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From Peru at 03:14 AM on 3 February 2010The role of stratospheric water vapor in global warming
There is some discussion about a "slowdown" in Global Warming after 2000. What slowdown? In surface air temperatures the "slowdown" was an artifact of the 2007-2008-2009 La Niña. Now that it is over, we are back to record-breaking temperatures. In Sea Surface temperatures instead, there IS a flattening of trends after 2000. Also in upper 700 m Oceanic Heat content after 2003. As oceans absorbs most of heat, this indicates a slowdown in Global Warming? The answer seemed to be yes, until the paper of Von Shuckmann(2009) "Global hydrographic variability patterns during 2003-2008". It found a warming trend of 0.77 +- 0.11 W/m^2 in oceans DOWN TO 2000 METERS. Sp for some reason nearly all the heat accumulated below 700 m. Most of deep warming occurred in the North Atlantic, so I guess the reason was a strong Atlantic Meridional Overturning Circulation (AMOC) that subducted nearly all the heat to the Deep Ocean. Another evidence against slowdown in OHC trend is sea level rise. The mean trend for 2000-2009 is 3,3 mm/year. According to the Cazenave et al paper (2008) "Sea level budget over 2003–2008 (A reevaluation from GRACE space gravimetry, satellite altimetry and Argo)" the ocean mass contribution to sea level rise was near 2 mm/year. So, let's calculate the termo-steric SLR rate: Total SLR - Ocean mass SLR contribution = Thermo-steric SLR (3,3 mm/yr)-(2 mm/yr)= 1,3 mm/yr This is the thermo-steric SLR for 2003-2008 period. For 1993-2003 period the thermo-steric SLR was 1,2 mm/yr, according to the J. I. Antonov, S. Levitus, and T. P. Boyer 2005 paper "Thermosteric sea level rise, 1955–2003". So we have for thermo-steric SLR the following: 1993-2003: 1,2 mm/yr 2003-2008: 1,3 mm/yr There is no sign of slowdown. The rates of SLR were almost equal. The conclusion is that the ocean still absorbs heat, with no sign of slowdown. If upper 700 m show no trend, then the heat must have been accumulated below. Any idea why most of warming occurred below 700 meters? AMOC Themo-Haline Circulation? -
Chris G at 02:31 AM on 3 February 2010The role of stratospheric water vapor in global warming
@yocta, #11 ++ I think water vapor has a short enough lifetime in the atmosphere that it is better to ask the question as, "What caused the change in balance?", rather than "Where did it go?" Also, I found David Archer's book, Global warming: understanding the forecast to be in the right spot for me from a technical difficulty vs. comprehensibility standpoint. John, just wanted to say thanks for keeping this site up to date and well moderated. I often engage in climate debate in the local paper, and it is so much easier to link and say, Bob #8, Jim #12, than it was to keep repeating the same arguments and counters continually. This site would not be as useful if it were filled with insults. -
neilperth at 02:19 AM on 3 February 2010Lessons from the Monckton/Plimer debate
Chris re your comment : "The first reconstruction that covered the period of the MWP (just!) was Mann et al (1999) [****]. This analysis does show an MWP. Their warmest period (around 1150 AD) showed a temperature anomaly of around 0.1 oC (compared to the mid 20th century value of around 0.2 oC). i.e. the MWP max was around 0.1 oC cooler than the mid-20th century value." Is it really possible to measure the Earth's mean temperature to within an accuracy of 0.1oC as you seem to imply by this statement ? Especially when the MWP was hundreds of years ago. -
Marcel Bökstedt at 02:16 AM on 3 February 2010The role of stratospheric water vapor in global warming
It seems that the textbook "Principles of Planetary Climate" is not online any more, and also not available in print until summer.Response: Whoops, just noticed that and noted it in my response above. Thanks. -
sbarron2000 at 02:02 AM on 3 February 2010Lessons from the Monckton/Plimer debate
Chris, You're clearly right about Mann et al 1998. Mea cupla to that. That's what I get for skimming all these documents rather than reading them. -
chris at 00:23 AM on 3 February 2010Lessons from the Monckton/Plimer debate
That's not correct sbarron: (1) Mann et al 1998 used proxies going back only 6 centuries (to 1400) [*] The McIntyre/McKitrick (MM) "critique" analysed data going only back to 1400 [**] Since Wahl and Ammann were addressing very specifically the original Mann analysis and the critiques of MM it was obviously appropriate to use the same data and same analysis period. That's obvious I would have thought. So no "goal posts" were "moved". (2) The question of the MWP is an entirely different matter and is not part of the methodological disagreements (which came down rather strongly in favour of Mann and against M&M as Wahl and Ammann showed in great detail [***]). The first reconstruction that covered the period of the MWP (just!) was Mann et al (1999) [****]. This analysis does show an