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.
Kees van der Leun, 31 January 2010 at 9:09 AM
You missed a [rather important] bit in the header and to let me quote with translation:
Amerikaanse en Zwitserse onderzoekers denken een verklaring te hebben gevonden voor de recente vertraging in de opwarming van de aarde. Het zou veroorzaakt worden door een daling van het watergehalte van de stratosfeer.
American and Swiss scientists think to have found an explanation for the recent slow down in warming of earth…
AMSU shows for the month of January a rather substantial increase in temperature of the different level in the troposhere, above the 20 highs for almost every single day of the month. Not sure Dr. Roy Spencer, who’s got his name printed under that web page tracking these temps is happy with that, in context with his little flick of switching to 25 months moving average… one I cannot correlate to anything at all even in imaginative atmospheric cycles… he should try 38 months [quasi ENSO] and then see how that pans out compared to that peek around 1998 and last several years… the end point is then over that super el nino event.
Sorry I’ve not had the willpower or time to read every word of every post here so this may have been said before:-
1. Interesting how AGW deniers support atmospheric computer models when they think it supports their case &
2. Has CH3OOH any global warming potential? (smile)
correction: “20 highs” should read “20 year highs”
A bit more detail for Andrew’s first question on how much CO2 varies, here:
http://svs.gsfc.nasa.gov/goto?3562
Excerpt:
“Moustafa Chahine, lead study author and AIRS science team leader at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., said the maps, which cover from September 2002 to July 2008, will be used by scientists to refine how climate models represent the processes that transport carbon dioxide within Earth’s atmosphere. ‘These data capture global variations in the distribution of carbon dioxide over time that are not represented in the existing models used to determine where carbon dioxide is created and stored,’ he said.
Chahine said the previous scientific consensus was that carbon dioxide was evenly mixed in the free troposphere, decreasing as you move farther south of the equator. ‘Our results show carbon dioxide there can vary by nearly one percent and that the free troposphere is like international waters—what’s produced in one place is free to travel elsewhere,’ he said.”
Anand, you are confusing two utterly different concepts–
CO2 sensitivity=degrees warming per doubling of CO2
and
gamma=additional CO2 from warming due to an addition of CO2
These are very different. The Frank article has no effect on the well constrained values for CO2 sensitivity.
I have a question about the Frank article. I’ve always assumed that the carbon cycle response to warming was constrained by the glacial interglacial cycles along the lines:
glacial-interglacial global temperature rise 5-6 oC
glacial-interglacial [CO2] rise ~ 190 ppm to~ 270 ppm
Therefore each oC of warming results in repartitioning of 15 – 18 ppm of CO2 into the atmosphere.
Since the transitions take a very long time (5000ish years), the climate system and its carbon cycle component will have reached equilibrium.
So my impression is that Frank et al have more or less reconfirmed what we already new, at least in relation to paleodata. Their analysis must be rather confounded by the uncertainty in true global temperature variation during the period studied (1050-1800 AD), the uncertainties in the response times of carbon cycle feedbacks, and the separation of natural and anthropogenic contributions to [CO2] variation, especially in the latter part of their analysis period.
And of course, the Frank analysis doesn’t preclude the expectation that rapid warming due to massively increasing greenhouse gas concentrations won’t overpower sinks and stimulate release of greenhouse gases from so far stable (or stablish) sources (tundra, methane clathrates, forests)…
Hank Roberts;
Thanks for the feedback; your first link is the article I recall seeing.
The CO2 variations in the mid-troposhere is between 382 to 389 ppm. The troposphere is only about 8 to 15km high. So, I’m guessing that mid-troposphere must be around half that height.
However, eventually CO2 will mix evenly to a height of about 100km. Mixing of the atmosphere above the tropopause is likely much slower than below since there isn’t weather as we know it.
What I haven’t been able to find is much information on what CO2 levels are at the 100km elevation.
I’m sure they aren’t nearly as high as 390ppm, but I don’t know. I’m also unsure as to how CO2 levels at the 100km elevation will impact water vapor levels in the lower elevations.
Again thanks for the help.
