A quick post for commentary on the new Solomon et al paper in Science express. We’ll try and get around to discussing this over the weekend, but in the meantime I’ve moved some comments over. There is some commentary on this at DotEarth, and some media reports on the story – some good, some not so good. It seems like a topic that is ripe for confusion, and so here are a few quick clarifications that are worth making.
First of all, this is a paper about internal variability of the climate system in the last decade, not on additional factors that drive climate. Second, this is a discussion about stratospheric water vapour (10 to 15 km above the surface), not water vapour in general. Stratospheric water vapour comes from two sources – the uplift of tropospheric water through the very cold tropical tropopause (both as vapour and as condensate), and the oxidation of methane in the upper stratosphere (CH4+2O2 –> CO2 + 2H2O NB: this is just a schematic, the actual chemical pathways are more complicated). There isn’t very much of it (between 3 and 6 ppmv), and so small changes (~0.5 ppmv) are noticeable.
The decreases seen in this study are in the lower stratosphere and are likely dominated by a change in the flux of water through the tropopause. A change in stratospheric water vapour because of the increase in methane over the industrial period would be a forcing of the climate (and is one of the indirect effects of methane we discussed last year), but a change in the tropopause flux is a response to other factors in the climate system. These might include El Nino/La Nina events, increases in Asian aerosols, or solar impacts on near-tropopause ozone – but this is not addressed in the paper and will take a little more work to figure out.
Update: This last paragraph was probably not as clear as it should be. If the lower stratospheric water vapour (LSWV) is relaxing back to some norm after the 1997/1998 El Nino, then what we are seeing would be internal variability in the system which might have some implications for feedbacks to increasing GHGs, and my estimate of that would be that this would be an amplifying feedback (warmer SSTs leading to more LSWV). If we are seeing changes to the tropopause temperatures as an indirect impact from increased Asian aerosol emissions or solar-driven ozone changes, then this might be better thought of as impacting the efficacy of those forcings rather than implying some sensitivity change.
The study includes an estimate of the effect of the observed stratospheric water decadal decrease by calculating the radiation flux with and without the change, and comparing this to the increase in CO2 forcing over the same period. This implicitly assumes that the change can be regarded as a forcing. However, whether that is an appropriate calculation or not needs some careful consideration. Finally, no-one has yet looked at whether climate models (which have plenty of decadal variability too) have phenomena that resemble these observations that might provide some insight into the causes.
BTW, OT, but I went to see Book of Eli last night. Great movie IMO, but maybe a little too intellectual and spiritual for the common man (hence not taking in big $ at the box office). The post-apocalyptic image of the world gave me the shivers, though. It really looked like I imagine things would be if the worst of the worst of the worst came to pass in climate change (even though in the movie it was caused by a war).
Does anyone know if it would be possible to construct a special cross-journal membership for an area of interest, specifically climate change? I just don’t have the money to subscribe to every journal out there just to feed my interest in the subject (at least, not without opening a private account to hide the expenses from my wife). I already have too many expenses related to my career.
It frustrates me, though, to live on abstracts and summaries and BBC articles and blog posts.
Would journal publishers be open to this sort of idea? Does it exist already somewhere that I haven’t found?
[Response: AGU provides this for their journals (JGR, GRL, Paleoceanography etc.), but I don’t know of any cross-publisher effort. Sounds like a great idea though… – gavin]
@ 10, 40. Re: the recent Frank et al. paper. I just read the abstract (haven’t gotten full access here at home) but it certainly looks interesting. But it appears that this is about the response of the carbon cycle to increased temperature, meaning how much co2 is released from a warming earth. Think about that. Why isn’t it zero? This is about mechanisms (presumably) like melting permafrost and the like, which release CO2 into the air when warming occurs. I would think this is likely very state-dependent, meaning that at the depths of the last ice-age, their gamma number is different than today, or during the last glacial maximum, or the PETM, etc.
That being said, this effect they are reporting on I think is not to be confused with the “airborne fraction of co2” question, which is what fraction of the co2 that we emit into the atmosphere actually stays there, and what fraction is taken up by the earth (land and oceans) right away. my gut says the latter is just as important (if not more so) than the former, but I would have to see some hard numbers to back it up.