MWP. Their warmest period (around 1150 AD) showed a temperature anomaly of around 0.1 oC (compared to the mid 20th century value of around 0.2 oC). i.e. the MWP max was around 0.1 oC cooler than the mid-20th century value. If one compares this with the reconstruction showing the most historical variability (Moberg et al (2005) [*****], the latter shows an MWP max of around 0 oC compared to a mid 20th century value of around 0.2 oC. In other words the MWP was (in Moberg's analysis) around 0.2 oC cooler than the mid-2th century value. So I don't think one could say that Mann's paleoreconstruction doesn't show an MWP. Their MWP was pretty much equally as warm relative to the mid 20th century as Moberg's which is the most variable of all the reconstructions. Where Mann's 1998/9 reconstructions differ from Moberg's is (a) they don't have data pre-1000 AD. This is substantially cooler in Moberg's reconstruction (temp around -0.3 to -0.4 cooler than MWP), and is partly what makes the MWP "standout" somewhat in Moberg's analysis. Mann et all might have come to a similar conclusion if their analysis went further back...but it didn't. Secondly, Moberg shows a larger temperature decrease to the LIA (down to around -0.7 oC relative to mid 20th century baseline), whereas Mann et al decreases to only around -0.5 oC relative to mid 20th century baseline. Which of these is closer to reality? I don't think we know do we? [*]Mann ME, Bradley RS, Hughes MK (1998) Global-scale temperature patterns and climate forcing over the past six centuries Nature 392, 779-787 [**] Mclntyre S, McKitrick R (2005) Hockey sticks, principal components, and spurious significance. Geophys Res Lett 32:L03710 and a 2003 paper in the magazine Energy and Environment [***] Wahl ER and Ammann CM (2007) Robustness of the Mann, Bradley, Hughes reconstruction of Northern Hemisphere surface temperatures: Examination of criticisms based on the nature and processing of proxy climate evidence Climatic Change 85, 33-69 [****] Mann ME, Bradley RS, Hughes MK (1999) Northern hemisphere temperatures during the past millennium: inferences, uncertainties, limitations. Geophys Res Lett 26:759–762 [*****] A. Moberg et al. (2005) Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data Nature 433, 613-617 -
sbarron2000 at 22:49 PM on 2 February 2010Lessons from the Monckton/Plimer debate
chris at 08:11 AM on 31 January, 2010 The goal posts were moved from Mann 1998 to Wahl ER, Ammann CM (2007). Mann 1998 used proxies to show temps going back to 1000 AD. Wahl ER, Ammann CM (2007), and most later supports of Mann 1998 that I have seen, only address temps from 1400 to the present. I hear a lot of arguments from Mann's supporters like, "Mann's basic premise has been proven sound." The basic premise, I guess, being that its warmer today than it was during the Little Ice Age? I'm not sure that too many people, including McIntyre, have argued this point. The reason McIntyre even looked at Mann's 1998 hockey stick chart was because it showed no MWP. I won't speak for the guy, but I'd guess he feels vindicated that Mann and his supporters changed their argument to a time period that they were better able to scientifically prove. So why would he need to say anymore on the matter? -
Philip64 at 21:58 PM on 2 February 2010The role of stratospheric water vapor in global warming
"I've been deleting a great number of comments lately (from both sides of the debate)." John, this is off the topic in hand, but I'd be interested to know if you've been getting more intemperate posts than usual. If so, I think it's an unfortunate but inevitable accompaniment to the site's success, both in terms of reaching people and in terms of the quality of its content. I fear it is also because an increasing numbers of newspapers and columnists have been weighing on one side or the other. In some cases the polemic has been frightening. One notorious British columnist last week published (on his official newspaper blog) the name, address and phone number of a man who had written to one of his prospective parliamentary candidates, asking him to clarify his position on the climate change issue. The columnist took down the post after 12 hours or so and apologised, but not before the man had been telephoned and visited by people hostile to what he had done. Amazingly, the columnist, who works for the Daily Telegraph, has not been disciplined.Response: I do seem to be hitting the delete link a lot lately. And what's surprising is I seem to be deleting "pro-warming" comments just as much or more than skeptic comments lately. The debate is intensifying and everyone is getting a little excited. It's at this time more than ever that we need calm voices pointing us back to the science. -
Berényi Péter at 21:53 PM on 2 February 2010The role of stratospheric water vapor in global warming