This is OT but can all you moaners who complain about how AGW proponents are all meany poopy heads please check out the comment section to this climate crock.
http://www.youtube.com/watch?v=WPA-8A4zf2c
Read some of it and then come back here and complain with a straight face…
Dave Cooke #81. Thanks for taking the time to write such a helpful response to my question.
Pertti Kellomäki says: (#95)
“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:”
I am aware of who Pekka is and if read the post you would have noted the sonde I spend $220 each on is the Vaisala RS92-SGP (read the post: note the manufacturer and model number). I am quoting from the calibration tables and product specification notes supplied by Vaisala for the RS-92-SGP. Which exactly why I raised the question
To those wanting to discuss the recent Frank et al paper here:
Try to hold off for a couple/few days–I will soon be putting a post up about it, time depending on Gavin’s plans. Mean time, please read the paper, and supplement if possible.
Watched it CFU. http://www.youtube.com/watch?v=WPA-8A4zf2c
little nit pick, Rep. Boehner at this point was not talking about the warming issue, but about the EPA ruling, that is why he mentions cancer and breath.
Otherwise good grapphics, level headed, but light arguments, which in my case is not a bad thing! :)
now here is an article that I haven’t seen discussed anywhere else, maybe someone here could get their teeth into this –
http://www.quadrant.org.au/blogs/doomed-planet/2010/01/a-simple-calculation
Andrew, if you will post the cites for the sources you _have_ found, it will help people figure out what you may want. Most of us here are just ordinary readers like yourself. Once you get to asking a clear and interesting question based on what you’ve read and summarized, you might get one of the climate scientists interested.
Google Scholar is a good place to start — look at a few of these and see what you find and let us know, if you feel like working on the question?
http://scholar.google.com/scholar?q=co2+ppm+%22upper+stratosphere%22
(I think you’ll find the words upper stratosphere appear properly inside double quotes in that search string, thanks to our guardian angels here)
That found for example
http://www.sciencemag.org/cgi/content/abstract/274/5291/1340
Looking at the papers citing that, from that page, turns up quite a few more references. Then you have to pare the list down by doing searches based on the keywords.
Offhand I don’t know what technology you’d be looking for that would sample the air at the altitude you want — but you can find it, assuming anyone has measurements from that altitude.
My impression is that CO2 changes rapidly across the whole atmosphere, within a percent or two — that paper cited above is about a 1 percent variation.
Anand says: 30 January 2010 at 6:26 PM
“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.”
Reading that, it’s hard to conclude other than the significance of the paper for you is all about politics, the superficial impression it will make. Like the pot calling the kettle black, so to speak.
Prasad Kasibhatla (9) — Kinda foolish to use statistically insignificant decadal “trends”; see Tamino’s Open Mind blog for several threads on this aspect of time series analysis. Even more so for shorter intervals.
The Solomon et al. paper clearly establishes a variation (decrease) in lower stratospheric water vapor. This ought to produce some sort of cooling effect, but I opine one cannot be very certain of the amount. Despite this small effect, the last decade was the warmest decade of the instrumental record.
I do not know whether my comment will survive here, but nevertheless
Ray:I am not confusing gamma with anything else. We are talking about the ‘carbon cycle sensitivity to climate’ – to make things explicit.
Doug:
The paper has political significance. That is not what I primarily intend to discuss. But the politics was already in play when I arrived – the significance of this paper was being downplayed. Why read my comments in isolation?
The authors of the paper themselves point out the constraints they are able to place on gamma in the “…policy-relevant multi-decadal to centennial timescales”. (in abstract)
Anand says: 31 January 2010 at 3:30 PM
“I do not know whether my comment will survive here, but nevertheless”
It never ceases to amaze me, people are constantly accusing this site of suppression of comments, yet even the briefest scrutiny reveals endless quantities of drivel and tosh patiently tolerated by the moderators. They’d be doing doubters a favor by employing a more slashing editing style.
“But the politics was already in play when I arrived – the significance of this paper was being downplayed. ”
I think perhaps you are confusing the comment thread here with actual scientific practice?
For my part I’m looking forward to seeing Solomon’s findings integrated into the general understanding of the climate. Identifying an apparent major influence on surface temperature variability is a “great leap forward”, if you want to use political words to describe the opportunity.
Anand: “I do not know whether my comment will survive here, but nevertheless”
Oh you’re so brave..!
