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Arkadiusz Semczyszak at 19:02 PM on 28 June 2010Ocean acidification
@VoxRat "... a century or two ...” - you must compared with: “... a rapid recovery of coral reefs in areas of Indonesia, following the tsunami ... [2004 -2009]” As was the myth about the current rapid growth of abnormal pH, I recommend: http://omniclimate.wordpress.com/2009/02/04/a-shell-game-behind-ocean-acidification/ -
tobyjoyce at 18:37 PM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
Excellent Professor David Barber lecture on the current state of the Arctic Ice. Forward the video to 12:00 to skip the intros. Dr. David Barber -
John Bruno at 17:53 PM on 28 June 2010Perth event tonight: public forum on climate change
wonderful. wish I could be there. thanks to whomever organized this. -
omnologos at 17:12 PM on 28 June 2010How many climate scientists are climate skeptics?
doug_bostrom (#120): Revkin writes "For starters, one aspect of such efforts that I find troubling is the definition of categories...". And that's "for starters" 8-) In one of the comments at DotEarth, Revkin also links to Weart's comment #12 in this thread. Have a look. Finally, Revkin points to Keith Kloor's blog, that opens with "Judith Curry identifies what she considers to be “the big flaw” in the PNAS paper". And what have you been reading at RealClimate? How about this: "we note that once the categorization goes beyond a self-declared policy position, one is on very thin ice because the danger of ‘guilt by association’. For instance, one of us (Eric) feels more strongly that some of Prall’s classifications in his dataset cross a line" I say, even the guys at RealClimate could see the "methodological issues" with the PNAS paper, and felt free to talk openly about those. Where's instead the evidence that, in this circumstance, Skeptical Science has not "credulously pushed any news that might further its case"? -
JMurphy at 17:08 PM on 28 June 2010Why does Anthony Watts drive an electric car?
philc wrote : "Thanks y'all for turning a marginal, but attractive(I hate bills) investment into one that is delivering around 6.5% and rising for the next 20 years." And yet the so-called skeptics reckon we are going to have to go back to the Stone Age and wear sack-cloths if we want to do anything to restrict the use of Carbon ? What you called the 'great AGW scare' seems more like the great AGW benefit (a benefit to alleviate a problem) to me. A great advertisement for doing the right thing : well done. -
Doug Bostrom at 12:48 PM on 28 June 2010Why does Anthony Watts drive an electric car?
Philc, if you've not done it already, be sure to check on solar domestic hot water. Great bang for the buck. Works for me here in Seattle, worst-case scenario second only to Anchorage for U.S. cities and appears set to pay for itself before my 13 year old graduates from college even though I did not bother with any taxation juju. For some reason, here in the U.S. this is a big surprise... -
CBW at 12:40 PM on 28 June 2010What causes the tropospheric hot spot?
It is interesting that the skeptics are so eager to misinterpret Figure 1 that they miss the real GHG signal that it clearly identifies--tropospheric warming combined with stratospheric cooling--which none of the other forcings could possibly produce.* How do they explain the fact that exactly that signature has been observed? *Except, in the figure, ozone, which I've been under the impression *is* a GHG. -
johnd at 10:46 AM on 28 June 2010What causes the tropospheric hot spot?
carrot eater at 10:25 AM, it was along the various longitudes I meant. Both the models and the observations should vary somewhat given the different surface conditions and hence perhaps give better understanding to what is expected, and what does or does not actually occur. As for the latitude cross section, I would have thought that there would have been some bias in the model given the quite significant difference in the observed northern and southern hemisphere temperatures. -
philc at 10:39 AM on 28 June 2010Why does Anthony Watts drive an electric car?