Finally, this in no way is central to the “theory of AGW” as one poster seemed to assert. It is more a sideline detail. Don’t get me wrong, perhaps this result buys us a bit more time. But remember most climate models to date have a static carbon cycle anyway; their 7 ppm /deg C number would make all models produce even more warming than they currently do!
I’m only at #3, so if my answers will soon appear, forget the questions. What is the [best] explanation for the 1-2 year drop in the stratospheric H2O? Since the measurements before ~2000 are looser, is it conceivable that, rather than a drop after 2000, 2000 is just a spike blip from steady decades preceding and after 2000? 2) What is the H2O breakdown in the stratosphere between droplets (clouds) and vapor?
Hank (#38): Yes, whatever happened to Lou Frank’s “discovery” of millions of small comets continuously entering the Earth’s atmosphere? As far as I know, it remains controversial after all these years, rejected by all but a very few researchers. The latest citation I could find to his work was a paper (2001) rejecting his claim of optical detection:
http://adsabs.harvard.edu/abs/2003JGRA.108e.SIA5M
Some interesting critical discussion at
http://www.williams.edu/Astronomy/jay/ETU4/chapter17.html
and see the recent paper by Francis and references therein:
http://arxiv.org/pdf/astro-ph/0509074
But Frank developed considerable evidence for his hypothesis, described by him in a lecture which can be read at
http://sdrc.lib.uiowa.edu/preslectures/frank99/index.html
A very interesting case. Anybody have any more info? (I believe that Frank is now emeritus at U of Iowa, where he was on the faculty for many years.)
Clarification to my comment #43: when I wrote that I read Solomon as saying that “there’s no excess heat accumulating,” I want to be clear that I’m talking only about the unaccounted excess heat in the last decade, not interpreting their result as conflicting with a long-term AGW trend.
Peter Coates asks in #26:
This sounds like there might actually be a significant negative feedback loop in the system too. And I was thinking that atmospheric methane was unmitigated bad. Is Gaia more forgiving than we give credit for?
I’m afraid you’re confusing a couple of things there Peter:( Gavin mentioned some of the causes of stratospheric water vapor, including methane.
Here’s the thing: we don’t (yet) know of any good causes why lower stratospheric WV declined 10%. Pekka Kosta provides some food for thought as to why there might not even be a decline. What we have so far is “This is very interesting. We need to look more closely at this”.
As for fortunate Gaiin negative feedbacks with methane – they aren’t. Methane that oxidizes in the stratosphere creates CO2 + H2O. Increasing arctic methane emissions then would seem an impossible cause of decreasing stratospheric H2O unless there’s some very interesting reaction going on between ground level and the stratosphere.
IF – and it’s a big if so far – the report is completely accurate it seems pretty scary to me. If a .5 ppmv decline in WV in a small slice of the atmosphere is enough to offset increases in CO2 it’s a very particular thing. Presumably, then, an increase of 1 ppmv would have the warming effect of two decades of CO2 emissions. That would make WV in the lower strat an extremely important thing to control.
I’m not scientist enough to sort that out, but it seems unlikely enough to me that I’ll wait for those who are to study it in more detail. My uneducated WAG is that it will turn out to not be very important. My uneducated WAG is that ocean storage + solar minimum is all that’s required to explain the “lack of temperature increases for the 2000s”.
david adam says: 30 January 2010 at 1:18 PM
For what it’s worth, I thought the article was well written, except for the irrelevant references to the TomskTwaddle email invasion, etc. Referring to the exciting and overstimulated political climate does not really help aid understanding of our physical climate, though it does liberate heat unaccompanied by light.
Also, I don’t really understand why contrarians would find this article to be something to celebrate. Water vapor is fairly uncontroversially predicted to be an important feedback source, this paper only seems to cement that as well as illustrate how powerful it is. It’s bad news, to me.
#55 It is my understanding thant Frank’s mini-comet makes absolutely no sense. We should see collision of them on the moon on a regular basis. This is an easy experiment and amateur astronomers do it on a regular basis in meteor shower. Also this as been ruled out by lunar seismometer.
#55 Frank’s comet impact on the moon would be as easy to spot as meteor showere impact, which are recorded by amateur astronomer.