Brave, brave Sir Robin…
“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.”
Nope, only the strawman “the science is settled” is broken. Then again, that is meant to be easily broken,
Tell me, Anand, does this change mean that the CO2 is no longer 390ppm?
Does it mean that CO2 doesn’t trap IR radiation around 15 um?
Does it mean that space now conducts heat?
No?
Then these are items still settled.
Seems to fly in the face of “the science is not settled” argument.
Lawrence Maclean – it seems from various papers that the temperature at the tropopause boundary between the stratosphere and the troposphere exerts a lot of control over stratospheric water vapor (SWV), and that ozone plays a role here. Low ozone correlates with low tropical tropopause temperatures, and hence with lower stratospheric water vapor, since that’s the main entry point.
Stratospheric water vapor was increasing in the 1990s – see Shindell (2000), “Climate and ozone response to increased stratospheric water vapor”, GRL
“The calculated water vapor increase contributes an additional ≈ 24% (≈ 0.2 W/m²) to the global warming from well‐mixed greenhouse gases over the past two decades. [1980-2000]”
That more or less goes along with what the current study found, from:
http://www.physorg.com/news183916084.html
“An increase in stratospheric water vapor in the 1990s likely had the opposite effect of increasing the rate of warming observed during that time by about 30 percent, the authors found.”
AS to why it reversed, there are some guesses. For more on the ozone hypothesis, see:
http://www.agu.org/pubs/crossref/2001/2001GL013000.shtml
Stuber et al. 2001 “Is the climate sensitivity to ozone perturbations enhanced by stratospheric water vapor feedback?”
It seems that changes in tropical convection could lead to changes in tropopause ozone levels, leading to cooling and less water entering the stratosphere – and there are also other factors, like the poor historical instrumental record of SWV, and the effects of Pinatubo and the 1997 El Nino,.
Some relevant bits on stratospheric water vapor in IPCC AR4 that may be helpful: changes
in atmospheric constituents/radiative forcings (2.3.7), more on
changes (3.4.2.4), models (8.6.3.1.1), observational constraints on
climate sensitivity (Table 9.3).
So the idea doing the rounds that scientists have hitherto “overlooked” a major factor in warming other than CO2 seems wide of the mark, as usual. The sizeable (but uncertain) radiative forcing from increasing stratospheric water vapour 1980-2000 (0.24 W/m2) found in Solomon et al. is not news either. As mentioned in the paper, Forster and Shine (2002) arrived at a slightly higher figure (0.29 W/m2).
But after a cursory reading of the above, I’m not clear on how much this factor is taken into account in existing attribution studies / estimates of climate sensitivity constrained by 20th-century observations. (Regarding the latter, I see e.g. that Knutti et al. [2002, 2003] take into account stratospheric water vapor, but only that from CH4 with a weak RF, and they seem to be an exception.)
So what impact would it have if the 1980-2000 effect calculated by Solomon et al. is correct, and turns out to be a natural variation, not a feedback? Would the anthropogenic signal get any harder to spot, would the lower range of climate sensitivity estimates get more likely, than current estimates?
And on the other hand, would the fact that the past decade is the warmest in the record, despite a sharp fall in stratospheric water vapor, point in the other direction, or is it too short a time period to count? (Is 1980-2000 long enough?)
I gather you were thinking of doing a more extensive post on this paper. Looking forward to it.
Leo G., Tom’s reserve estimates are about 15% to low for coal, and probably off by a similar factor for petroleum or natural gas. He doesn’t consider oil shale or tar sands at all. What is more, we have new techniques under development to increase recovery from existing fields and new oil fields are being discovered. I also think his estimate of 50% of CO2 going into the oceans in perpetuity is rosy to say the least. My estimate is that we could be above 1000 ppmv by century’s end if we burned everything.
David Benson (115) – yes, I understand that obs. show a decline in lower stratospheric water vapor. But paper also argues that some portion of the ‘flattering’ in the obs. warming trend can be explained by this decline in lower strat water vapor – I realize that decadal ‘trends’ may not be statistically significant but nevertheless the paper focuses on the ‘flattening’. And so my questions was – does Fig 3b provide adequate
support for this assertion in the paper?
