The work of the Swedish and Russian team on the Yakov Smirnitsky has finally found its way into the mainstream media, with Steve Connor at the Independent in London reporting the final post at the ISSS-08 blog I’ve been linking to for the last month or two. It’s not good news – they’ve found dramatic evidence of “methane chimneys” – bubbles of methane emerging form the sea floor and reaching the surface (instead of dissolving), and recorded atmospheric concentrations 100 times the normal background level. Connor reports on an email exchange with the Swedish team:
“We had a hectic finishing of the sampling programme yesterday and this past night,” said Dr Gustafsson. “An extensive area of intense methane release was found. At earlier sites we had found elevated levels of dissolved methane. Yesterday, for the first time, we documented a field where the release was so intense that the methane did not have time to dissolve into the seawater but was rising as methane bubbles to the sea surface. These ‘methane chimneys’ were documented on echo sounder and with seismic [instruments].”
At some locations, methane concentrations reached 100 times background levels. These anomalies have been seen in the East Siberian Sea and the Laptev Sea, covering several tens of thousands of square kilometres, amounting to millions of tons of methane, said Dr Gustafsson. “This may be of the same magnitude as presently estimated from the global ocean,” he said. “Nobody knows how many more such areas exist on the extensive East Siberian continental shelves.
In his piece, Connor uses the “standard” global warming potential for methane of 20 times CO2 (actually 25 is the official IPCC number), and correctly notes the short atmospheric lifetime of the gas. However, over that short lifetime (around 12 years), CH4’s GWP is more like 70 times CO2. Current global methane level is about 1750 ppb (1.75 ppm), so using a GWP of 25 it has the same warming effect as 43.75 ppm CO2. On the shorter 10 year time scale, that’s more like 122 ppm CO2. But Semiletov and his team on the Yakov Smirnitsky have measured concentrations 100 times greater than “normal”, which implies a local warming effect equivalent to 12,200 ppm CO2.
Luckily, it’s getting dark up there, but methane release on that scale might slow down the winter cooling in the region of the chimneys. Methane seeps in lakes can keep holes open in winter ice, so if persistent holes start appearing in the satellite maps of sea ice over the Siberian seas, we’ll know there’s a big issue (the holes would have to be huge to be seen in the data). We urgently need more info on the extent of the problem. There’s a lot of methane under the Siberian seas – we can only hope it stays there.
The NZ Herald reprints the Independent story, and the Guardian puts its own spin on it (a note of caution). This is a story that needs wider coverage, more informed scientific debate, and great deal more study. I hope Connor’s piece doesn’t get dismissed as hype, or “alarmism”. You don’t need to be an alarmist to find this stuff alarming…
There’s a big diminishing increase though. Perhaps someone has done some analysis on the increased absorption?
Begs the question – is methane released in a less intense fashion simply absorbed by seawater, thus nullifying the warming potential of the gas? Does methane gas released by say, coal seams get absorbed by sea water too? Sounds similar to the seawater/CO2 absorption situation…
Sam – not sure about how the radiative forcing of methane is affected by concentration: I need to check AR4… However, the local high concentration will be effectively diluted by the rest of the atmosphere as soon as the wind blows..
Stephen – methane can dissolve in sea water, but will outgas at the surface to increase atmospheric concentration. Obviously, you need to saturate a lot of seawater first, so there’s a considerable buffering effect. But increased methane in solution has certainly been measured north of Siberia. For those bubbles to get to the surface through tens of meters of water, and for the streams to show up like “shoals of herring” on sonar suggests that a lot of methane is being released…
Stephen,
Gerald Dicken’s paper, ‘Hydrocarbon-driven warming’ in Nature Vol 429 (2004 pp 513-515) includes a simple diagram that explains some aspect of the chemistry – not quite the same as what you’re getting at but it’s worth having a look at. I’m not a chemist but I followed it .
http://www.nature.com/nature/journal/v429/n6991/full/429513a.html
If you can’t access the paper, let me know and I’ll forward a copy plus the paper by Svensen that he’s referring to, in the same issue.