> David Adam
Speaking as an ordinary reader here, thank you. Let us know if the headline and lede get clarified?
I know that’s hard. I nudged our local paper on an error about “sea level rise by 2100”–they fixed the mistakes online, noting only “This story has been corrected since it appeared in print editions.” Copies of the original with mistakes in both headline and text are still widespread.
> a special cross-journal membership
Do the newspaper and magazine writers get access to the full text science articles online, somehow?
One question I have regards air travel. I think I’ve read it somewhere that air travel is worse for GW, beyond its CO2 emissions, because it also emits water vapor fairly high up in the atmosphere, that more easily gets into the stratosphere.
Also there was a jet “contrails” issue some years back, and the difference was noticable when all flights in the U.S. were grounded on 9/11. But I can’t exactly remember what the issue was.
Yess, I read this with interest, I am particularly suspicious about the conclusion
that there has been a world wide cooling caused by the lack of water vapour at the tropical tropopause…. Something doesn’t compute, the tropics and Arctic are joined at the hip, and the Arctic aint a cooling.
Doesn’t any one have data on tropopause height anomalies at the equator, particularly if they have been rising lately (last 20 years)? I am thinking that it may be higher, http://physicsworld.com/cws/article/news/17937 ,
but the devil is in the details…
THIS bears repeating:
#22 More puzzles.
One wonders what is ahead if the hottest decade ever was cooled by a drop in stratospheric water vapour.
Comment by Tony O’Brien — 30 January 2010 @ 5:38 AM
RE #10, Jimbo, it would be interesting to see if denialists pick this up and run with it, bec they’d be admitting that CO2 feedback (I assume what they mean is methane and CO2 from melting permafrost & ocean hydrates) is not as fast as thought.
That’s sort of like geometrical progression of population. Anything greater than replacement value will eventually lead to a population explosion, only a smaller value will do this over a longer time period.
So if the article is correct then climate hysteresis (and doom to most of life on earth) or even runaway warming (and total doom to life on earth) will happen just a bit slower than previously thought.
Bob says: 30 January 2010 at 1:40 PM
If you’re an alumnus of a university or college you may find there’s a means to access many journals. Options vary depending on how much money is sloshing around at a particular institution, with many affording alumni full text electronic access to a broad swath of journals. Check the library site of your alma mater for more info.
re: comments #4 and #13
Concerning recent increases in the rate of methane emissions:
The link to the article in The Guardian is:
http://www.guardian.co.uk/environment/2010/jan/14/arctic-permafrost-methane
The link to the abstract of the article published in the January 15, 2010, issue of Science is:
http://www.sciencemag.org/cgi/content/abstract/327/5963/322
Ray Ladbury
I see that you are stumbling over my indigestible colloquialisms. I also see that you haven’t gotten over your habit of talking down to those who post here.
If I were a lukewarmer, I would use full-blooded warmist language to sneak my point of view across wouldn’t I?
What the authors do is analogous.
If the authors of this paper want a receptive audience, they have to allow the full range of uncertainties to stand – given the fact that there are many ever-ready with the “its just one paper” stick at hand. And that’s what they do.
Frank et al estimate γ (gamma) to be 1.7-21.4 ppmv CO2/ degree C warming. This range as such, covers a good number of models. Why would they knock other models down at all?
What they do accomplish is – they knock down the higher reaches of this range pretty confidently.
Regards
KLR (27) — Not a chance, directly. However, fairly rapidly removing a large quantity of ice would tend to either enhance or inhibit earthquakes and volcanoes which were about ready to go any thousand years or so. There is a spectacular flaut scarp in northern Sweden which might have been partly induced by the melting of the Fennoscandinavian ice sheet, for example. Anyway the dating is about right for that.
But in general even supereruptions, the last one being Mt. Toba, have only a short term impact; I at least can’t find evidence for it in ice core temperature proxies even though I know the date to within a thousand years or so.
Anand, What you fail to understand is that in REAL climate science, there are no “warmers” or “lukewarmers”. Believe it or not, to climate scientists, it is not about climate change. They are trying to figure out the climate. Period.