I'm a bit of a skeptic, but that didn't stop me from installing a 5.6 kw solar panel array. Mainly it seemed like a pretty bullet proof investment given the great likelihood of ongoing increases in electricity rates, and I hate bills. But thanks to the great AGW scare it suddenly became an even better investment when the guvmint decided to subsidize its installation and allow me to roughly double the rate of return by selling renewable energy credits. Thanks y'all for turning a marginal, but attractive(I hate bills) investment into one that is delivering around 6.5% and rising for the next 20 years. -
carrot eater at 10:25 AM on 28 June 2010What causes the tropospheric hot spot?
19, johnd The figures above are model results, not observation, but the x-axes are latitude, which is what you seem to want. For observation, there are different sources; the last article here linked to one that has charts broken down by NH, tropics, SH. http://camels.metoffice.gov.uk/quarc/Sherwood08_JClimate.pdf -
Bern at 10:12 AM on 28 June 2010What causes the tropospheric hot spot?
papertiger @ 18: Who's refusing to understand it's importance? That is, after all, the entire point of the post. Short term variability often masks subtle long-term shifts, and this hot spot is no different. Look at this post for an example of the effect, where annual variation in CO2 levels is quite large, although over longer periods the rising trend dominates. I get the impression that you regard a long-term shift to be insignificant if it's less than the short-term variability in the system? If so, then I'm sure you wont mind terribly if the average temperature in your neighbourhood increases by 10ºC or so, as that's still less than daily variability... -
johnd at 09:39 AM on 28 June 2010What causes the tropospheric hot spot?
The depiction of the hot spot I assume is the average of data collected around the full circumference of the globe. Is there any depiction of how the hot spot varies, or should vary across the various regions of vastly different surface conditions? -
Doug Bostrom at 08:58 AM on 28 June 2010IPCC were wrong about Amazon rainforests
OT but I should add, where I live "we" are the government and are too ignorant and shortsighted to run our affairs properly and meanwhile "we" tell businesses what they should sell us by buying their products. The hysterical whining and finger-poiting over the BP cost-cutting fiasco here makes me puke; we're the people insisting they sell us oil, we're the people who are too complacent to get educated, to vote. Talk about "look in the mirror." Ridiculous. -
Doug Bostrom at 08:52 AM on 28 June 2010IPCC were wrong about Amazon rainforests
BP it seems we're in rare conjunction on the insult being delivered to the Amazon forest region. And I agree, the philosophy of biofuels is substantially porous in all directions. Where we diverge is the point of th IPCC report, which calls our attention to another folly on a massive scale, also laid at the feet of anachronisms. A scare? No more so than if I were to drop an anchor off the side of a boat with my feet standing in a loop of anchor chain and then, knowing this, not hop aside. More scary drowning that not. I've almost drowned twice, it was upsetting but the long-lasting regret has been reviewing how I put myself in the position of confronting breathing water when a little common sense would have made the exercise unnecessary. -
Berényi Péter at 08:20 AM on 28 June 2010IPCC were wrong about Amazon rainforests
#19 doug_bostrom at 07:07 AM on 28 June, 2010 We're already the equivalent of an existentially threatening disaster In Amazonica, yes. Not "we", neither "the people", but irresponsible government and business practices. Including the biofuel craziness promoted by the AGW scare. The bottom line is that neither AGW nor CO2 has anything to do with the ongoing deforestation in the Amazon basin, therefore including it in the IPCC report has no point other than to provide some absolution for those who need it. It is imperative to keep in touch with reality. the encyclopedia of the earth Deforestation in Amazonia Lead Author: Philip M. Fearnside Last Updated: March 30, 2007 See also:
Terra Preta de Indio by Johannes Lehmann
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johnd at 08:12 AM on 28 June 2010IPCC were wrong about Amazon rainforests