Sonny
Thanks Sonny, yeah I do have access. Pretty simple diagram, but that’s what is so good about it. The Svensen one was a bit stats-y, but massive explosions are always interesting.
Off-topic-ish, but the current issue has an article on an ecosystem sequestration experiment Ecosystem CO2 uptake: Prolonged after-effects of an extremely warm year. :
No surprise, but it’s still left me reeling.
Thanks for your coverage of this issue Gareth.
Beyond the more obvious impact of methane in the atmosphere, what I find striking in regard to instances of sudden methane ‘burps’, (such as occurred during the Eocene, for eg) is their link to wholesale changes in oceanic chemistry, nutrient and oxygen exchange, and altered heat-transfer resulting in gross shifts in currents planet-wide.
So, methane, not a GHG, then.
Sonny
Sonny
Gareth, this was a major IPY project, and there’s a second observing expedition (Canadian IIRC) from whom we have heard nothing, so I would say it’s more a matter of waiting for the official results than worrying about the story getting buried. Also, Andy Revkin has this now and is probably much better situated in terms of getting information out of North American scientists, so perhaps we’ll see something more soon.
Ahem…what I meant to say in my above post was ‘methane, not just a GHG then’.
Sonny
Hi Gareth,
Are you sure that the figure of 100 times background concentrations relates to atmospheric concentrations? My reading of the brief report from the research team is that they could be tallng about concentrations of methane dissolved in seawater.
I’m inclined to think it’s atmospheric concentrations. Earlier work (Shakova’s paper at this year’s EGU conference – blogged here) found methane at 8 ppm – which is about 5x background. Over a steady stream of pure methane bubbles it could easily be much higher – but as others have suggested, we’ll have to wait until the data is published to be sure.
Atmospheric CH4 concentrations stopped rising in 1998.
http://commons.wikimedia.org/wiki/Image:Methane-global-average-2006.jpg
No-one knows why.
Catastrophe cancelled.
Wrong again, Steve. You don’t seem to be up with the news. And it’s old news (April) too.
This may be worth a look:
http://www.abc.net.au/catalyst/stories/2373958.htm
Handy Laurence. Am disappointed they didn’t go any further with this though:
Dr Etheridge: From 1978 onwards (the earliest measurements) there was a rapid increase in methane concentration.
Narration: And this was mainly because of an increase in agriculture and industry. But then something unexpected happened –
Dr Etheridge: Methane has stabilized in concentration ah beginning in about 1999. And it wasn’t too clear what that was…
Stephen I think if you read a bit further in the transcript you will find this
Dr Etheridge: In the last year and a half, methane is now increasing again in the atmosphere.
The online video explains it quite well, although I can’t get it to play past 6 min (bandwidth issue I think). There is also this, released today on ABC radio. http://www.csiro.au/news/EmissionsRising.html
Yeah Laurence I know it’s increasing again, I simply wanted to know why it stabilised…
Some theories I’ve encountered (can’t vouch for them with refs):
• better capture of gas at oil wells, less leakage from pipelines/shipping etc as gas prices increased
• slow down in expansion of rice growing areas as higher yielding strains are planted
… but I wouldn’t mind knowing more, either
Sorry Mate, can’t help you much there, although I suspect Gareth is on the right track. There are a least 2 major gas capture companies over here, into Coal Bed Methane. Queensland Gas Company Limited and Sydney Gas Limited have both been operating prior to 1998. I believe both are working with coal miners to bleed off methane before the seems are opened. As well as better rice varieties there has also been a steady decline in production for a number of years, due to drought conditions. http://www.iht.com/articles/2008/04/17/business/17warm.php
Better recycling and landfill management may also have had an effect. Any and all of these things may have had something to do with the stabilisation, but of course it is all guesswork on my part.