@30/Response: "A good discussion on possible mechanisms can be found at the Wunder Blog" The discussion there is good indeed. This is why data homogenization is impermissible if metadata are absent. Sudden shifts do occur: http://www.wunderground.com/hurricane/2010/strato_temps_SST.png However, it is routinely done to datasets in mainstream climate science, both to surface temperatures and upper troposphere radiosonde humidity values. Looks like actual climate does have jumps, sometimes even in the downward direction. Time to reconsider automatic pattern recognition based data enhancement. If meaningful structure is removed this way, one may be left with pure noise plus a spurious trend. I am still waiting for references to peer reviewed papers on data homogenization as a legitimate statistical procedure. -
HumanityRules at 20:50 PM on 2 February 2010The role of stratospheric water vapor in global warming
John if you plan to present what the paper actually says you should be careful with your language. "They observed a slight increase from 1980" "a significant drop in stratospheric water vapor around 2000" Now lets see what the paper says. 1980-2000 increase of 1ppm (supported by increase of 0.5ppm during 1990s) After 2000 drop of 0.4ppm How can an increase of 1ppm be slight while a drop of 0.4ppm be significant? "In fact, what this paper shows is the effect from stratospheric water vapor contributes a fraction of the temperature change imposed from man-made greenhouse gases." What is that fraction? Well based on actual satellite data it's ~40% of CO2. Quite significant impact on radiative forcing over the period of measurement. They also modelled the maximum increase over the whole of the stratosphere and effect was "close" to CO2 "This seems to speak against the possibility of a negative feedback." Whether there are negative feedbacks to climate change I'm not sure. This just speaks against this being the mechanism. What it does speak for is the fact that potential natural variation can have a significant impact on radiative forcing (at least on the decadal level). And secondly that there are processes out there for us still to discover. The equation is still not complete. You can complain about some blogs overstating this but please don't understate it either. -
Arkadiusz Semczyszak at 19:41 PM on 2 February 2010The role of stratospheric water vapor in global warming
For me, here, an interesting is idea another scientific outsider: http://climatechange1.wordpress.com/2009/02/04/a-cooling-story-involving-ozone-the-sun-and-the-sea/ P. S. I appeal for failure to use - here; the concept of denialism - comparing a de facto, denial of the Holocaust - is simply unethical. -
RSVP at 17:40 PM on 2 February 2010The role of stratospheric water vapor in global warming
typo in fourth paragraph Says Figure 2, should be Figure 3.Response: Fixed, thanks for the tip. -
Albatross at 17:28 PM on 2 February 2010The role of stratospheric water vapor in global warming
Regarding changes in levels of SWV, did the authors consider tropopause folding as a mechanism for adding or removing WV to/from the stratosphere? For example, analysis of reanalysis data could be used to identify the frequency of these events and see if there is any connection. Have aircraft changed their cruising altitudes for some reason? Just some thoughts. ReJohn's comment at #30. I think Santer has done research which has shown that the height of the tropopause has been increasing in step with the tropospheric warming. -
carrot eater at 15:47 PM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
Leo G: Yeah, I see that context. desmogblog had a poorly written headline, and Watts went after the low-hanging fruit of showing that UHI exists in some places. I had no carrots today, so I'm grouchy. -
yocta at 14:11 PM on 2 February 2010The role of stratospheric water vapor in global warming
I think the author has removed the link for the actual text book as he says it is getting published, but you can still get to it by looking at the index directory from the site. (It is a public site so I am assuming that what I have done is copyright ok.) Go here: http://geosci.uchicago.edu/~rtp1/ClimateBook/ and open the file "ClimateVol1.pdf" -
Leo G at 13:24 PM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
Mr. Eater of Carrots (Love the name bytheway) - {It's funny that Watts chose to highlight Reno NV, without telling you that the USHCN's method removes the urban heating for that station. See Figure 8 in Menne, Williams and Vose (2009) BAMS, 90: 993-1007. Link was given above somewhere} The blog that jpark refered to was Anthony's response to desmogblog and another that had declared UHI a non-issue, as in the parrot skit - Dead! He shows where in peer reviewed papers the authors have corrected for UHI. Kinda like when a sceptic says that there is no basis for energy trapping from CO2, and John here, shows the absurdity of that claim. Nothing nefarious really. -
Marcus at 12:07 PM on 2 February 2010The role of stratospheric water vapor in global warming
