Arctic collapse dramatically increases global warming?

ccgg.BRW.ch4.1.none.discrete.all Wosis then? Is it the sea ice? Ah, no. Someone else wants in on the limelight: “Parts of Arctic Siberia are releasing ten times more carbon into the atmosphere than previously thought, a University of Manchester scientist and an international team of researchers have found.”

Its the usual stuff:

much more greenhouse gas is being released into the atmosphere than previously calculated, from and ancient an large carbon pool held in a permafrost along the 7,000 km desolate coast of northernmost Siberian Arctic – dramatically increasing global warming. As the temperature climbs carbon, stored in vast ice walls along this Arctic coast called Yedoma, covering about one million km2 (four times the area of the UK), is pouring into the Arctic Ocean in one of the world’s most remote and desolate regions. This region is experiencing twice the global average of climate warming. While satellite images reveal thousands of kilometers of milky-cloudy waters along the Arctic coast, suggesting a massive influx of material, the Yedoma has remained understudied largely due to the region’s inaccessibility. By studying the thaw-eroding slopes of a disappearing island, the team found that the tens-of-thousands year old coastal Yedoma carbon is rapidly converted to CO2 and methane, even before being washed into the sea

and so on. It is honest enough to say quietly that the present rate of carbon release from the NE Siberian coast is not substantially affecting the CO2 levels in the global atmosphere yet – but then how can you possibly reconcile that with the headline? Or indeed the following text the scale of the release of both CO2 and methane into the atmosphere will have a huge effect. This will have consequences for the temperatures all over the world. There are various nutters pushing the “methane emergency” line. And although that in itself doesn’t discredit more serious people, the serious people need to talk sense and not just grab headlines, if they want to be taken seriously.

None of which says anything about the quality of the science, which sits quietly paywalled by Nurture. Its quite likely a valuable, if minor, contribution to our knowledge of carbon fluxes in the Arctic. It just doesn’t deserve the headlines it is offering.

And speaking of, errm, overenthusiasm, don’t get me started on Wadhams The entire ice cover is now on the point of collapse… It is truly the case that it will be all gone by 2015. No, it won’t be.

More sea ice and more methane

Arctic Methane Emergency Group? refers. Via GP I find this discussion on a “geoengineering” newsgroup (gosh how quaint – people still use newsgroups? Maybe retro is back). AJL finds my article “damming” but Ken C finds it “a little distasteful”. But both are worried, quite rightly, about credibility if the AMEG’s wilder claims (and people) aren’t challenged.

Ken C points to September Arctic sea ice predicted to disappear near 2oC global warming above present (JGR, doi:10.1029/2011JD016709) which is interesting, because that is very non-catastrophic and very non-nearterm: 2 oC puts it at ~2070 or something, depending on your scenario.

A recalibration of an ensemble of global climate models using observations over 28 years provides a scenario independent relationship and yields about 2oC change in annual mean global surface temperature above present as the most likely global temperature threshold for September sea ice to disappear, but with substantial associated uncertainty.

chart

Which brings me on to Now, and Cryosphere Today has a nice interactive chart, which I’ve inlined above (see-also). This year – yellow – seems quite wobbly; from bumping along the bottom it is now well up in the middle of the pack. But that is midwinter; there is still all to play for in the year ahead.

ccgg.BRW.ch4.1.none.discrete.all Switching very briefly to methane (the AMEG people were a bit annoyed their nice discussion had got hijacked by sea ice), the pic here shows… nothing very exciting. And it is Barrow, not global, per special request of Eli. This provides some kind of constraint on the hugeosity of whatever methane release is occurring in the Arctic.