You can contact David Etheridge here http://www.dar.csiro.au/profile/etheridge.html
He may be able to give you further information. And for a bit more reading http://www.cmar.csiro.au/research/tla.html
Ta. Still a little hard to imagine all the effects cited here as significantly affecting methane emissions on a *global* scale, but perhaps I will do some digging…
Here you go Stephen, a couple of links to get you going. http://www.csiro.au/multimedia/MethaneMystery.html
http://www.sciencedaily.com/releases/2006/09/060927201651.htm
Incidentally, coal bed methane capture is not unique to Australia, it’s just that outside the United States, Australia has the most commercially advanced coal mine methane (CMM) and coal bed methane (CBM) industry.
http://waterquality.montana.edu/docs/methane/cbmfaq.shtml
Off topic- Ken Ring so how did not predict the snow dump in the bottom of the South Island. What a surprise!
Stephen,
http://www.cosis.net/abstracts/EGU06/05277/EGU06-J-05277.pdf
“Anthropogenic methane emissions and recent trends in atmospheric methane concentrations.” E Matthews 2006.
Hope that helps.
Thanks chaps…always good to have on record somewhere too.
Over at Stoat, I asked:
Anyone know why the 13C content of CH4 rose in 2007/8?
My post is here.
I got no answer there. Anyone here got any ideas?
For what it’s worth I think it rules out the current methane increase being due to clathrates. However that doesn’t mean at some stage that the isotope fraction change won’t go the other way (as clathrates outgas).
CobblyWorlds
I’d very much like to see 13C measurements from the subsea (if they took them), underwater, and atmospheric samples taken by the Yakov Smirnitsky team. Someone else must be measuring the 13C and 12C from clathrates outgas. I’ll see if I can track down some research. I’m quite intrigued.
Sonny
Cobblyworlds,
This might supply a clue: http://www.iarc.uaf.edu/highlights/2006/arctic_ocean_methane/index.php
The key phrase being, “Upon thawing they (methane producing bacteria) restore activity and begin to produce a lot of modern methane from ancient organic matter preserved within the permafrost.
Sonny
I was just (finally) filing away some papers on my desk when I came across: Origin of 13C-enriched methane in the crater lake Towada,Japan (http://www.terrapub.co.jp/journals/GJ/frame/33.html (no firewall).)
I admit, I hadn’t made the mental link earlier because I tend to think of Arctic and volcanoes as unrelated…except of course for the paper that Stephen cited in post 5 above: ‘The Svensen one was a bit stats-y, but massive explosions are always interesting.’
So, you just had to mention a high 13C in Arctic methane, didn’t you?
Thanks, CobblyWorlds. I can sleep *so* much better now (finding a plausible scientific reason for a big bang is an occupational hazard for me, I’m afraid 😉 )
Sonny
Sonny,
Were there not such interest in the Arctic and in the clathrates, what the ISSS08 team are now discovering would be the unobserved precursor to what would be found by those investigating the reason for the negative excursion in 13C that will come.
I can’t access the Nature paper by Dickens that you refer to. But thanks for the links above, Modern bacterial activity looks interesting. Also thanks for the japanese publication link, if I continue studying this issue I’ll be browsing there.
“Got a little feelin’ times is gonna be bad.
Those good ol’ days have all a been had.
If now is where tomorrow’s come to rehearse.
Today the future just got much worse.”
Robert Newman, “History of Oil”
Cobblyworlds,
Email me: sonnyw [at] optusnet.com.au and I’ll forward the Nature papers if you like. (that email address will only be valid for a couple of weeks).
Sonny
Sonny,
I’m having a holiday, from both work and my studies. But thanks for the offer – email on way.
If I continue I’ll look into your suggestion and contemporary biological activity. It’s interesting that this has increased notably for 2007/2008. I can’t figure out quite why – I had been pondering land warming/ocean warming or more fragmented ice. But right now I’m re-reading a load of Brian Aldiss.