Isn't it possible for SWV to travel from the upper to the lower stratosphere though John? Also, what might be the likely cause of the change in convection of water vapor from the troposphere?Response: "what might be the likely cause of the change in convection of water vapor"
This is all speculation, the paper doesn't go much into cause as their emphasis is on noting the change and calculating the effect. But it may have something to do with the temperature of the "cold point" which is the boundary where temperature stops falling with altitude and starts to rise. Eg - the tropopause, the boundary between the troposphere and stratosphere. A good discussion on possible mechanisms can be found at the Wunder Blog. -
Marcus at 11:43 AM on 2 February 2010The role of stratospheric water vapor in global warming
The other point, CoalGeologist, is that these blog sites conveniently ignore the obvious question-"where did the sudden rise in SWV come from"? The most obvious candidate is the oxidation of rising levels of anthropogenic methane-which still places the blame for global warming clearly in the lap of human activities.Response: I'm not so sure oxidation of methane is the obvious candidate. This occurs in the upper stratosphere while the change in water vapor has occured in the lower stratosphere just above the tropopause. This would point the finger more towards a change in the convection of water vapor from the troposphere. -
Marcus at 11:36 AM on 2 February 2010The role of stratospheric water vapor in global warming
Well, unless I'm totally wrong, Peter, isn't that the entire basis of Thermohaline circulation? Water warmed at the equator gets pushed towards the poles, then becomes increasingly saline as it cools down (& eventually freezes), pushing the warm water down into the depths & upwelling colder, less saline water from below-rinse & repeat. At least, that's how I always understood it. -
CoalGeologist at 11:28 AM on 2 February 2010The role of stratospheric water vapor in global warming
ChrisCanaris (#5): With respect, the terms 'contrarian' and 'denialist' that appear occasionally on this site are not "out of keeping with the spirit of genuine scientific enquiry". In fact, these terms are needed to distinguish genuine enquiry from disingenuous dogma. The term "denialism" refers not to skepticism, but to the presumption that AGW is wrong. This term would be gratuitous ONLY if used without justification. I would think skeptical scientists would want to erect a high wall between themselves and denialism. I will illustrate this with the following link, which offers a "Denialist" perspective on the significance of stratospheric H2O: http://www.theresilientearth.com/?q=content/its-water-vapor-stupid The article states: "These findings show that stratospheric water vapor represents an important driver of decadal global surface climate change, yet the IPCC crowd continues to focus on CO2." Cleverly written. The first part of the sentence is correct, but the second part is a non sequitur, implying there's no reason to continue to consider CO2 as a driver (three days after the paper was published!). Moreover, it's false. The lead author of the new study served as co-chair of IPCC Working Group 1 (2007) AR4 report. If there were an "IPCC Crowd", she'd be in it. In reality, this refers to the purported conspiracy to promote AGW. The blog states: "Here is a plausible explanation as to why the period from 1980 to 1999 was one of noticeable warming...", but according to the paper itself, this is false. The authors attributed ~30% of warming during the 1990s (sic) to stratospheric H2O, not 100%, as implied. (Gee, yesterday it was the sun!) Admittedly, 30% is a lot, and I agree we have much more to learn. In the meantime, I still need a term to describe an argument that presumes that CO2 plays an insignificant role, and then relies on deception to "prove" it. -
Eltanin at 11:22 AM on 2 February 2010Hockey stick is broken
I would consider moving the Climategate to its one argument. I believe this played much bigger in the media than you give it credit for. Maybe someting like.. Climategate clearly proves that AGW is a myth invented by scientists looking to make a quick buck... I wouldn't of thought to look here for information discussing that information.Response: Climategate already has its own page -
Charlie A at 11:20 AM on 2 February 2010The IPCC's 2035 prediction about Himalayan glaciers
SNRatio, what is also not very skeptical is failure to correct errors. I have been unable to get a reply to my inquiries direct to the author and the first co-author of the article. Not even a "hmmm, I'll look at it". Just total, complete silence. I guess I'll have to use the backup for peer reviewed science and send in a comment directly to GRL. I'll try once more with the authors, and then once via Byrd Polar Research Center. -
MattJ at 11:16 AM on 2 February 2010The role of stratospheric water vapor in global warming