And so, in the end, back to the Dark Side, where Watts had some story about sea ice. I ignored the bit about the Skate – if you’re interested, Eli has the story on that, and the other half too. But the bit about IPCC ’90 using pre-1978 sea ice was more interesting. Its true, they did (though it was a surprise to me). Presumably because back in 1990 the SSMI/R record was rather short, and it wasn’t obviously silly to use other stuff (for the full story, and exactly what other stuff, read RMG who knows). Anyway, I guessed wrong: it wasn’t ESMR (couldn’t have been, as RMG points out, because there would have been gaps). But what is fun, if you’re a detatched spectator, is how the Watties once again jump onto the good old conspiracy theories of how things were pure then but the global conspiracy has subsequently conspired to wipe out any memory of our giant reptilian overlords whatever. This is definitely a case where you don’t need fancy explanations for their errors. There is a constant stream of junk, no time to think or evaluate, and no need anyway – its all denialotainment, nothing real, and like the headline in the Daily Mail will be conveniently forgotten very soon.

Oh, and don’t mention Scafetta.

Refs

* Anthony Watts Misleading His Readers About Surface Temperature Record – it might be convenient to put this where I might find it again
* How reversible is sea ice loss? J. K. Ridley, J. A. Lowe, and H. T. Hewitt

Arctic Methane Emergency Group?

From Climate ‘tech fixes’ urged for Arctic methane I find ameg.me who say:

AMEG POSITION
DECLARATION OF EMERGENCY

We declare there now exists an extremely high international security risk* from abrupt and runaway global warming being triggered by the end-summer collapse of Arctic sea ice towards a fraction of the current record and release of huge quantities of methane gas from the seabed. Such global warming would lead at first to worldwide crop failures but ultimately and inexorably to the collapse of civilization as we know it. This colossal threat demands an immediate emergency scale response to cool the Arctic and save the sea ice. The latest available data indicates that a sea ice collapse is more than likely by 2015 and even possible this summer (2012). Thus some measures to counter the threat have to be ready within a few months.

So who are these bozos? (Note: I’ve been fairly dismissive about methane before). Aunty says “Scientists told UK MPs this week… At a meeting in Westminster organised by the Arctic Methane Emergency Group (Ameg), Prof Salter told MPs that…” so I think the first thing to realise is that there is less to this than meets the eye (Update: Geoengineering Politics has a report on the meeting that all this recent stuff has spun out of; I’ve also found (thanks cr) the written evidence to the committee, see the Refs). If you follow their “about” link you come to:

ABOUT AMEG
In the preparation of the 2010 workshop report and AGU conference poster presentation, scientific and/or engineering advice was sought and obtained from the following people

and there follows a list of distinguished-looking folk, whose only misfortune was to have talked to these people. Lower, we come to

a position statement on the Arctic methane emergency, proposed by the chairman, John Nissen, was agreed by the following:

Graham Ennis
Doly Garcia
Jon Hughes
Veli Albert Kallio
Graham Knight
Dr. Brian Orr
Prof. Stephen Salter
Prof. Peter Wadhams

Salter will be familiar to Old Folk as the inventor of the Duck, a doubtless noble project but which has, as far as I know, been perennially unused. Wadhams is a climate scientist – well, he is a sea ice person. The rest I don’t know. Wadhams has some credibility. Unfortunately, we don’t know what the position statement they agree was. They don’t directly link to it. It is possible that the text I’ve quoted is part of it, but its impossible to know.

Wadhams clearly believes something, see Rebuttal: Imminent collapse of Arctic sea ice drives danger of accelerated methane thaw (thanks B for reminding me). I see that page relies heavily on the Piomas graphs, whose extrapolation I’ve disagreed with before and do now. But onto what W says there: Archer clearly acknowledges the vulnerability of methane hydrates to thawing in response to rising Arctic temperatures. Given that ice loss is accelerating, which in turn will only accelerate that temperature rise through the albedo effect, one has to wonder why he does not perceive an imminent and urgent crisis, which certainly suggests that W does indeed believe in “an imminent and urgent crisis”. I think that is well over the top; I don’t think anything he says there supports it, nor do the links.

I’ve worked with Wadhams a little bit, in the past. Wadhams knows about sea ice, indeed as far as I know its his main specialism. But perhaps in a local-processes sense. He was involvedin garnering thickness data from UK submarine cruises. What I’m trying to say is that I wouldn’t really trust him to have a great deal of feel for the connection between sea ice and global-scale methane; I’d expect him to care for the Arctic, but quite possibly to over-emphasise local detail.

