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Strong Methane Emissions On the Siberian Shelf
rrohbeck writes "The Independent reports brand-new results of high concentrations of methane — 100x normal — above the sea surface over the Siberian continental shelf. A large number of methane plumes have been discovered bubbling up from the sea floor. This is probably due to methane clathrate, buried under the sea floor before the last ice age, breaking up as higher water temperatures melt the permafrost that had contained it."
By a factor of 27 or so. That's why effluent processing plants will burn the stuff off (apart from the fact it gives them some power).
Engineering is the art of compromise.
Except that these are _recent_ findings. The outer core of the Earth has been molten for a long, long time. (At least, heck, 6000 years or so)
Works like this - first the permafrost/ice melts...this reduces/removes the main barrier that keeps the underlying water and sea floor at one relative temperature. Once that barrier is removed, the water and sea floor heat up, with the result being an increase in the release of otherwise captured methane.
It is actually a very simple, process...one that we could perhaps do without, of course, but hey - the times they are a change'n and Mother Nature is making the calls.
People have been expecting these Methane clouds:
http://afp.google.com/article/ALeqM5j3U0vEk53bVXHIcGUqqO64rvDAUg
"Melting of methane ice unleashed runaway global warming some 635 million years ago, according to a study released Wednesday that has implications for today's climate-change crisis.
Release of the potent greenhouse-gas, at first in small amounts and then in massive volumes, brought a sudden end to the planet's longest Ice Age, its authors believe.
During the "Snowball Earth" era, Earth froze over completely, with glaciers that crept down into the tropics and possibly even reached the equator."
The Hives: Hate to Say I told You So:
http://www.youtube.com/watch?v=tsm2hSKkH7E
Normally the relative greenhouse strength is corrected for a 100-year period (ie the shorter half life is already accounted for in the 27x number; I haven't checked the number, though).
It sounds like methane does have a feedback loop -- methane causes warming releases more methane. Sure, there's a limited amount down there, but it's a rather large amount. We'd really rather it stay put.
Not saying the CO2 isn't bad... but there's no shortage of other effects to go with it.
http://www.newscientist.com/article.ns?id=dn2088
"The release of massive clouds of methane from icy hydrates buried under shallow ocean floors is the leading suspect for the most devastating extinction in the fossil record, according to a new analysis.
Methane best matches the unusual carbon-isotope fingerprints found at the scene of the crime, says Robert Berner of Yale University in Connecticut, US, though it cannot explain atmospheric carbon dioxide levels at the time.
Berner says: "It's possible that you could have a combination" of effects causing the mass extinction that ended the Permian period, 250 million years ago. The event wiped out the vast majority of marine species and left Europe a near-desert."
Oh shi...
"we aren't currently getting the warmest temperatures of this century, so why has it just started now??"
It's called thermal inertia, however your question is still interesting.
I have followed the IPCC for many years and one of their biggest failures in accuracy has been what is sometimes called the "missing methane" problem. The 1997 IPPC report (and those that followed) predicted methane would keep rising but the follow up observations have (until now) shown the trend to be flat for the last 10yrs or so.
In otherwords the question is not why has it started rising again but rather why did it take an unexpected break for a decade?
BTW: I find it odd that the psuedo-skeptics have not lept on the missing methane issue as a way to discredit the IPCC, surely that would be more plausable than denying the North Pole is disintergrating, but that's politics for ya!
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
"Of course water is warmer... since the last glacial period... since the Little Ice Age... Oh, but recently oceans and atmosphere have been cooling."
How is this bullshit insightfull?
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
The mass extinction at the end of the Permian has been attributed to numerous causes. One of the prime theories also has to do with rapid release of methyl hydrates from ocean-floor clathrates.
The theory goes along the lines that oceanic overturning (exchange of bottom waters with surface waters) was limited in the Permian (even after the end of the Permo-Carboniferous glacial period), allowing accumulation of clathrates in oceanic sediments. However, overturning increased in the late Permian due to changes in oceanic circulation. This is conjectured to have caused massive releases of methane from methyl hydrates, with consequent large rapid swings in climate on land and in sea.