Answering #24. I have seen that online textbook before, I thought it was promising, but how much longer will it still be under construction? The intro promises much, but it isn't there yet. Answering #21: it has been either strongly suspected or outright know for quite some time now, that _stratospheric_ water vapor is a greenhouse gas. That is why people are worried about contrails, and have already rejected the idea of using hydrogen to power jet planes. So the article was quite right to consider SWV most likely a cause of positive feedback -- which is exactly what we do not want. -
Berényi Péter at 10:48 AM on 2 February 2010The role of stratospheric water vapor in global warming
@19. chris at 06:38 AM on 2 February, 2010: chris, please, please explain how warmer and less saline water can replace denser cold & salty water at the bottom. I am really curious. -
Berényi Péter at 09:33 AM on 2 February 2010Lessons from the Monckton/Plimer debate
@84. chris at 06:11 AM on 2 February, 2010: This [TRMM satellite] has the obvious advantage (over your preferred Schumann resonance method) [...], that the spatial distribution of lightning can be determined" With at least three distant stations the spatial distribution of lightning activity can be determined as well by simultaneous monitoring of Schumann resonances. Even an amateur Schumann resonance monitoring network might be feasible, using the Internet, of course. Needs huge coils, ball antenna. All else is easy. Construction And Deployment Of An ULF Receiver For The Study Of Schumann Resonance In Iowa Anton Kruger http://www.ia.spacegrant.org/RES_INF/VRR2003/Kruger-SEED.pdf -
yocta at 09:30 AM on 2 February 2010The role of stratospheric water vapor in global warming
Thanks Turboblocke, i'm still learning. If anyone knows of a good text on weather and climate science they could recommend I'd be much obliged? :) I'm slowly rereading my old Sturman & Tapper book from undergraduate days but would like to hear of other ones out there...Response:All you could want and more is found in the online textbookPrinciples of Planetary Climate.UPDATE: my mistake, the book is no longer available online, now in press. Well, a good introduction to global warming, not as technical as Principles of Planetary Climate, is The Discover of Global Warming by Spencer Weart. -
Turboblocke at 09:02 AM on 2 February 2010The role of stratospheric water vapor in global warming
Yocta at 11. The change is about 10% of +/- 5ppmv of the stratospheric atmosphere. That isn't very much water in absolute terms, compared to the water in the troposphere. -
chris at 08:55 AM on 2 February 2010The role of stratospheric water vapor in global warming
I haven't read Solomon et al so I'm not going to make any specific comments. However at face value the paper (as paraphrased here) seems to be yet another reason to be concerned about the massive release of greenhouse gases. Right now there seems to be a number of contributions "piling up" that should be causing significant cooling: (i) 2003-2009 the sun has dropped to the bottom of the solar cycle (this should contribute around -0.1 oC of to the surface temperature over this period). (ii) 1980's to present: a slow (and rather small) negaitve trend in solar output (-0.05 oC?) (iii) Since around 1998; apparently the oceans have switched regimes to one with a cooling influence on the surface temperature (negative phase of the PDO). This might contribute around -0.1 oC relative to the long term ocean regime trend (which is zero). (iv) Stratospheric water vapour effect (see top article) which according to Solomon has reduced warming in the period 2000-2009 by 25% (so around -0.05 oC say). And yet 2009 was tied for the second warmest year on record. So if all of these contributions are real (and we are at least pretty confident about the solar cycle contribution)....they have been unable, colectively, to outweigh the warming contribution from enhanced greenhouse forcing... -
pedex at 08:27 AM on 2 February 2010It's Urban Heat Island effect
Furthermore as per the 3rd paragraph of the explanation laid out in this blog about UHI is patently false and anybody that has checked out the weather stations and locations in the US can easily see that. Their excuses do not jive with reality at all. Most NOAA stations do not even come close to meeting NOAA's own specs. This is why as part of the data set the terrain factors are included for each station as far as urban or rural and what kind of land they sit on. That way you can easily separate stations subject to urban warming from those that are not influenced by it.Response: I would suggest reading the paper I reference in the 3rd paragraph, Peterson 2003, and then explain the flaws in their methodology. Noone is denying that there are urban weather stations that are warmer than their rural neighbours - but statistical analysis shows there are almost an equal number that are situated in cool parks and show a cooler trend. Either way, urban stations are normalised to their rural neighbours to ensure there is no contamination of the temperature record. -