Anand, I was not downplaying the paper. I was arguing caution against placing too much credence in a single study and pointing out the FACT that the error bars are large and in fact overlap conventional estimates. I think the paper is good and creative work–that doesn’t mean that it is flawless or that it will even hold up. To know that, we’ll have to wait for confirmation from other studies.
I also pointed out that the study does not place any additional constraints on CO2 sensitivity–and that (along with emissions) is the central quantity that determines how deep we’re in it.
Prasad Kasibhat;a (123) Figure 3b is behind a paywall for me, so I can only reply in generalities; I’m skeptical that a mere decade can show much of statistical significance. That is, of course, d8ifferent from an understanding that variations of stratospheric water vapor will, in fact, impact climate.
By looking at Figure 2 from
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=1421
I see what might be a decadal “flattening” of tropical SST anamolies but I know enough to know that pink hoise can easily fool the eye; use sound statistics before declaring a trend.
If we stay just at current fossil fuel consumption levels for 50 years at ~2.0 ppm/yr, that’s obviously going to lead to 480 ppm in 50 years, and 580 ppm in 100 years – and a 3-4 ppm increase rate gives as much as 750 ppm – and that’s a likely rate if coal & tar sand use expands. (The “2X CO2” value is 550 ppm.)
http://www.esrl.noaa.gov/gmd/ccgg/trends/
Can we avoid these increases while continuing to burn fossil fuels? (No) Do we have to take into account the melting permafrost? (Yes):
http://www.nature.com/nature/journal/v459/n7246/full/nature08031.html
“They find significant losses of soil carbon with permafrost thaw that, over decadal timescales, overwhelms increased plant carbon uptake at rates that could make permafrost a large biospheric carbon source in a warmer world.”
So, what is the best place to put government resources, considering these facts? Is it here?
Illinois ‘clean coal’ plants await their fate, By Jeffrey Tomich, ST. LOUIS POST-DISPATCH, 01/31/2010
Energy Secretary Stephen Chu is expected to make a final decision in the coming weeks whether to go forward with the project. The Department of Energy last spring agreed to move forward with FutureGen on a contingent basis.
Before FutureGen gets the green light, the federal government’s private partners — a group of coal companies and an electric utility known as the FutureGen Industrial Alliance — must trim costs, attract more private or foreign government investment and otherwise fill in any remaining funding gaps. Over the weekend, the group enlisted a new member. Illinois Gov. Pat Quinn announced Saturday that Chicago-based power company Exelon Corp. will join the FutureGen alliance…
So far, the DOE has committed $1.07 billion to the project, mostly from last winter’s stimulus bill. The FutureGen alliance is expected to contribute $400 million to $600 million over several years.
The funny thing is, these “clean coal” projects will do anything to even slow the transfer of fossil carbon to the atmosphere, relative to power generation – and yet no similar-scale solar or wind projects are being funded to the tune of $1 billion.
Curious, isn’t it? How does oil and gas drilling offshore, more tar sand imports, and an expanded coal program fit with the stated desire to cap fossil CO2 emissions?
Shouldn’t all these fossil fuel expansion programs be blocked, rather than subsidized? Or, what is the Obama administration thinking? What kind of scientific advice are they getting on energy?
LeoG – no contradiction in that article with what the climatologists are saying.
Whatsisname there is counting only “proven oil, gas and coal reserves. … ‘generally taken to be those quantities that geological and engineering information indicates with reasonable certainty can be recovered in the future from known deposits under existing economic and operating conditions’.”
Compare just as one example, you can find others:
Annual Review of Energy and the Environment
Vol. 22: 217-262 (Volume publication date November 1997)
(doi:10.1146/annurev.energy.22.1.217)
AN ASSESSMENT OF WORLD HYDROCARBON RESOURCES
Institute for Integrated Energy Systems, University of Victoria
and International Institute for Applied Systems Analysis
” …If the vast unconventional hydrocarbon occurrences are included in the resource estimates and historically observed rates of technology change are applied to their mobilization, the potential accessibility of fossil sources increases dramatically with long-term production costs that are not significantly higher than present market prices….. neither hydrocarbon resource availability nor costs are likely to become forces that automatically would help wean the global energy system from the use of fossil fuel during the next century.”