If their result holds up, That is good news. It is a single analysis of a single line of evidence AND they do have huge error bars that overlap with the currently accepted range. What is more, their analysis does not affect any of the previous analyses that constrain CO2 sensitivity. It is a matter of how the feedbacks break down more than the total feedback.
I would suggest that you ought to get a better understanding of the science if you want to see how this (very interesting) work fits in. And while you are at it, you might want to learn in general how science works. Your whole approach reminds me of Andrew Lang’s criticism: “He uses statistics the way a drunkard uses a lamp post–for support rather than illumination.”
And who are you to assign motives to the authors’ statements which in no way reflect what they actually say?
Useful discussion of this paper by Jeff Masters, particulary amplification on vapor transport:
http://www.wunderground.com/blog/JeffMasters/article.html
I appreciate David Adam’s interest in getting it as clear as possible. What I wondered about is this bit: “She said it was not clear if the water vapour decrease after 2000 reflects a natural shift, or if it was a consequence of a warming world. If the latter is true, then more warming could see greater decreases in water vapour, acting as a negative feedback to apply the brakes on future temperature rise”.
Seems like a stretch given the observed magnitude of the effect and question of how dry an already dry stratosphere can get. Maybe, more specifically, it could apply the brakes on some of the future temperature rise? Assuming this is actually a feedback to climate forcing and not just a response to internal variability (like what phase certain ocean cycles are in). If so, is there any mechanism that could explain a trend of less water vapor delivery to the lower stratosphere in a warming world?
[Response: I think it very unlikely that this could be a demonstratable negative feedback to surface warming. We know that upper tropospheric water vapour increases with surface warming (Minschwaner and Dessler etc.), and that water vapour moves up due to two things: the large scale uplift of air and penetrative convection (of both vapour and condensate). A drying of the lower stratosphere would have to be associated with either a decrease in the cold point at the tropopause (affecting the amount of vapour in the uplift), or a reduction in penetrative convection. There is no obvious reason why surface temperature increases would cause either effect. As far as I know (someone might want to correct me), all the stratosphere-resolving GCMs show increasing lower strat water vapour as a long term impact surface warming. – gavin]
I’ll repeat what I’ve already said:
The overall thrust of the Frank et al paper is that they propose constraints on CO2 sensitivity that shackle it to the lower quartile of the existing models’ proposed ranges.
They repeatedly state that sensitivities of ~40 p.p.m.v CO2 per C are unlikely.
They even venture gingerly to state that – “If γ were to have been invariant during the pre-industrial past millennium, these distributions may permit γ to be more tightly constrained to 2.2–12.7 p.p.m.v. per °C”.
They conclude in the end saying: “The convergence of γ computed herein with other more moderate values quantified for interannual to Milankovitch timescales suggests limited timescale dependence and thus reduced possibilities for unwelcome surprises within the next century. ”
They have necessary qualifiers in all the right places, of course. This is a well-written paper.
If you agree with the above statements, your original argument that “it (the paper) doesn’t preclude higher values with any sensitivity,” doesn’t hold much water, does it?
Knowing your style of argument, I’ll take your “If their result holds up, That is good news”. I didn’t come to this thread to make anything of this paper. I only wanted to counter your contentions
dhogaza: You ask – Who am I to assign motives?
I am not assigning motives. I am just saying that a good climate researcher will use well-tempered language in his/her work, like these authors do. Read my post again – does it look like I am calling any of the authors lukewarmers?
The paper is non-alarmist in tone and conclusion. Isn’t it a cause for worry for our more alarmist brethren in the AGW business? But it has their ear, certainly. That’s what I’m saying
The same Nature issue carries a small piece about the lead author – it makes quite clear which way he actually leans. Which is also immaterial to my point.
The authors state at several places there is limited understanding of the carbon cycle. To me that seems to fly against the face of “the science is settled” argument. The recent Science and Nature papers are both heartening, to that end.
Regards
Anand
Well it’s not quite clear what your point is Anand (something nefarious apparently), but tell the whole story if you’re going to tell it at all: Their very next sentence, right in the abstract, is:
“Our results are incompatibly lower (P,0.05) than recent pre-industrial empirical estimates of 40 p.p.m.v. CO2 per 6C (refs 6, 7), and correspondingly suggest 80% less potential amplification of ongoing global warming.
