"
Methane freezes at -296.5 F or 91K at 1atm.
Perhaps if carbonated beverages (beer, coke, etc.) were banned the warming would reverse.
Up for it?
my2cts
3.7 / 5 (12) Oct 16, 2015

Well, I proved the definition of energy is flawed, and I proved the defintion of "heat" and "temperature" are flawed too.

Not sure how to fix it though, ...

Self delusion, narcissism. Combine this with religious and racial bigotry and you get a dangerous mixture.
my2cts
3.5 / 5 (11) Oct 16, 2015
@mtc123
"...warmer ocean may be releasing frozen methane"
Methane freezes at -296.5 F or 91K at 1atm.
Perhaps if carbonated beverages (beer, coke, etc.) were banned the warming would reverse.
Up for it?

You are in need of some education. It's free.
"Methane clathrate (CH4·5.75H2O) or (4CH4·23H2O), also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, or gas hydrate, is a solid clathrate compound (more specifically, a clathrate hydrate) in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice.
... significant deposits of methane clathrate have been found under sediments on the ocean floors of the Earth."
https://en.wikipe...lathrate
antigoracle
2.6 / 5 (10) Oct 16, 2015
Still unknown, however, is whether these plumes are really from the dissociation of frozen methane deposits.

Yeah... but let's blame GloBULL warming anyway...the Chicken Littles are hungry.
Benni
2.8 / 5 (13) Oct 16, 2015
The release of frozen methane is the danger we have feared and It is here already -- on the West Coast. And it will further accelerate warming.
Time for debate is definitely over and the need for fast action is here. Now we may also have to worry about earthquakes since frozen methane held the seafloor together: "frozen methane acts as the glue that holds the steep sediment slopes in place."


It's been here for (b)millions of years, we're only just now discovering it. Methane is what you get when LIFE is present. To get rid of methane, you need to extinguish all earthly life.
gkam
1.4 / 5 (10) Oct 16, 2015
Benni, go back to differential equations. You are not in your field here, and are projecting from your own prejudice.
my2cts
3 / 5 (10) Oct 16, 2015
@gkam
Don't encourage the troll on ODEs please ;-)
my2cts
3.5 / 5 (13) Oct 16, 2015
Still unknown, however, is whether these plumes are really from the dissociation of frozen methane deposits.

Yeah... but let's blame GloBULL warming anyway...the Chicken Littles are hungry.

Are you even old enough to post here?
retrosurf
3 / 5 (2) Oct 16, 2015
From the article:

>But most of the deep-sea methane seems to get consumed during the journey up.

This is good news based on recent, new knowledge. Scientists were surprised by the efficiency of bacteria at absorbing and metabolizing the truly large amounts of methane in the Gulf of Mexico from the Deepwater Horizon wellhead accident.

Of course, dumping that much "food" into a bacterial ecosystem could have dire consequences for the rest of the sealife that lives around there. We'll see. The west coast of North America is already having habitat problems from the warmer water that are impacting commercial fishing.

SuperThunder
1 / 5 (7) Oct 16, 2015
I always wanted to see an alien planet where no humans could live, I am so glad you can have those delivered to your own world now.
antigoracle
2.8 / 5 (9) Oct 16, 2015
Still unknown, however, is whether these plumes are really from the dissociation of frozen methane deposits.

Yeah... but let's blame GloBULL warming anyway...the Chicken Littles are hungry.

Are you even old enough to post here?

Funny, that's what yuh momma said.
TheGhostofOtto1923
4.1 / 5 (9) Oct 16, 2015
Benni, go back to differential equations. You are not in your field here
Well neither are you. Your degree is a lie.
and are projecting from your own prejudice.
And you are projecting the prejudicial proposition that because you WANT to be an expert, then you are.

Evidence proves otherwise.
And I did the test engineering to put out National's version of the LM1812 in 1974, over 40 years ago
Horseshit.
my2cts
3 / 5 (8) Oct 16, 2015
Still unknown, however, is whether these plumes are really from the dissociation of frozen methane deposits.

Yeah... but let's blame GloBULL warming anyway...the Chicken Littles are hungry.

Are you even old enough to post here?

Funny, that's what yuh momma said.

I thought so.
Benni
2.8 / 5 (13) Oct 16, 2015
Benni, go back to differential equations. You are not in your field here, and are projecting from your own prejudice.


geek, I don't need Differential Equations to figure out that the existence of methane below the ocean floors are not some kind of new phenomena. You simply need to learn to believe the evidence of ice core samples & the known history of the evolution of the oceans.......Hey, don't complain about that methane, go out & capture some of it in a propane tank & you'll have just one more free self-sufficient tools to add to you repertoire of energy diversification.
gkam
1.4 / 5 (10) Oct 17, 2015
It ain't an original thought, Benni. As usual, you only follow directions, like in differential equations. Real folk think and produce, integrate, and look for synergy. You run numbers. Computers do it better.
Chris Goldfinger
3.7 / 5 (6) Oct 18, 2015
I've been working on the structure, tectonics, methane hydrates and other aspects of the Cascadia margin since 1987. Methane plumes are very common all along the margin from California to Canada. We see them everywhere on all types of sonar systems. They occur at all water depths and are commonly linked to structural breaches of the numerous folds and mud diapirs, as well as active faults of which there are thousands. While a speedup of methane venting might possibly indicate a linkage to global warming, which is undoubtedly real, there is unfortunately no way to assess the overall rates of gas release over time to put that to the test. Linking a few random observations of gas plumes that have been going on since at least Miocene time, to global warming is not warranted, and undermines the good work being done by climate scientists. I'm surprised that something like this was published.
Dr. Chris Goldfinger, Oregon State University
antigoracle
3.5 / 5 (8) Oct 18, 2015
It ain't an original thought, Benni. As usual, you only follow directions, like in differential equations. Real folk think and produce, integrate, and look for synergy. You run numbers. Computers do it better.