I flat out don’t see nor read a ” slow down global warming by 25% between 2000 – 2009″ as per Dr Masters page:
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=1421
What I see is less strong El-Ninos for 2001-2009:
http://www.esrl.noaa.gov/psd/people/klaus.wolter/MEI/
Which should affect equatorial surface temperatures more than a cooling in the stratosphere (due to lower RH at the tropopause), by a factor of 5. This 25% cooling equation result doesn’t jive, it would be observed as a disparity at the equator mostly, I calculate equatorial ( GISS data for latitudes 24 North-24 South) surface temperature anomaly of +.30 for 1990-2000 while its +0.44 C for 2001-2009. Dr Solomon needs to explain where this cooling has occurred. If she means its near the Stratosphere, she may be right, yet that doesn’t slow Global Warming, but is as #73 Gavin statement infers part of Global Warming.
causing
Over at Skeptical Science John Cook came out with a piece on the decline of stratospheric water vapor that includes the following two take home points:
in #119 CFU wrote:
“Tell me, Anand, does this change mean that the CO2 is no longer 390ppm?
Does it mean that CO2 doesn’t trap IR radiation around 15 um?
Does it mean that space now conducts heat?
No?”
the first two points that have never been argued by any skeptic. i noticed you stopped there though. the next few questions that flow from that thinking are the big ones. do all these facts cause the planet surface temperatures to increase? and if so, when will it stop? will we turn into venus? it just seems that the AGW arguments are falling apart a little more every day. i fear that in a couple of years skeptics will be calling AGW proponents ‘deniers’.
gary thompson says: 31 January 2010 at 8:20 PM
“it just seems that the AGW arguments are falling apart a little more every day.”
How about a list? Anything specific?
No Gary, AGW arguments are not falling apart. The science of AGW is advancing through findings like this. That is a good thing. But there is only so much water vapor in the stratosphere, so this effect is bounded, even if it turns out to be a negative feedback, rather than internal variability. Meanwhile CO2 and its heat trapping capacity will continue to grow, as will the positive feedbacks, some of which, like methane release, are barely underway. This is not likely to be the wished-for silver bullet. By the way, we all wish there was such a thing. I feel sad as I think about the world awaiting my soon to be born great-grandson.
RE- Comment by gary thompson — 31 January 2010 @ 8:20 PM
What the three points you cite suggest is that global climate temperature should rise commensurate with the level anthropogenic addition of CO2 to the atmosphere. Temperature increase will stop when the increase in greenhouse gasses stop increasing and the subsequent equilibrium balance of incoming and outgoing radiation is achieved. Whether or not a Venus atmosphere could ever be achieved with available carbon sources is debatable. I don’t see how this causes current scientific evidence to fall apart. Perhaps you don’t understand how heat escapes our atmosphere. Please provide more information.
Steve
Timothy Chase says: 31 January 2010 at 8:20 PM
“Over at Skeptical Science John Cook came out with a piece on the decline of stratospheric water vapor that includes the following two take home points…”
John Cook is a very talented person, that is one terrific site. Cook employs a more formally pedagogical approach with his explanations than does RC, so quite apart from countering skeptical arguments it’s a useful place for getting up to speed on a broad array of climate inputs if you like your lessons in discrete doses.
Skeptical Science’s take on the Solomon 2010 paper and misconceptions running through blog world.
http://www.skepticalscience.com/role-of-stratospheric-water-vapor-in-global-warming.html
“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”
Where am I wrong in my statement? CO2 is not a byproduct of the tropospheric oxidation of methane. It may result as a breakdown product of the oxidation of the methyl hydroperoxide after it precipitates out of the atmosphere. There is not CO2 produced in the oxidation of methane in the troposphere.
“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]”
I stand corrected on this one issue.
Doug:
It never ceases to amaze me, people are constantly accusing this site of suppression of comments, …
They’d be doing doubters a favor by employing a more slashing editing style.
Completely Fed Up:
Oh you’re so brave..!
Brave, brave Sir Robin…
Will you guys take your blinders off and cool it a bit!
I wondered whether my post would survive here, as in this thread. The previous time I posted, there was just a comment from Jim Boulden saying he would create another thread for the Frank et al paper.
I wonder the same about this comment too.