The authors aren’t in any way trying to hide the difference in their results from other studies. Be honest.
More on this later however.
Presumably , I haven’t read the full paper, we don’t know what the water content of the stratosphere was prior to 2000. Was 2000 a peak year? This would suggest it contributed to global warming in the 20th century or is there just a sudden drop in the last 10 years after decades of stability?
@27 KLR : as a seismologist in touch with volcanoes, I would say that the main force which is causing earthquakes and volcanoes is the residual heat of the Earth (backed up by natural radioactivity) – a change in Earth eccentricity would not have any effect on this internal cause (however, on Jupiter moons, the gravity field variations are strong enough to cause eruptions).
As for the comment 69, some people truely proved that the ice sheet melting is causing the Scandinavian uplift (no name in the head right now, but I did myself a few calculations about that) ; in the same topic, geological structures of sackung were linked to the glacier removal in the french Alps. The seismicity induced by these phenomena is however rather weak – maybe because Scandinavia was already full of faults ready to move …
Sorry for the off-topic, for once I can say something intelligent on this site :]
See also this 2006 report, which seems to cover the same topic, but points towards ozone changes in the tropical troposphere:
WJ Randel et al. (2006) “Decreases in stratospheric water vapor after 2001: Links to changes in the tropical tropopause and the Brewer-Dobson circulation”
Hello again – any comments on my previous comment (#9). I’d very much appreciate if anyone has any insight on this.
52, Bob: Does anyone know if it would be possible to construct a special cross-journal membership for an area of interest, specifically climate change?
I don’t know your budget or location, but you might try joining a library association. I joined the UCSD Library Committee (I forget what exactly it is called, maybe “Friends of Geisel Library”.) You can check out books, read articles for free, and print articles for low page fees. You can also read the “Supporting Online Material”, which for Science and Nature is more substantial than the printed journal article.
RE: 49
Hey Fred,
I am no expert, only a simple layman; however, I believe the issues in your observation has more to do with the three means of heat (LW) flow in the atmosphere, radiation, convection and advection. When we trace IR heat (LW) content via satellite observation we are observing the radiant heat (LW) content in the atmosphere to some spectral (wavelength) limited saturation depth. (Note: The more IR content at a specific wavelength the more opaque the atmosphere will be.)
When we consider the three basic heat (LW) flow pathways, radiation is the primary measure used to determine the Earths Atmospheric (LW) Radiation Measurement/Budget. Satellites are great for making this measure especially when coupled with ground station measures as the space/ground based combination can help determine the total content using sweeping Lidar systems. (The data provided by these tools are the primary feeds used in most climate modeling.) However, they do not track the flow of heat content (LW) or flow through the atmosphere. Unless you can tell the depth/content of the heat along with the direction of the flow you cannot be certain of the measured movement of heat in the atmosphere. (Hence you do not actually see the flow of LW or heat with these tools.) Generally, the primary means to track long term, high resolution, atmospheric heat flow is to observe the water vapor flow in the Troposphere.
Also where many of the models employ standard specific heat convection models I believe there may be greater variability then is normally accredited. (As an example the Richard Lindzen’s atmospheric iris theory may help describe the phenomena ( http://en.wikipedia.org/wiki/Richard_Lindzen ). The problem is, if you cannot measure/display this phenomenon you are not going to be able to prove it. (I have a pet theory that Mt. Pinatubo might have injected a high amount of water vapor into the Stratosphere that be partially responsible for some of the imbalance we have seen over the last 20 years.)
To me it appears that basic LW IR heat content in the Earth’s atmosphere is not zonal. (As opposed to what we seem to see in either Jupiter or Saturn) When the heat content in a lower zone exceeds some value the “excess” escapes (advects) towards the poles. (A clear example of this can be found in the variation seen in the Polar and ITCZ Jet Streams. Possibly also documented in recent papers regarding the decrease in the Walker circulation and increased Jet Stream deviations.)