And apart from Wadhams I can’t see this group has any credibility.

Update: bottom-trawling, I ran across a comment at JEB (thanks VB) talking about “invaded by out-and-out nutters such as the UFOlogist and Arctic methane expert Graham Ennes (AKA ‘Omega Institute’)”. Well yes, GE (though with an “i”) is on that list. And yes, if you search for his name you’ll find some weird stuff. Wadhams ought to remember that if you lie down with dogs, you get up with fleas.

Update: The comment from Axel Schweiger is worth reading.

Update: in fact several other comments are also worth reading; take a look. I think I’m going to give my viewpoint (instead of just being ratty about other peoples). I’ve said this before but its quicker to write it down again than find it. The starting point is the measurements of atmospheric methane. These are nothing much to worry about. Indee they are below the old IPCC scenarios. If there was sudden truely massive venting from the Arctic, we’d be seeing it in those measurements. That leaves the harder problem of whether the Arctic warming (and in particular the recent decline in sea ice) is likely to lead to sufficient warming under the sea bed to release enough methane from clathrates that anyone would care. So far, the evidence warrants monitoring and study, not panic and geoengineering.

Refs

* Mid March Miscellanea from CR.
* I’m sure they’ll be delighted to know that this post is now the top google hit for “Arctic Methane Emergency Group”.
* https://sites.google.com/site/arctischepinguin/home/piomas may be the source for the PIOMAS graph the Beeb uses.
* Arctic Methane, Emergencies, and Alarmism
* Possible role of wetlands, permafrost, and methane hydrates in the methane cycle under future climate change: A review – REVIEWS OF GEOPHYSICS, VOL. 48, RG4005, 33 PP., 2010
doi:10.1029/2010RG000326 (thanks Bishop; I’ve inlined their fig 7).
* Evironmental Audit Committee – Written Evidence
* Environmental Audit Committee – Minutes of Evidence
* Neven discusses “the graph”
* [2014] How much methane came out of that hole in Siberia?
* [2014] Climate change and the methane crisis: Q & A with Harold Hensel – Zombie nutters from beyond the grave

Lack of methane growth explained?

I’ve said before (and correctly sourced the original observation to JA) that atmospheric methane is way below its IPCC scenarios (which of course leads to a lower forcing). There is a recent thing in Nature that may explain this:

Atmospheric methane (CH4) increased through much of the twentieth century, but this trend gradually weakened until a stable state was temporarily reached around the turn of the millennium1, 2, after which levels increased once more3. The reasons for the slowdown are incompletely understood, with past work identifying changes in fossil fuel, wetland and agricultural sources and hydroxyl (OH) sinks as important causal factors1, 4, 5, 6, 7, 8. Here we show that the late-twentieth-century changes in the CH4 growth rates are best explained by reduced microbial sources in the Northern Hemisphere. Our results, based on synchronous time series of atmospheric CH4 mixing and 13C/12C ratios and a two-box atmospheric model, indicate that the evolution of the mixing ratio requires no significant change in Southern Hemisphere sources between 1984 and 2005. Observed changes in the interhemispheric difference of 13C effectively exclude reduced fossil fuel emissions as the primary cause of the slowdown. The 13C observations are consistent with long-term reductions in agricultural emissions or another microbial source within the Northern Hemisphere. Approximately half (51 ± 18%) of the decrease in Northern Hemisphere CH4 emissions can be explained by reduced emissions from rice agriculture in Asia over the past three decades associated with increases in fertilizer application9 and reductions in water use10, 11.