pedex at 08:22 AM on 2 February 2010It's Urban Heat Island effect
actually if you work with the adjusted data it isn't corrected for properly either, same problems show up this blog cherry picked an instance and claimed it was valid for everything and that's hardly the case at all which has already been demonstrated furthermore guys like Jim Hansen have already claimed single stations can and do reflect what is going on with complete continents or even globally which of course is false in its own right satellite data doesn't go back far enough to be of much use -
Doug Bostrom at 08:03 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
Riccardo at 02:57 AM on 2 February, 2010 "Here is my bet, they will focus on the raw data. " If you look at the data collection sheets provided for volunteers, you can see that there is little "data" beyond a photograph and geographic location information, which will never produce numerical results beyond what Menne did. The sheet includes space for anecdotal site information but coding that into some normalized form is going to be virtually impossible. If Watts had designed his survey better, he might have been able to produce something beyond Menne, but the information needed for that doing was not collected. I'm not even sure it would possible to do so; presumably adding prevailing winds at sites could help, getting some kind of quantitative readings of factors introducing errors, but in that latter case, how? Nobody can read Watts' mind, but I don't think he had a clear plan for what data he needed or for that matter even what he was trying to show, other than embarrassing photos. Who know, maybe there's something that can be done with all that effort. Hopefully. -
NewYorkJ at 07:58 AM on 2 February 2010The role of stratospheric water vapor in global warming
Some questions that the abstract doesn't seem to be clear on: Are the authors considering stratospheric water vapor a forcing or feedback, both, or can no conclusion be drawn? Since it doesn't determine the cause of the water vapor changes, it seems the conclusion would be one of the latter two. Could a conclusion from the study be that water vapor is a stronger positive feedback than previously estimated? It mentions stratospheric water vapor increased in the 90's and decreased in the early part of this decade. We also saw a leveling off of methane emissions, reduced solar activity, and a transition towards negative ENSO conditions. If any of these are a cause of the water vapor change, it seems to further support the positive feedback from water vapor. One thing that seems clear is that it might help improve mean climate model estimates at the decadal scale. 1990's warming exceeded the average climate model projection while 2000's warming generally is a little lower. Including the water vapor data seems likely to resolve model/observation discrepancies on short time-scales. -
Albatross at 07:44 AM on 2 February 2010The role of stratospheric water vapor in global warming
Peter re #21, I for one do not appreciate your unsubstantiated insinuations here. Drawing parallels between climate science and what happened in the financial sector is just wrong. Anyhow, this is a scientific debate about the Solomon paper and SWV, can we please stick to that? PS: Re OHC. The same "spike" ~2003 is also evident in 2003 in the global SST data (Smith et al. 2008, J. Climate, ERSST.v3b), Spencer looked into this and found that the spike in ERSST 3b was real. Can you provide proof that this spike is b/c of the Argo data, a published reference would help. I just perused the Smith et al. paper and there is no mention of the Argo data being included in their analysis. Anyhow, the *long term* trend of 0-700 m OHC is up, see also the papers that Chris provided. -
shawnhet at 07:09 AM on 2 February 2010Lessons from the Monckton/Plimer debate
Oops, sorry upon re-reading I appear to have had some poor phr in my last post(#83) that make what I was trying to say more than a lit obscure. from line 2 of the post "...that IMO there is also reason to believe that sensitivity is constant either" should read: that IMO there is also no requirement to believe that sensitivity is constant. 3rd papragrahp should read :From the above we can see that **while** changes in insolation due to orbital forcing are sometimes coincident with the temperature highs, not every high forcing situation leads to a high temperature regime. My apologies for any confusion. -
chris at 06:38 AM on 2 February 2010The role of stratospheric water vapor in global warming