And Doug, the ‘drivel and tosh’ that you refer to, I think I got my point across (see Ray L’s response above) and you don’t know what I was talking about. I don’t have a problem following a line of argument, despite how unwieldy RC is.
Completely Fed up: Why are you talking about CO2 heat trapping, aka the GHG effect? Can you point out where, in this thread, I talk about it at all? I thought I was talking about gamma – the CO2 change with temperature, and feedback effects thereof.
Ray: The paper states –
The higher values for γ during the late period result from the strong LIA CO2 dip around 1600, whereas the low values during the early period are associated with less variable CO2 fluctuations.
Does this imply that, for some reason, if temperatures were to drop or stay steady for long periods in the upcoming future, there exists the possibility that CO2 levels would fall precipitously?
Regards
Anand
Anand 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.”
Let’s not forget the big picture in all this.
So you don’t care about positive feedbacks? Something (most likely) rapidly jacked up the Earth’s surface temps during the PETM no matter how you slice CO2 sensitivity.
Remember too, that current climate models have a real hard time getting the high paleo-estimated temps just using paleo-estimated CO2 amounts (if they are accurate). This could certainly suggest unaccounted-for postive feedbacks way beyond CO2 sensitivity alone and are possibly a real cause for concern.
Ray and Hank, thanx.
Ron Taylor, congrats! My parents have 3 great grandchildren.
Richard Ordway:
My statement
“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”
should read
The overall thrust of the Frank et al paper is that they propose constraints on CO2 sensitivity to temperature that shackle it to the lower quartile of the existing models’ proposed ranges.
When I said CO2 sensitivity, I meant CO2 sensitivity to temperature levels. Thought it was clear enough in the context of the Nature paper.
“So you don’t care about positive feedbacks?”
Of course I do. But the paper suggests that γ in times of warming can be quite lower than γ in times of cooling. And therefore the strength of positive feedbacks.
I think this paper on water vapor in the lower stratosphere modulating climate change is an appropriate time to re-introduce the concept of unregulated coal fire power plant particulate emissions and their influence upon climate change. Water vapor condenses upon particles forming droplet nuclei an endothermic reaction. Such a phenomenon would produce a “cold point” leading to further water vapor precipitation. As Pacific warm water is transported to the lower stratosphere by cyclones and thunderclouds, so too particulates would be transported, fractioned by the violent uplift, and form water droplet nuclei simultaneously raining out water and cooling at a boundry layer forming a cool point hypothesized by Soloman et al. With the impending launch of the aerosol sensing satellite (hopefully it doesn;t meet the same fate as the CO2 sensing satellite), measurements of particulates, their size and distribution may provide greater insight. Coal fire emissions blunting the effects of rising CO2.
Anand Rajan KD says: 31 January 2010 at 9:57 PM
“And Doug, the ‘drivel and tosh’ that you refer to, I think I got my point across…”
Please, relax. The D&T I was referring to was not yours, or not much at all; the only hint I got of that sort of malarkey from your posts was where you began veering away from science and into politics. You did not mention “Al Gore” even once, nor did you mention taxation as though it was a dirty word, nor did you suggest that we are naturally suited as hunter-gatherers and must accept that useful technologies such as transistors are an unnatural, evil and temporary feature of our lives, nor did you say that if a single glacier is advancing that anthropogenic climate change is disproved, nor did you blame everything on mysterious, statistically invisible 60 year climate cycles.
All those vapid things and a myriad more you can find here on RC, which was my evidence suggesting that rumors of suppressed comments are just that. As far as I can tell the only thing that gets summarily sliced here is empty personally directed invective.
Re:137 Richard Steckis says:
31 January 2010
“I stand corrected on this one issue.”
Well… I can understand anyone’s less than perfect understanding of the atmospheric life span of CH4 and what happens to it in the troposphere and stratosphere.
Gavin wrote: “…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 )”
I’m sure this is correct. But I can’t find it in the literature. I’m sure it’s my fault. But I’d like to have an accessible reference that explained how CH4 oxidizes into CO2 in about 15 years.
CH4 has a global warming potential of 21. Then the carbon loses the hydrogen atoms and gains 2 oxygen atoms through oxidation. The global warming potential goes to 1.