Berényi Péter at 07:00 AM, thanks for posting the link to the Acta Amazonica paper, I found it very interesting, not only for the subject under discussion, but how it relates to events in other parts of the world. Firstly, in Australia the years 1925 to 1930 saw widespread drought and below average rains across much of Australia, as did the years 1911 to 1916. In fact dry conditions across much of Australia were a fact of life for the entire first half of the 1900's with wetter conditions becoming more frequent post WW2. Anecdotal evidence is that the 1800's were also more prone to below average rains and droughts similar to the early 1900's. Secondly, the reference to the three prominent 'chimney' regions of convective upwelling, South America, Africa and the Maritime Continent is also of interest. Research in recent years has identified the IOD, the Indian Ocean Dipole, and this ties together the weather and climatic conditions of all those regions bounding the IO, Africa, India, Indonesia and Australia. It appears the the IOD has it's own cycles that at times, at least for Australia, either complements or offsets some of the ENSO effects. Droughts in Indonesia seem to correlate with droughts in Australia, with the major recent forest fires in Indonesia, 1982 and 1998 coinciding with dry conditions over much of Australia as well as those other dry periods in the Amazon basin as indicated by you. However, having said that, there is more often than not drought conditions somewhere in Australia, and perhaps the same might apply to other large areas such as South America and Africa. -
scaddenp at 07:59 AM on 28 June 2010Astronomical cycles
philc - I dont believe you understand how parameterisation is done in GCMs. faq II for even more detail. In particular, I object that the "adjustable parameters" in GCM can be tuned in the way you say. Lets say that I use fundamental physics to create full model of process. It can be used over entire range of observable data. However, it might be also impossible to use in full form from computation limits in GCM or because if scale. You can however replace with parameterized model that is easy to calculate but which you can nonetheless verify works over full range. I suggest further discussion goes in "are models reliable" rather than here.Moderator Response: scaddenp's suggestion that further discussion happen on the Models are unreliable thread is a good one. So please do. -
Doug Bostrom at 07:36 AM on 28 June 2010IPCC were wrong about Amazon rainforests
When the IPCC relies, as it has done far too often, on WWF and Greenpeace propaganda pieces, and newspaper articles, and the like... Willis if you quantify that assertion you'll be moving closer to joining the realist school of critique, moving away from applying your brush to impressionist strokes like that one. What are the statistics? If this were trivial as you claim ... then why does it get its own page on this very site? Good question. Why have journalists following Paris Hilton caused forests of pulp trees to fall when she's unarguably so inconsequential? The topic of the Amazon non-scandal appears here because all the overblown hype on this issue has left the public confused about what actual relevance this story had, which turns out to be little indeed. Finally, in addition to the IPCC question, the science is at issue as well. I have yet to see anyone link to a peer-reviewed article showing any evidence that 40% of the Amazon is at risk due to reduced rainfall due to warming ... Thank you for affording me the opportunity once again to quote the authority on the subject, Nepstad, whose work this vapid brouhaha was all about: In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement. Senior Scientist Daniel Nepstad endorses the correctness of the IPCC’s (AR4) statement on Amazon forest susceptibility to rainfall reduction ...particularly when the Amazonian rainfall has not reduced during the last century of overall warming. As you well know even though you are sitting behind the easel of an impressionist, the subject whose portrait you are interpreting did not refer to past times. Here's what the subject did say: Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation; this means that the tropical vegetation, hydrology and climate system in South America could change very rapidly to another steady state, not necessarily producing gradual changes between the current and the future situation. -