The funny thing is that as the total atmosphere warms it seems that the Earth’s atmosphere becomes more zonal, to a point. (Observational examples can be found in tracking the apparent higher instances of stagnant Rossby (barometric pressure) Wave phenomena over the last 40 years. (Which I suspect are related to abnormal monsoons, heat waves and droughts.)) It appears to me that as the heat content reaches a certain point there is a massive release of energy. (Signaled by abnormal tropical storm phenomena.) With the result being the atmosphere achieves a new heat content plateau, as the polar regions warm and general stability seems to return.
The whole point being that there may be abnormal variations in atmospheric heat (LW) content that can be either man made or due to abnormal natural phenomena. The Earth’s atmosphere provides transport of this heat content that can exceed the zonal heat (LW) build up towards the poles. (As has been measured by both near Arctic Circle ground stations and NASA high altitude Tropospheric Arctic heat content measurements.)
None of these observations; however, change the basic facts that additional CO2 in the atmosphere increases atmospheric heat content. The recent work by Dr. Solomon does more to underline we have more work to do in the measurement of the content and the flow of the heat in the Earth’s atmosphere.
Cheers!
Dave Cooke
Stratospheric water vapor decline credited with slowing global warming
Posted by: JeffMasters, 6:18 PM GMT on January 29, 2010
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=1421
was certainly helpful to me!
Regarding the nature paper. To the extent it reduces our estimates of temperature/CO2 feedback, it only reduces very long term climate sensitivity (to current emissions). It is about CO2 in the atmosphere begetting more atmospheric CO2 on long (centennial or longer) timescales (if I got it right). The typically stated sensitivities are for a fixed amount of atmospheric CO2. Such feedbacks might change the CO2 versus time trajectory, but not the temperature versus CO2 curve.
“Response: The reaction above is overly simplistic (there are a number of pathways to oxidise CH4), but they all end up with water and CO2 (both CO and HCO are both oxidised in turn). – gavin”
Well. You show us the alternative pathways that you purport to exist and the peer reviewed literature they come from. I don’t take peoples word for things these days. The appeal to authority may work for some but not for me.
The fact remains that the equation you use in your post is for combustion of methane and is not the pathway for stratospheric oxidation of methane. You cannot use it as a schematic for the oxidation pathway as it represents a totally different reaction and is completely misleading.
Perhaps some of the atmospheric chemists out there can enlighten both of us.
Response: Now this is seriously wrong. There is no oxygen in methane, and so the creation of oxygen as a final byproduct is impossible. There is no precipitation in the stratosphere (except for a tiny amount of of PSC formation). – gavin]
You obviously did not follow the pathway I described in #17 above. I reproduce it for your benefit here:
CH4 + OH -> CH3 + H20
CH3 is oxidised by:
CH3 + O2 + M -> CH3O2 + M
CH3O2 + H02 -> CH3OOH + O2
(I incorrectly used H2O instead of HO2 in the equation in #17)
As you can see, oxygen is a final byproduct of the oxidation pathway of methane in the troposphere along with methyl hydroperoxide.
[Response: I have no clue what you are trying to demonstrate here. You use O2 in one reaction, and then it is a product in another. There is no net creation of O2. Thus to describe O2 as being a ‘final byproduct’ is like describing any catalyst as the ‘final byproduct’ of a catalysed reaction. Please try and discuss something sensible. – gavin]
46
Completely Fed Up says:
30 January 2010 at 1:11 PM
“RS: “You need the application of heat for the equation to progress”
Not really. As long as it is energetically favourable, you will get some combustion naturally.
And I note this is quite a departure from your earlier comment that CO2 was NOT (categorically and emphatically!) a product of methane combustion.”
You have it wrong as usual. I stated categorically that CO2 is not a product of the atmospheric (in the tropospere) oxidation of methane.
Oxidation not combustion.