re #20 Peter, there is certainly evidence that abyssal waters in the world's oceans may be warming (and deoxygenating), especially from Johnson's lab in Seattle (Pacific Marine Environmental Lab) [*] I suspect that considering the problems with the Argo floats, it's too early to say whether there is any discrepency between upper ocean heat content and expectations; after all we've only got a few years of Argo data. It's worth pointing out that the longish term (decadal; bi-decadal) accumulation of upper ocean heat is pretty close to model predictions up through 2008 [**] [*] Johnson GC et al. (2006) Recent western South Atlantic bottom water warming Geophys. Res. Lett. 33, L14614 Johnson GC et al. (2007) Recent bottom water warming in the Pacific Ocean J. Climate 20, 5365-5375 Johnson GC (2008) Warming and Freshening in the Abyssal Southeastern Indian Ocean J. Climate 21, 5351-5363 Ozaki H et al. (2009) Long-term bottom water warming in the north Ross Sea J. Oceanograph. 65, 235-244 Johnson GC et al. (2009) Deep Caribbean Sea warming Deep Sea Research. 1 Oceanograph. Res. 56, 827-834 Johnson GC (2008) Reduced Antarctic meridional overturning circulation reaches the North Atlantic Ocean Geophys. Res. Lett. 35, L22601 [**] S. Levitus et al. (2009) Global ocean heat content 1955-2008 in light of recently revealed instrumentation problems Geophys. Res. Lett. 36, L07608 -
Prasad Kasibhatla at 06:27 AM on 2 February 2010The role of stratospheric water vapor in global warming
I posted this comment on RealClimate - thought I'd post it here as well to see if anyone here has any insights: Re the contribution of the post-2000 decrease in stratospheric water vapor contributing to the ‘flattening’ of the global warming trend – I am struck by the dissimilarity between the observed and modeled temperature curves post-2000 in Figure 3b. It looks like the model’s response it to simply adjust (almost instantaneously) to the drop in water vapor in 2001, and I see no evidence of a ‘flattening’ of the trend. Am I missing something? -
Berényi Péter at 06:12 AM on 2 February 2010The role of stratospheric water vapor in global warming
Alabatross, there is a step like increase in NOAA OHC time series in 2003. That much is true. However, it was the year Argo floats were deployed en masse. That is, the measurement system changed radically at that time. It's got much better, at least down to 1000 m, perhaps. It was supposed to do measurements down to 2000 m, but due to instrumental problems that has not worked until recently. No warming detected since then in the upper 700 m, a level well below the thermocline. There is some speculation that heat went to the abyss, but water down there being about as cold and salty as it can get, it is not easy to figure, how substantially warmer water could slip there. -
chris at 06:11 AM on 2 February 2010Lessons from the Monckton/Plimer debate
Peter, it seems unfair to cite a set of scientists in support of a poorly-characterized theory, and then to call them names ("reality-denialist"?!) when their papers turn out not to agree with your notions. According to recent work by Price (who you have cited in relation to Schumann resonance), what you consider to be obvious, isn't actually obvious at all. The question of how lightning activity responds in a warming world isn't straightforward (see Price's recent paper [*] and abstract below [**]. Likewise, whereas you consider Schumann resonance a means of determining global lightning activity, Price prefers to determine global lightning activity from The Tropical Rain Measuring Mission (TRMM) satellite. This has the obvious advantage (over your preferred Schumann resonance method) [which Price uses to analyze possible lightning/upper tropospheric water vapour variability (see my post #58 and #63)], that the spatial distribution of lightning can be determined and correlated with local phenomena. In fact Price concludes [as does Pinto and Pinto (see my post #58)] that lightning activity seems to be consistent with predictions from climate models. I would have thought that if the scientists who's work you cite don't actually agree with your notions, that it might be worth considering whether your notions have merit. [*] Price C (2009) Will a drier climate result in more lightning? Atmos. Res. 91, 479-484 [**]With recent projections of a warmer climate in the future, one of the key questions is related to the impact of global warming on thunderstorms, and severe weather. Will lightning activity increase in a warmer world? Since the majority of global lightning activity occurs in the tropics, changes in future global lightning activity will depend on changes in the tropical climate. The latest IPCC [Intergovernmental Panel on Climate Change (IPCC). 2007] projections show a partial drying out of the tropical landmasses as the global climate getswarmer. This is caused by both changes in rainfall patterns, but also due to increases in evapo-transpiration. We would expect a drier climate to produce fewer thunderstorms, and less lightning. However, experimental and modeling studies have shown that as tropical regions dry in the present climate, they experience greater lightning activity. This paradox may be explained by noting that while drier climate conditions result in fewer thunderstorms and less rainfall, the thunderstorms that do occur are more explosive, resulting in more lightning activity.