philc at 07:35 AM on 28 June 2010Astronomical cycles
Skeptical Science-Scafetta Enough already. It's elementary math and statistics that fitting a function to the data is only valid for the extent of the data. The fitted curve cannot be used to extrapolate future values. A good example are some of the IPCC graphs attempting to estimate future values of the temperature, depending on various emissions scenarios. In order to fit the 'curve" some of the emissions scenarios imply that temperatures in the past would be a hundred or more degrees below 0. For scientific usage, fitting a curve might show that the data has some periodic function in it, prompting a search for possible mechanisms, or it might give some insight into possible mechanisms to investigate. That, despite some of the exaggerated claims, is the whole point of the Scaffeta paper. There are apparent periodicities in the temperature data which coincide with periodicities in various solar, lunar, and planetary orbits. That suggests there might be a causative relationship that should be investigated. Very similar to the idea that rising C02 levels, even though they follow the intial temperature rise, correlate to rising temperatures in a fashion and might be part of the cause of rising temperatures, rather than an effect of them. the same thinking applies to any paramaterized model(all the GCM models in use). As pointed out by many others, any model with adjustable parameters in it is one person's opinion about what is going on. It may be useful in suggesting areas for further study and data gathering, it may suggest further experiments, but the model itself is useless for prediction outside the range of data used to calibrate it. For a good example of a non-parametric model look into the photo electric effect. A nice, simple equation, from first principles, that gives valid results over a wide range. -
Willis Eschenbach at 07:19 AM on 28 June 2010IPCC were wrong about Amazon rainforests
doug_bostrom at 23:39 PM on 27 June, 2010 >> ...Despite all your unusually pragmatic work at WUWT, here you are regressed to grinding on IPCC process minutia of no actual significance. >> Doug, thanks for your thoughts. This is not "process minutia". When the IPCC relies, as it has done far too often, on WWF and Greenpeace propaganda pieces, and newspaper articles, and the like, it shows that the IPCC is a political rather than a scientific organization. Since many people claim that "the science is in" and "the IPCC has spoken, no one can dissent" and the like, this is very important. If this were trivial as you claim ... then why does it get its own page on this very site? Finally, in addition to the IPCC question, the science is at issue as well. I have yet to see anyone link to a peer-reviewed article showing any evidence that 40% of the Amazon is at risk due to reduced rainfall due to warming ... particularly when the Amazonian rainfall has not reduced during the last century of overall warming. -
Doug Bostrom at 07:07 AM on 28 June 2010IPCC were wrong about Amazon rainforests
Yeah, looking at the graph again was a nice example of "confirmation bias," I suppose. Once I looked at the rest of it I see routine boom and bust. Apparently there's concern that the forest's resiliency has been degraded due to thoughtless treatment by various people trying to scrape out a living in the region, also to keep the flow of hamburgers steady. GScholar "Amazon deforestation" for details. We're already the equivalent of an existentially threatening disaster. -
Berényi Péter at 07:00 AM on 28 June 2010IPCC were wrong about Amazon rainforests
#16 doug_bostrom at 05:04 AM on 28 June, 2010 the 1998 drought appears to be visible in your graphs Somewhat. Assigned to 1997 by the method I have applied. 1992 appears to be worse. However, if you are interested in how a really severe drought looks like there, read this paper: Acta Amazonica Print version ISSN 0044-5967 Acta Amaz. vol.35 no.2 Manaus April/June 2005 doi: 10.1590/S0044-59672005000200013 The drought of the century in the Amazon Basin: an analysis of the regional variation of rainfall in South America in 1926 Williams at al.