[Response: You are wrong whether it is the troposphere or the stratosphere. And the level of wrongness (wrongitude?) is much worse for the stratosphere, which is in fact what we are talking about. – gavin]
The Stratosphere
“The stratosphere defines a layer in which temperatures rises with increasing altitude. ” ” This rise in temperature is caused by the absorption of ultraviolet (UV) radiation from the Sun by the ozone layer. Such a temperature profile creates very stable atmospheric conditions, and the stratosphere lacks the air turbulence that is so prevalent in the troposphere. Consequently, the stratosphere is almost completely free of clouds or other forms of weather.”
from Encyclopedia of the Atmospheric Environment
http://www.ace.mmu.ac.uk/
The Montreal Protocol on Substances That Deplete the Ozone Layer entered into force on January 1, 1989, -Wikipedia
Now the missing part is to look fore the changes in the ozone and temperature profile not only at Antaracica
48
Theo Kurten says:
30 January 2010 at 1:19 PM
“Richard, your equation
CH3O2 + H2O -> CH3OOH + O2
is wrong. Clue: the hydrogen’s don’t balance, nor do the oxygens. That should be
CH3O2 + HO2 -> CH3OOH + O2.”
You are correct of course. I only noticed the typo this morning. Thamks.
One of the signs of CO2 induced global warming is the cooling of the stratosphere, so it seems to me that a reduction of water vapor in the stratosphere would be expected. It is likely I do not understand the issue, at the moment I do not understand why the reduction of water vapor in the stratosphere in a mystery.
I thought that the temperature of the troposphere was controlled almost 100% by radiative heat transfer. This implies that heat transfer between the stratosphere and the troposphere is negligible, especially in terms of conduction, as the stratosphere is too thin and does not have much heat capacity.
Can someone please explain or direct me to an explanation…
[Response: Stratospheric cooling due to increasing CO2 is mainly an upper stratospheric phenomena, but doesn’t in itself affect the stratospheric water vapour amount directly. This is because there is no condensation to speak of (outside the PSCs in the deep polar vortex). There might be small indirect effects due to changes in circulation or indeed atmospheric chemistry, but these will be small. – gavin]
wrt methane oxidation, it mostly goes
CH4 + OH –> CH3 + H2O
CH3 + O2 –> CH3O2
(a) CH3O2 + NO –> CH3O + NO2
There are lots of ways to get from CH3O to H2CO formaldehyde
H2CO eventually goes to CO and CO oxidizes slowly to CO2
OR
(b) CH3O2 + HO2 –>CH3OOH which rains out, but, since there are no clouds in the stratosphere, this is only an issue in the troposphere. In the stratosphere, the CH3OOH will react eventually to form H2CO usw.
The rate constant for (a) is a bit faster than for (b) but the branching ratio is controlled by the availability of NO and HO2 respectively, which depends, on well, us mostly these days, (depending on where you measure NO is anywhere from 1 to 100 times more available than HO2, but a significant source of HO2 is NOx reactions. . . )
at most channel (b) removes half the CH3O2, at least a percent or so based on OOM thinking.
The very dryness of the stratosphere has been used to determine a limit on the incoming flux of comet-like material: http://www.agu.org/pubs/crossref/1998/98GL01229.shtml so it may be that variability in water content there has to do with the rather episodic interrelationship between the Earth’s orbit and the trails of comets. But, methane mixed into the stratosphere seems as though is must play an important role in what the base level of water vapor is and perhaps in its variability. And, the lower you go in the stratosphere, incursions of regular water vapor must become more important.
One can point to a long term effect of global warming on the composition of the stratosphere should the runaway greenhouse that Hansen has mentioned a few times now comes to pass as a result of burning all fossil fuels. It will become very wet along with the rest of the atmosphere.
Re Frank et al:
Why did they choose to re-calibrate the paleotemps to just the northern hemisphere instrumental record? They don’t explain. The paper is about a global phenomenon (carbon cycle amplification), so shouldn’t any recalibration be to a global temp series? And what did they do about that divergence problem? Again, they don’t say. Any recalibration ensemble members that include the divergence interval are going to be spurious, no?
Michael Andrews gives us the answer Susan Solomon couldn’t write for her paper published by Science on how stratospheric water vapor has decreased by 10% after the year 2000. He even attributes the answer to her!
This article is a “must read” for those having trouble deciding whether to laugh or cry.
Remember, George Will gets it here.