(disclaimer: that is all I’ve read, not the actual text). But then again, perhaps you prefer a different answer, again from Nature:

Methane and ethane are the most abundant hydrocarbons in the atmosphere and they affect both atmospheric chemistry and climate. Both gases are emitted from fossil fuels and biomass burning, whereas methane (CH4) alone has large sources from wetlands, agriculture, landfills and waste water. Here we use measurements in firn (perennial snowpack) air from Greenland and Antarctica to reconstruct the atmospheric variability of ethane (C2H6) during the twentieth century. Ethane levels rose from early in the century until the 1980s, when the trend reversed, with a period of decline over the next 20 years. We find that this variability was primarily driven by changes in ethane emissions from fossil fuels; these emissions peaked in the 1960s and 1970s at 14-16 teragrams per year (1 Tg = 1012 g) and dropped to 8-10 Tg yr−1 by the turn of the century. The reduction in fossil-fuel sources is probably related to changes in light hydrocarbon emissions associated with petroleum production and use. The ethane-based fossil-fuel emission history is strikingly different from bottom-up estimates of methane emissions from fossil-fuel use1, 2, and implies that the fossil-fuel source of methane started to decline in the 1980s and probably caused the late twentieth century slow-down in the growth rate of atmospheric methane3, 4.

This science stuff is confusing, isn’t it? Good evidence says its due to changes in Agricultural emissions; but other good evidence says it is fossil fuel changes. Oh well, I suppose they will fight it out and we’ll know in a year or two.

[Update: this post made it to the main page. That might draw in a few folk from outside my usual in-crowd, so perhaps I’ll amplify that last paragraph a bit: as Eli says in the comments, likely the decrease is due to a variety of factors. My best guess would be that the two “competing” analyses here reflect people tending to see results in the mirror of their own tools.]

Another interesting one is C4 grasses prosper as carbon dioxide eliminates desiccation in warmed semi-arid grassland on the eternal problem of will CO2 fertilisation help, or will it get wiped out by encouraging the wrong sort of grass?

Oh yes, and there is another contribution to the Antarctic warming question: We use measured firn temperatures down to depths of 80 to 90 m at four locations in the interior of Dronning Maud Land, East Antarctica to derive surface temperature histories spanning the past few decades using two different inverse methods. We find that the mean surface temperatures near the ice divide (the highest-elevation ridge of East Antarctic Ice Sheet) have increased approximately 1 to 1.5 K within the past ∼50 years, although the onset and rate of this warming vary by site. Histories at two locations, NUS07-5 (78.65°S, 35.64°E) and NUS07-7 (82.07°S, 54.89°E), suggest that the majority of this warming took place in the past one or two decades. Slight cooling to no change was indicated at one location, NUS08-5 (82.63°S, 17.87°E), off the divide near the Recovery Lakes region. In the most recent decade, inversion results indicate both cooler and warmer periods at different sites due to high interannual variability and relatively high resolution of the inverted surface temperature histories. The overall results of our analysis fit a pattern of recent climate trends emerging from several sources of the Antarctic temperature reconstructions: there is a contrast in surface temperature trends possibly related to altitude in this part of East Antarctica.

Good grief, the world is full of new science all of a sudden:

The ongoing increase in extremely warm temperature events across large areas of the globe is generally thought to be a signature of a more extreme climate. However, it is still unclear whether global warming is accompanied by changes in statistical properties beyond the mean, such as an increasing temperature variability. Here we shed light on this issue by uncovering the way probabilities of extremes are being influenced by temperature evolution. Focusing on Europe, we show how the behavior of warm and cold extremes can be determined to a high accuracy by statistically modeling daily temperatures and their changes. Detailed comparison with observations over the past decades puts forward the dominant role of the mean in explaining exceptionally hot events, and rules out contributions from potential changes in second and higher moments.

(Evolution of extreme temperatures in a warming climate, C. Simolo et al.. Translation: no, things are not getting more extreme, it is just that the mean is increasing. Roger will be happy).

Refs

* Reduced methane growth rate explained by decreased Northern Hemisphere microbial sources Fuu Ming Kai, Stanley C. Tyler, James T. Randerson & Donald R. Blake, Nature 476, 194-197 (11 August 2011) doi:10.1038/nature10259
* Recent decreases in fossil-fuel emissions of ethane and methane derived from firn air Murat Aydin, Kristal R. Verhulst, Eric S. Saltzman, Mark O. Battle, Stephen A. Montzka, Donald R. Blake, Qi Tang & Michael J. Prather, Nature 476, 198-201 (11 August 2011) doi:10.1038/nature10352