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Doug Bostrom at 06:55 AM on 28 June 2010Accelerating ice loss from Antarctica and Greenland
More on the Pine Island robot mission here, with plentiful nits to pick at. Here are more details of the robot itself and its operations. 5,000(!) D-size batteries sounds on the face of it a questionable choice for power but I suppose grad students had to do the changing. The sub was capable of fully autonomous operation tens of kilometers from the mother ship and -under- the ice. Truly remarkable. -
johnd at 06:54 AM on 28 June 2010IPCC were wrong about Amazon rainforests
Berényi Péter at 04:43 AM, the precipitation graph doesn't seem to indicate any exceptional deviations that could account for 2 specific events mentioned in the lead post, namely "severely drought stressed in 1998" and "the intense 2005 drought". Would it be the definition of "drought"? In tropical areas a drought could be 3 months without significant rain which disappears in the records when the followup rains return the annual precipitation to near normal levels. Or would it be that the drought conditions were localised to certain parts of the basin? How much variation was there across all of the cells, and was there any groupings of cells that were significantly different to the overall average? -
Doug Bostrom at 06:06 AM on 28 June 2010Accelerating ice loss from Antarctica and Greenland
Péter, lighten up. Discussion on this site routinely slews over eons, take "recent" for what you will. -
Riccardo at 06:02 AM on 28 June 2010Accelerating ice loss from Antarctica and Greenland
You're right Berényi Péter, this adds a lot to the sensitivity of (at least) this glacier to climate change. -
Riccardo at 05:56 AM on 28 June 2010Accelerating ice loss from Antarctica and Greenland
Doug, thanks for alerting us on this paper. It's really a strong confirmation on the role of the grounding line retreat on ice sheet dynamics. It's good news that piece by piece the puzzles is becoming clearer, but bad news that we now know that it won't be easy to stop or even slow down this and similar glaciers. -
Berényi Péter at 05:49 AM on 28 June 2010Accelerating ice loss from Antarctica and Greenland
#19 doug_bostrom at 03:58 AM on 28 June, 2010 why this glacier has been on a speedy wasting trajectory in recent time You fail to mention "recent time" here started more than forty years ago, when global temperatures happened to be on a falling trajectory for a while. NASA Earth Observatory news release, June 20, 2010 New Research Sheds Light on Antarctica's Melting Pine Island Glacier Lead author Dr Adrian Jenkins of British Antarctic Survey said, [...] "We do not know what kick-started the initial retreat from the ridge, but we do know that it started some time prior to 1970" -
papertiger at 05:35 AM on 28 June 2010What causes the tropospheric hot spot?
You're talking about the hot spot that isn't there right? It's hard when the short-term variability is nearly an order of magnitude greater than the long-term trend. That's a keeper! Thank you for stating the obvious, even while stubbornly refusing to understand it's importance. -
Doug Bostrom at 05:04 AM on 28 June 2010IPCC were wrong about Amazon rainforests
Great work, BP, but the topic here is what's been learned from past interannual drought, experimentally created drought (Nepstad 2004: Mortality of Large Trees and Lianas Following Experimental Drought in an Amazon Forest), expectations of what those lessons foretell. BTW, cool that the 1998 drought appears to be visible in your graphs. -
Berényi Péter at 04:43 AM on 28 June 2010IPCC were wrong about Amazon rainforests
What are we talking about? Precipitation is hardly decreasing in Amazonia, at least not since 1920.
I have downloaded v2.prcp.Z from the GHCN v2 ftp server.
Then selected GHCN stations in Amazonia, in the rectangular region between 50°30'W - 74°30'W and 3°N - 13°S. This 24°×16° rectangle covers Amazonia pretty well (spherical distortion is negligible close to the equator).
There are 284 GHCN stations there, geographical distribution looks like this:
I have calculated average monthly precipitation for each 1°×1° cell where data were available. Then using these values average was obtained for 2°×2° cells, and so on up to 8°×8°. There are 6 such cells in the region, their average is the monthly signal for Amazonia. From this, one can get annual precipitation sums. I have chosen to sum up June-May data and assigned it to the starting year. This way I could use all the data available up to May 2010 (and didn't have to cut wet seasons in half).
The procedure followed is meant to compensate for possible uneven distribution of GHCN stations.
There is one caveat. In 1997 coverage of the region in GHCN started to deteriorate rapidly. Until 2003 stations are only getting sparse, but overall coverage is preserved more or less. After that even this is not enirely true.
To see the possible effect of gradual station dropout I show you the entire record between 1892-2009.
Data before 1920 are clearly unusable. If Amazonia would have been that dry, it must have been an epic event. The problem is station distribution prior to 1920 is not representative at all. People do not like too much rain, so they started to settle in drier parts of the region.
It is a bit better with recent station dropout, because it is not based on preferences of settlers, but on God-knows-what, probably unrelated to rain.