Dropping Water Vapor Levels are Naturally Negating Carbon’s Warming Effects
http://www.dailytech.com/Dropping+Water+Vapor+Levels+are+Naturally+Negating+Carbons+Warming+Effects+/article17553.htm
Michael Andrews – January 29, 2010
(excerpt)
“Despite the apparent bias of many climate researchers, they do have one thing right; carbon levels have risen notably over the twentieth century from about 300 ppm to 375 ppm. While still far from the estimated levels of around 3,000 ppm during the time of the dinosaurs (appr. 150 MYA), the rising levels do mark a legitimate trend. However, there is increasing evidence that the rising carbon, contrary to alarmist reports is actually having remarkably little effect on global temperatures.
“A new study authored by Susan Solomon, lead author of the study and a researcher at the National Oceanic and Atmospheric Administration in Boulder, Colo. could explain why atmospheric carbon is not contributing to warming significantly. According to the study, as carbon levels have risen, the cold air at high altitudes over the tropics has actually grown colder. The lower temperatures at this “coldest point” have caused global water vapor levels to drop, even as carbon levels rise.
“Water vapor helps trap heat, and is a far the strongest of the major greenhouse gases, contributing 36–72 percent of the greenhouse effect. However more atmospheric carbon has actually decreased water vapor levels. Thus rather than a “doomsday” cycle of runaway warming, Mother Earth appears surprisingly tolerant of carbon, decreasing atmospheric levels of water vapor — a more effective greenhouse gas — to compensate.”
Icarus,
I can’t think of any mechanism by which a slight change in Earth’s orbit shape could affect Earth’s volcanism.
yourmommycalled (#44) writes: “I not sure where Pekka Kostamo (#24) got that the time constant of radiosondes are on the order of minutes, because it is no where near close to being correct. I buy hundreds of Vaisala RS92-SGP’s a year. ”
Short googling reveals that at some point in time Pekka Kostamo was Vaisala’s Manager of Development Planning: http://www.vaisala.com/files/Ground-breaking_innovation_in_humidity_measurement.pdf
I would assume he knows what he is talking about.
Dutch quality newspaper NRC today runs an article on Solomon titled “Loss of water from stratosphere explains cooling of the earth”.
Some quotes: “The last couple of years the (average global) termperature even seems to go down a bit” (missed the NASA data, I guess).
“It is unfortunate that current climate models poorly describe temperature and water content of the stratosphere”.
http://bit.ly/NRCsolomon (in Dutch)
I’ve seen report that there are minor variations in the concentration of CO2 in the troposphere.
However, I’m curious as to how much variation there is in thru out the turbosphere.
Also, how much of an impact does the slowness of the mixing matter?
The stratosphere is supposed to be cooling because of rising CO2 levels, but won’t it eventually warm as CO2 becomes mixed up to 100km or so?
Thanks for any clarifications.
@ Jim Boulden
Well it’s not quite clear what your point is Anand (something nefarious apparently), but tell the whole story if you’re going to tell it at all: Their very next sentence, right in the abstract, is:.[..]
The nefarious part is this (?), I assume.
”
“3) It doesn’t preclude higher values with any sensitivity”.
Read between the lines, man – the way the authors put a non-sequitur like:
“Although uncertainties do not at present allow exclusion of y (gamma) calculated from any of ten coupled carbon-climate models…”
to buy ’street-cred’ for their contentions is hilarious. No one can exclude any of the present models – isn’t that fact?
”
I stand behind what I said. The authors say they cannot rule out any models and then go on to say they can state with statistical significance that the higher reaches of the models are unlikely to transpire.
And you are telling me that it is OK to use the first part of that sentence to imply the authors admit to overall uncertainty? Because that was what, was implied in Ray’s initial post. (#32)
If you think caveats cancel conclusions, no paper can make any sort of conclusion whatsoever.
And by the way, the authors do not want to ‘hide’ the differences between their probabilistic estimate for γ and the model estimates- they want to point out and stress the differences, and the fact that their values are ‘incompatibly lower’ than certain earlier ones. When did I imply that they were hiding anything anyway? Their findings run counter to alarmism.
Regards
Anand
#93 Remember, George Will gets it here. [dailytech]
And Anand, too.
http://www.anandtech.com
Andrew:
— not much; here’s a report of variation between 382-389 parts per million:
http://news.discovery.com/earth/satellite-sees-lumpy-layer-of-co2.html
— not much; the lifetime of CO2 in the atmosphere is decades to centuries
— start here
— FAQ