The evidence is not conclusive, but is strong. Most of it is derived from studies of marine fossils and isotope ratios. Discussion of the evidence and assessment of this and other theories for the extinction may be found, for example, in:
D.H. Erwin, The Great Paleozoic Crisis: Life and Death in the Permian, Columbia University Press, New York NY, 1993. ISBN:0715301306.
Of course, oceanic overturning is much stronger in the modern world, with deepwater formation especially strong in the North Atlantic and at the margins of Antarctica. This suggests the potential for clathrate release is probably rather less than it was in the late Permian, but not necessarily negligible. Another conjectured effect of global warming is slowing of oceanic overturning
The degree to which evidence supports these conjectures regarding ancient disruptions to climate is open to interpretation.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
Actually, if you look at this based on Global warming potential (GWP), Methane is 25 times worse than CO2 over the course of 100 years. So I think thats why he's saying that methane is still worse.
>>BTW: I find it odd that the psuedo-skeptics have not lept on the missing methane issue as a way to discredit the IPCC
I think the IPCC has done a good enough job discrediting themselves, with their predictions historically overstating global warming:
http://sciencepolicy.colorado.edu/prometheus/archives/climate_change/001317verification_of_1990.html
Where do you people come up with this sort of nonsense?
Here's the projected relationship between CO2 concentrations and temperature increase:
http://en.wikipedia.org/wiki/Image:IPCC_AR4_WGIII_GHG_concentration_stabilization_levels.png
Notice how it keeps going up?
That's assuming we don't hit some kind of positive feedback loop.
There's a warm and a cool interglacial. And a glacial.
We are still in the interglacial period.
And given that the end of the last glacial period is about the same as the average interglacial period, we are NOT (repeat NOT) just out of a glacial.
fuckwit.
For this kind of thing I suggest to read "The Swarm " novel from Frank Schatzing. :)
Methane Hydrate instability can be quite dangerous.....
> On the bright side, we might get to test this theory.
Wait. We might have the world's biggest fart on our hands, and your "bright side" is that we get to "test" (smell?) it? 0_o
Methane is odorless. Farts only contain up to about 10% methane. And before you ask: the methane produced by ruminant livestock usually is exhaled or "burped", not farted. Any more Urban Warming Myths?
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
What you're seeing on that graph is that 1998 was an unusually warm year. Also, 2008 was unusually cold. But if you look at the overall trend of the thirty years of the graph, you can see temperatures have been rising. For example, look how often the graph was above 0 before 1998, and compare to how often is was above 0 since 1998. It goes from spending about half the time below 0 to spending most of the time above 0. If you want to see the long-term trend, so a linear regression and you'll see it even more clearly.
What a fool believes, he sees, no wise man has the power to reason away.
Yes, we are in an "ice age", technically speaking. That's geologically defined to be when there are still large continental ice sheets in both hemispheres, such as Greenland and Antarctica. What we are in right now is an "interglacial" part of an ice age, a period when the ice sheets are not as large as they are in a full glacial period. See Wikipedia.
What matters isn't density, it's the total mass of water, dissolved salts, etc., that creates pressure. Adding water, even if it's distilled, adds mass and therefore pressure even if density decreases.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
I think what you're looking at is the infrared absorption spectrum. I quite agree that the principal frequencies at which carbon dioxide absorbs infrared are quite saturated - to a good approximation, all the infrared at those frequencies is absorbed.
Thing is, though, what happens then? Your molecule absorbs a photon and goes into an energetically excited state. There are two things it may now do. The molecule may collide with others, and the energy be spread as kinetic energy, warming the whole gas slightly. Or alternatively it may drop back to a ground state, emitting a photon at the same characteristic frequency. It's a 50-50 shot whether that photon goes down, back to Earth, keeping the place warm, or up, out to space, cooling the planet.
So, some percentage of the absorbed photons are re-emitted. Half of those which are, are going up. They'll probably be absorbed again by still more carbon dioxide higher up in the atmosphere. You end up with a statistical matter: how long does a typical infrared photon spend being scattered about in the atmosphere, before it ends up either as heat in bulk matter, or escaping into space? That is the problem. Add more carbon dioxide, and your average photon will have its first absorption sooner, trapping heat nearer the ground. And on average it will have more scatterings before any escape, increasing the likelihood of it becoming absorbed entirely into warm air or ground.