How exactly does it do this? Does it have something to do with absorbing infrared radiation? Or UV radiation? What are the various pathways CH4 oxidizes? We’ve seen
a few alluded to. But there must be a paper that explains this. (I can’t access the citations Gavin supplied.)
Richard Steckis says: 31 January 2010 at 9:36 PM
So what? Upshot:
“The concentration of methane in the atmosphere is regulated by the balance between sources and sinks. A sink is something that absorbs, destroys, or removes gases from the atmosphere.
…
The primary sink for methane is the atmosphere itself which contains free hydroxyl (OH) ions. Once released into the atmosphere, methane undergoes a chemical reaction in the troposphere (lower region of the atmosphere), combining with hydroxyl ions to form water vapor and carbon dioxide.
http://www.epa.gov/nitrousoxide/pdfs/ffa.pdf
#131 Doug Bostrom “How about a list? Anything specific?”
as far as evidence of the AGW theories falling apart i point to observations over the past 10 years. we haven’t continued to warm, hurricane activity has not increased, droughts and famine are not happening, north american/europe are in the grips of the worst winter in recent memory, etc. i keep hearing that i can’t focus on a small time slice of 10 years to negate the trend over the past 30 years. ok, i agree with that. but just because the data doesn’t support the hypothesis is no reason to throw it out. what possible negative feedbacks are coming into play to negate our CO2 caused warming? as to a nice article to read on this, here is one –
http://www.co2science.org/education/reports/hansen/hansen.php.
this was written over 2 years ago so i’m sure you guys have already seen this and debunked it but it looks pretty sound to a lay person. i’ve stated before that the GISS weather station data doesn’t match the trends and graphs that are cited on the website and various reports and others have written detailed analyses of this which i’m sure you’ve read as well.
#133 STeve Fish “Whether or not a Venus atmosphere could ever be achieved with available carbon sources is debatable. Perhaps you don’t understand how heat escapes our atmosphere. ”
yes, i don’t understand fully our climate system on earth and i do admit my ignorance there. many of the people on this site have forgotten more about climate science than i’ll ever know. i’m trying to learn more but my day job isn’t in climate science and that plus by two rugrats keep me busy so there is a limit. that is why i come to this site to learn. but when i hear dire predictions about our planet and then observations
don’t match that i get frustrated when there are few real explanations of this. so are you saying that the narrow IR absorption spectrum of CO2 can turn our planet into a venus-like atmosphere? if you say it is debatable then there are some that think this. if so, then when will we reach those temperature levels given our current CO2 production?
sorry if my posts sometimes sound rude and mean spirited but i’m just frustrated – i can only imagine that you in the industry are orders of magnitude more frustrated. i enjoy the free exchange of knowledge and data and wish we could rise above the fray – i know i’m all too guilty of not doing that. i really mean no ill will toward anyone and will try and keep the posts related to the science and not the politics.
Over the last two days I have been monitoring the Wall Street Journal. Specifically the comments section for the article “Slowdown in Warming Linked to Water Vapor” – referenced earlier.
I have noted that at least a half dozen comments from scientifically literate people explaining the science of global warming – explaining radiative equilibria etc. have one by one been deleted by the Editors.
What remains is almost pure denialism.
SO the correct take away message here is that it is unwise to make claims about planetary or regional climate and weather based on short term (<30 year) changes in the signal? There are a variety of cyclic forcing factors that will sometimes catalyze and sometimes negate the other forcing factors. These cycles are on the order of a decade or more. CO2 is a minor player in these cycles, albeit constantly upward. Therefore teasing out the short term and/or impacts of CO2 is akin to "pulling monkeys out of the netherworld".
“Will you guys take your blinders off and cool it a bit!”
Bewails the man who “bravely” started their epic post with “this probably will get thrown out” complaint.
OPEN YOUR EYES.
gary: “the first two points that have never been argued by any skeptic.”
Wrong.
There are still PLENTY who argue those two points are wrong, pointing to Beers Law or G&T’s paper “proving” that the greenhouse effect breaks the laws of thermodynamics.
You’re pretty unclued-in on your side’s arguments, gary.
I also note that you stopped before the statement at the end:
Those two points in your eyes being settled goes against the denialist meme of “the science is not settled”, doesn’t it?
Well?