However, considering the central role GHCN plays in climate science and in all those expensive policy decisions based on it, the reckless way this database is handled is stunning.
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Doug Bostrom at 03:58 AM on 28 June 2010Accelerating ice loss from Antarctica and Greenland
Neat little example of a model confirmed by a robotic mission, both exploring Pine Island glacier in Antarctica and both tasked with helping to explain why this glacier has been on a speedy wasting trajectory in recent times. The discovery of an underwater mountain ridge could help solve the mystery of why Antarctica's Pine Island glacier is vanishing so rapidly. A robot submarine sent beneath the glacier's floating ice sheet has shown that there is a ridge rising 400 metres from the sea floor. Until recently, the glacier would have rested on this ridge, preventing warm seawater from reaching the ice and melting it from underneath. But the submarine has shown that the glacier no longer rests on the ridge - it has thinned and now floats above it (Nature Geoscience, DOI: 10.1038/ngeo890). ... In January, a modelling study suggested that if such a ridge did exist, then once the glacier retreated behind it, the glacier would not be able to recover. Ice shelf was kept intact by underwater ridge (New Scientist) -
David Grocott at 03:04 AM on 28 June 2010What causes the tropospheric hot spot?
I think it's important to note that in Nova's 'Skeptic's Handbook' she is clearly of the belief that the tropospheric hot spot is a signature specific to AGW; she refers to "the telltale “hot spot” warming pattern that greenhouse gases would leave". John, in his initial post, pointed out that this was incorrect, stating "we expect to see an amplified warming trend in the troposphere no matter what’s causing the warming". As a result of John's correction, Nova seems to have changed her position, and in her recent article in response to John's post wrote:...strictly any form of warming ought to increase evaporation, increase humidity, and in the world of climate models, raise the level of warming 10 km up over the tropics (ie, create a hot spot).
I think the fact that Nova has admitted her mistake on this is important. It's not just about semantics. If the hot spot was just a signature of AGW, then those arguing that it is absent would have an easier task. They could say, "yes there is warming, but the lack of a hot spot proves it is not humans". The fact that the hot spot acts as signature for warming from any source means that if people want to argue it is absent, they now have to say "no there is no warming, as demonstrated by the absence of the tropospheric hot spot". This would be a difficult argument to make considering all measurements show a warming trend. -
Doug Bostrom at 02:58 AM on 28 June 2010Abraham reply to Monckton
Another professor examines Monckton's work and finds it wanting. Detailed dissection here: The Monckton Files: Solar Variation
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Doug Bostrom at 02:38 AM on 28 June 2010What causes the tropospheric hot spot?
I read Nova's bit carefully and I note that she can produce a reasonable explanation of why a "hot spot" will exist, actually an explanation that worked well for me. She does not dispute that the phenomenon really must exist. Yet she refuses to acknowledge that failure to see the hotspot by instruments is a fundamental problem and that comparisons w/model predictions can't be made until the instrumentation issue is resolved. More rhetorical impressionism. I'm close to settling on the term "impressionist" for a fairly major swath of Nova-type persons. Prestidigitation is another possibility but it over-describes. -
Albatross at 02:21 AM on 28 June 2010What causes the tropospheric hot spot?
Robhon @13, I would like to echo your thoughts. The vitriol and invective in Ms. Nova's missive is both unacceptable and unprofessional, and only goes to undermine whatever credibility she thinks she might have on this issue. -
CBW at 02:20 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
D'oh, never mind my questions in #66. Neven's site has a link that shows some history. The answer is that it varies a lot year to year (big surprise in the arctic), and those yellow things are, indeed, buoys. Doug, I agree, it's amazing what cheap technology allows you to do. Have a look at the pictures in the link, above. Fascinating stuff. The only problem is that when it gets really interesting, the camera tends to die. -
Albatross at 02:18 AM on 28 June 2010What causes the tropospheric hot spot?