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shawnhet at 06:06 AM on 2 February 2010Lessons from the Monckton/Plimer debate
#77, GFW since the issue of sensitivity is the core of the warming debate, let me just say that IMO there is also reason to believe that sensitivity is constant either(rather than debate sensitivity vs. forcing in detail). I don't know the particulars of Monckton's or Plimer's position, so I don't know their specific position In re: Milankovitch cycles, while it is of course true that insolation changes due orbital shifts have an effect, things are a lot more complicated than a simple constant response to forcing would imply. http://en.wikipedia.org/wiki/File:Vostok_420ky_4curves_insolation.jpg From the above we can see that changes insolation due to orbital forcing are sometimes coincident with the temperature highs, not every high forcing situation leads to a high temperature regime. This situation allows a wide variety of possible explanations to be feasible, but does not seem consistent with a simple linear relationship btw forcing and resultant temperature change. Cheers, :) -
Albatross at 05:28 AM on 2 February 2010The role of stratospheric water vapor in global warming
Arno @16, please cite some reputable and published references to back up your assertions. 0-700 m OHC actually increased significantly circa 2003, a time when there were no super El Nino: http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/ Also, this is what the global surface-air temperatures have been doing: http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.lrg.gif And global tropospheric temperatures: http://www.remss.com/msu/msu_data_description.html#msu_amsu_trend_map_tlt (Look at Fig. 7 Ch TLT) Have you been reading Bob Tisdale's page perhaps? -
Berényi Péter at 04:41 AM on 2 February 2010Lessons from the Monckton/Plimer debate
@59. Tom Dayton at 10:05 AM on 31 January, 2010 Tom, you don't need a monitoring network to track global lightning activity. It can be done from a single spot with rather inexpensive equipment. Schumann resonance measurements started for example at Nagycenk, Hungary in early 1960s, automatic digital data collection was installed in 1993 and is performed since then. Your reference to wiki "A strong link between global lightning and global temperature has not been experimentally confirmed as of 2008" referes to the fact that global lightning activity has not increased while global average surface temperature was supposed to go up. Strong local positive correlation between surface temperature and lightning is firmly established, lower troposphere moistening (below 850 hPa) is also well documented. It is an enigma, no matter how much mainstream reality-denialist effort is spent on it. -
Berényi Péter at 04:08 AM on 2 February 2010The role of stratospheric water vapor in global warming
Any idea where the extra water vapor went from the lower stratosphere in 2000? -
carrot eater at 03:19 AM on 2 February 2010The role of stratospheric water vapor in global warming
How well mixed is stratospheric water? Can the Boulder weather balloon readings be taken as representative? Water content is sensitive to temperature. Though I do see the Boulder readings are consistent with the satellites. -
Riccardo at 02:57 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
jpark, hint: look at fig.7 of the paper quoted by carrot eater. I'm waiting for a Pielke and Watt paper on this, for years indeed, so hopefully this story will come to an end and archived for ever (just a hope, isn't it?). Judging from their blog posts it won't add much to the subject. Here is my bet, they will focus on the raw data. -
carrot eater at 02:33 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
jpark: There was no cherry picking in only using 40%. They used the 40% that was publicly available on Watt's website, and then had their own people confirm most of those ratings. They then considered whether there were enough stations in enough places to do an analysis, and they found that they did. If the stations are well-distributed, you don't need a high number of stations to compute a national average. Menne has previously published an analysis discussing how many stations you need to get an accurate idea of the overall picture. See Vose, Menne (2004), Journal of Climate 17: 2961-2971. Adding more stations would help, though you eventually reach a point where adding more stations doesn't change anything. -
carrot eater at 02:24 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
jpark: You can see the result of the homogenisation for Reno yourself, in the paper I cited. A huge warming trend is significantly reduced. Where some sceptics get confused is that they think UHI is the only thing you'd ever need to adjust for, and then they get angry when they see any upwards adjustments. However, other things can require either upwards or downwards adjustments, and in the US, changes in the time of observation stand out as a requiring upwards adjustments. One thing to not forget is the US CRN network, which is entirely sited to avoid any of these problems. It's newish, but it's been up for a few years now. After adjustments, Menne (2010) showed that even the 'poor' stations matched the US CRN. That would tell you that they're doing something right. -
jpark at 02:02 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
Carrot eater - v helpful. So the temperatures are adjusted down to counteract the UHI, yes? -
jpark at 01:59 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
Thanks Ricardo - lets see if they do the analysis then. Pity Menne only used 40% of the available data tho. Bit like only using some bristlecones, like a D'Arrigo cherry picked pie. Pielke says "We will discuss the science of the analysis in a subsequent post and a paper which is being prepared for submission." so it looks like it is happening... -
carrot eater at 01:55 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
jpark, this is tosh. Anybody knows there are individual stations out there that show urban heating. You don't need Watts for that; you can see it from the people who actually do published work. The question is whether those effects are contaminating the overall surface record, and by any actual analysis, they appear to not do so. It's funny that Watts chose to highlight Reno NV, without telling you that the USHCN's method removes the urban heating for that station. See Figure 8 in Menne, Williams and Vose (2009) BAMS, 90: 993-1007. Link was given above somewhere. -
Riccardo at 01:12 AM on 2 February 2010On the reliability of the U.S. Surface Temperature Record
come on jpark, you know very well that when the data are homogenized ("adjusted") people (sceptics) screams out loud. This is the very reason why they show raw data only. We all know that UHI exists and indeed, before being considered for the average of their respective grid point data are corrected for UHI effect, station movement, instrument change, etc. I've never (NEVER) seen Watt do the full analysis. Given that behind Watt there is Roger Pielke Sr., they sure have the skill to do it. If they don't, the reason is clear. That post is just a confirmation that what they say is irrelevant.
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