Wow, real folk eh!
You should know, since you've been pretending to be one all your life, you Pathological Liar and hypocrite. When are you going to "integrate" and get solar panels like all your neighbours?
ab3a
3.9 / 5 (7) Oct 18, 2015
That methane-hydrates exist in the ocean depths is no surprise. However, it also not far from the subduction zone of the tectonic plates. Subduction would of course release some heat and that would be enough to release the methane.

Climate change is not entirely due to anthropogenic causes.
eachus
3 / 5 (2) Oct 18, 2015
I'm an engineer by training, retired now. All I could thing of reading about these methane plumes was how to capture them to sell as fuel. It wouldn't quite be renewable energy in the common idiom, but would add no new carbon (dioxide) to the environment.

What if there isn't enough methane in these plumes to be collected economically? Then there certainly isn't enough to affect global warming. BTW, I discovered in a paper I read a few days after the Deepwater Horizon blowout that there are several forms of methane clathrate. Most of them will decompose slowly, but there are critical pressures at which some changes are almost explosive in nature. One of them happens about the depth of the blowout preventer. I suspect that there was considerable clathrate in the BOP and when the bubbles in the pipe string reduced the pressure, there was no hope for the ship. (Would have been nice if the BOP had worked, but no one thought that an explosive event could knock the pipe off center.)
antigoracle
3 / 5 (8) Oct 18, 2015
Linking a few random observations of gas plumes that have been going on since at least Miocene time, to global warming is not warranted

Oh yes it is. You got to keep feeding the ignorant Chicken Littles.
Mike_Massen
1.9 / 5 (9) Oct 19, 2015
Benni Proves he cannot have any uni Engineering degrees with this immense ignorance
You simply need to learn to believe the evidence of ice core samples & the known history of the evolution of the oceans..
No Benni, you fail dismally in so MANY ways, you can't hazard a guess what graduate Engineers study !

Its NOT about "learning to believe" you utter dimwit !

Its the "balance of probabilities", ie ice core samples & sediments etc reflect regional conditions they can only (and) asymptotically reflect global conditions subject to convergent sampling criteria - basic (uni) Statistics, you should have learned this in your claimed degree in Nuclear Engineering, ie essential part of radio-active decay physics pre-requisites from mathematics - you liar/cheat, utter dimwit !

I've posted my creds, Benni post yours - where did you graduate & when ?

Or FFS why did you miss so very many lectures on so many inter-related pre-requisites yet STILL get a degree ?

Child !
Mike_Massen
1.9 / 5 (9) Oct 19, 2015
antigoracle also with naive attempt to marginalise claimed
Linking a few random observations of gas plumes that have been going on since at least Miocene time, to global warming is not warranted
Oh yes it is. You got to keep feeding the ignorant Chicken Littles
antigoracle, be genuine show stats re methane emissions & how they're factored into key Settled Physics of emissions ?

ie. For CO2 & methane
https://en.wikipe..._forcing
From
https://en.wikipe...transfer
And re vibrational states
http://cbc.arizon.../sim/gh/

antigoracle redneck idiot comment "Chicken Littles" isnt Science, be smart, deal with Physics first like a good boy, then assess the probabilities

Eg & NOT like child blurt by Benni of "Statistical Probabilities"

What does that really mean Benni - LOL in nice clear engineering language ?

Eg In context with your most recent usage in response to my earlier post ?

Shakes head - Engineer, LOL !
Mike_Massen
1.9 / 5 (9) Oct 19, 2015
eachus suggested
What if there isn't enough methane in these plumes to be collected economically? Then there certainly isn't enough to affect global warming
Perhaps but, in all of these issues quantification rules, of course based on Physics, this is something deniers can't seem to get their head around.

In terms of collection, it depends on how dispersed the resource is vs methodology of collection Eg in respect of fixed vs mobile. The volume for depth vs density distribution isnt yet clear to even start to make a commercial assessment so until then, the stuff continues to bubble up & according to the Physics of >100yrs & not refuted
https://en.wikipe..._forcing

based on
https://en.wikipe...transfer

&
http://cbc.arizon.../sim/gh/

in relation to humidity
https://en.wikipe...ometrics

A keen Physicist could work out the details but, only touched on in many engineering disciplines
jeffensley
3 / 5 (4) Oct 19, 2015
The release of frozen methane is the danger we have feared and It is here already -- on the West Coast. And it will further accelerate warming.
Time for debate is definitely over and the need for fast action is here.


There ya go... make the arbitrary weather phenomenon correlation that would get called out if a skeptic used it to say climate change wasn't real because of how cold the winters have been in their particular neck of the woods.
antigoracle
3 / 5 (6) Oct 19, 2015
Mutterin Mike is back with his blabbering and quoting his alma mater, Wikipedia.
Mutterin Mike my quote was from a scientist [Chris Goldfinger] studying this methane deposits for almost 30 years.

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