Ms. Nova continues be “mistakenly thinking the tropospheric hot spot is a signature of the greenhouse effect” There is so much wrong with her aggressive attack on this point. Is she denying that the greenhouse effect exists based on this misunderstanding? The greenhouse effect was around before we humans started emitting GHGs. That there is a “greenhouse effect” is very well established and not disputed, even by reasonable “skeptics”. Or is her misunderstanding of the science leading her to erroneously argue that we are not experiencing an enhanced greenhouse effect on account of higher concentrations of GHGs from human activities? Or is she concerned that the TROPICAL “hot spot” is not as strong as predicted by some models? The biosphere has been experiencing an enhanced greenhouse effect for decades now. How that manifests itself has been clearly documented by long term trends in multiple, independent observations. For example, long term warming in the SAT record, long term cooling of the lower stratosphere, long term increase in OHC (see Murphy et al. 2009 and others), and an increase in the height of the tropopause (Santer 2003) as evidenced by radiosonde data. IMO, Nova is being disingenuous with here musings on this topic and seems to be doing here best to obfuscate. That is evidenced by the lack of caveats in her musings as to the limitations of both the models and the observations—she seems to be naïve about the real-world complications of working with radiosonde (different sensors and platforms, sensor changes, sparse coverage etc.) data and MSU data. I also find it intriguing that she seems to claim to know more about this complex field than experts such as Santer et al. She should also read the README file for the UAH data sometime and see for herself the multitude of errors, corrections and other issues with that particular product. I take issue with the first graph that she presents in her latest post. First, the graph on the right panel is labeled “no hot spot” when in fact, there is warming, it is just not as significant as that predicted. The discrepancy between the models and the observations is complex. Partly b/c the maximum warming is predicted to occur near the tropopause, a region not sampled well by MSU products such as RSS b/c of “contamination” from the stratosphere—Ms. Nova does not seem to understand that the satellites do not directly measure temperature but radiances from relatively deep/coarse layers in the atmosphere-- a frustrating problem when one is trying to make measurements near regions of sharp temperature gradients such as between the troposphere and lower stratosphere (region where “hot spot” is expected to be a maximum. Not to mention the fact that the troposphere is warming while the lower stratosphere is cooling, so that further complicates trying to extract meaningful long-tern trends. The UW adjusted RSS product (which address the “contamination” issue) finds that, globally, the mid-troposphere has been warming of +0.15 K/decade since 1979 (from NCDC, annual temperatures up to and including 2009). On the model side, the AOGCMs do have issues with handling moist convection (i.e., thunderstorms), primarily because their horizontal grid spacing is too coarse. Consequently, they may be being too aggressive in their tropospheric warming over the tropics where convection predominates. IMHO, at most, this is a debate as to much to do with the limitations of the AOGCMs simulate convection and complex issues associated with accurately sampling and resolving temperature changes the upper-troposphere. The observed discrepancies have nothing whatsoever to do with whether or not the greenhouse effect is real, or whether or not we are experiencing an enhanced greenhouse effect. There are more appropriate and reliable measures which support the existence of an enhanced greenhouse effect. As far as I can tell, Ms. Nova’s beloved “missing hot spot” also has nothing to do with global equilibrium climate sensitivity. -
Doug Bostrom at 02:14 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
How amazing and marvelous that we're able to drop remote sensing equipment like that at the N. Pole. Little chance of theft, either. Years ago I was involved with a project to attach radio-equipped digital imagers to outdoor analog instruments, reporting to data concentrator boxes. One of our camera gizmos was stolen but managed to send a final picture before going out of range, showing the interior of a pickup truck bed. No mug shot of the perp, unfortunately. -
Rob Honeycutt at 02:12 AM on 28 June 2010What causes the tropospheric hot spot?