Real Daleks don't climb stairs - they level the building.
That you use the word "bleating" does not make them wrong. The Tragedy of the Commons is very real, and current economic systems are built around abuse of critical global commons--the atmosphere, topsoil, the sea, surface water, ... Any system that does not protect global commons will, quite literally, lead to the destruction of the world. You're seeing it now. Global warming is merely the fashionable cause du jour; very real, but there are others just as deadly.
"The biggest problem with communication is the illusion that it has taken place."
No, 4 C for 2xCO2 is a figure that includes positive feedbacks. Actually, 3 C is the IPCC's best estimate, although they say it is most likely 1.5-4.5 C. Without any positive feedbacks, it's more like 1.1 C (see Schlesinger and Andronova's 2002 article "Climate sensitivity" in EGEC). Of course, there are plenty of positive feedbacks which exist, and those lead to the IPCC's estimate. However, there are some positive feedbacks that people worry about which the IPCC didn't include in their assessment, because they are difficult to quantify, including some potential carbon cycle responses and Greenland ice sheet dynamics.
Then why do I keep getting asked to completely change my lifestyle and to spend vast sums of money to buy more expensive "carbon neutral" products?
Oh yeah? Who is asking you to spend "vast sums of money", and exactly how vast are we talking here? That's quite at odds with the fairly modest carbon taxes recommended by mainstream economists or the IPCC, on the order of $30/ton C.
As for changing your lifestyle, we're talking simple energy efficiency measures, not living in a mud hut eating bark and leaves.
This report has been called into question not just by crackpots but by reputable climatologists from many countries and backgrounds.
Fine, name one main IPCC conclusion which is is significantly at odds with the majority of the scientific literature.
On the "overstating" side, the Wikipedia article you cite doesn't have anything even remotely specific, just generic accusations of "distortion". On the "overstating" side, there are positive feedbacks which the IPCC neglected, but it stated it was intentionally doing so because it couldn't yet quantify those risks.
These is just the first one I could come up with and I didn't even look hard.
Collapse of the meridional overturning circulation is probably the aspect of climate with which I'm most familiar, actually. It's rather fanciful to describe it as a "Little Ice Age", since it's mostly limited to the North Atlantic region, and continental European temperatures are predicted to increase overall under the large amounts of warming necessary to trigger another collapse (see, e.g., the 2005 GRL paper by Gregory et al.). (That is, there is cooling due to the collapse, but it's offset by global warming itself.) The real temperature drops occur over the ocean, not land, although there could be some cooling over Greenland and Scandanavia. And the real risks associated with a modern MOC collapse are not an "ice age", but a shift in the zonal precipitation bands changing how much rainfall countries get. The secondary risk is due to different countries warming at different rates, making an overall adaptation strategy difficult. This is discussed in the National Academies report that your link cites.
And I'll again point out to you the assumptions and data involved in the IPCC report have been called into serious question by noted climatologists.
Please, point out the "noted climatologists" who question the basic premises of AGW.
The IPCC also completely ignores the fact that their own models used to predict this coming catastrophe cannot account for past weather trends,
Climate models do not and cannot predict weather. They do account for past climate trends, most notably the 20th century global warming.
nor can it account for the current cooling trend we are now experiencing.
We are not experiencing a cooling trend under any meaningful definition of the word "trend". (Averaging over a few years does not constitute a trend.) At best you can say that temperatures have been fairly flat for about a decade. However, given the size of the interannual variability in temperature, you can't statistically say whether that's an actual trend or just weather noise. Depending on the size of the trend, it usually takes at least 20 years for a signal to definitively emerge from noise, which is why climatologists took several decades before they definitively stated that the warming we've seen is real.
An objective scientist would conclude that we know too little about the climate
An objective scientist would know something about statistics and conclude that a few years of data does not magically overturn a century's worth of study of the climate. For instance, there was an analogous period in the 1940s where climate was warmer than models hindcast, but nobody says that mea