I have to say to John, bravo for keeping above the fray. Again, reading the tone of both the article and the discussion on JoNova's site is rather alarming. It really does little to address the scientific issues regarding climate change when people stoop to such personal attacks. I'd like to better understand why Nova and her cohorts reject this stuff and where they're getting their information. I honestly would. But I stop reading when it gets personal. I also have to thank those who post on this site with their perspectives that reject AGW for maintaining a sense of decorum. It makes a huge difference. I'm sure you often feel outnumbered here but I hope that you feel you get a fair hearing. If you ask me, that is what skepticism is all about. A fair hearing from all sides. -
carrot eater at 02:06 AM on 28 June 2010What causes the tropospheric hot spot?
RickG: It ends up being a negative feedback, in a way that is perhaps not obvious. For the greenhouse effect to work, there has to be a lapse rate. The emission that makes it back out to space needs to be from a colder place than the surface. But due to this 'hot spot' effect, the lapse rate is reduced. So the greenhouse effect becomes less powerful than it otherwise would have been. But there's also a positive feedback in the story, as the increased atmospheric moisture that causes the 'hot spot' itself causes a major positive feedback, as water vapor is a greenhouse gas. So in short: the "hot spot" is caused by something that is a positive feedback, but it itself causes a negative feedback. Hope that wasn't muddled. -
carrot eater at 02:00 AM on 28 June 2010What causes the tropospheric hot spot?
Thank you, for this is much, much improved on the previous post. I'll note that while it's difficult to nail down this long-term trend in the observations, the short term behavior is possibly consistent with theory. After all, the satellite records show amplified variability in the troposphere with El Ninos and La Ninas. I think this observation may be related to the same mechanism, just over the short term. -
CBW at 01:58 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
Neven #25, those are pretty pictures of the pole. (Neven has links on his site to the two cameras. Check them a couple of times a day to see the changing skies (and melting ice.)) Does anyone know if this is a common occurrence at the pole, and does it usually happen this early in the summer? Are those yellow things buoys? -
CBW at 01:41 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
gallopingcamel, #63, why would anyone be "panic stricken" about the eventual melting of arctic sea ice when it is simply another consequence of a process we've been witnessing for twenty years or more? And why does it "impress" you that we're not panic stricken? You appear to be insulting us with a backhanded compliment embedded in an "apology." And, for the record, the north pole doesn't have an "ice sheet." An ice sheet exists on land. The north pole has sea ice. -
Peter Hogarth at 01:32 AM on 28 June 2010Sea level rise is exaggerated
neilperth at 14:02 PM on 7 October, 2009 Forgive the late entry here, not wishing to push my own efforts, but many of the sea level rise issues were also discussed here recently. I suggest you read the up to date references and review articles as I took some time assembling them (and have gained few more since). A lot has happened in the past ten years, for example routine precision vertical reference station values from GPS and greatly improved estimates of isostatic rebound and crustal movements, as well as better and more satellite data from several satellites. With reference to your comments about the IPCC, to see what the sea level measuring community is currently saying look at the GLOSS documents and please, read the references. daniel at 22:03 PM on 26 June, 2010 References to the any recent "downturn" in sea level rise are already out of date. The charts above have been updated with latest satellite data including JASON2 and Envisat, see link above. -
Doug Bostrom at 00:46 AM on 28 June 2010Sea level rise is exaggerated
"Look in the mirror?" Calm down, Daniel, remember I'm neither the author of the paper nor the person doing a casual critique of methods without resort to quantitative treatment such as that done by the authors being critiqued. Do the work in detail necessary to show the paper's statistical treatment is undependable and don't imagine that sarcastic remarks are a useful substitute. -
Paul D at 00:46 AM on 28 June 2010What causes the tropospheric hot spot?
In a previous post I suggested a categorisation of signatures and fingerprints. This one appears to fall into the same category as the C13/C12 ratio. A secondary signature. Your first line of proof/defence should be robust primary signatures, backed up by supporting secondary signatures? -
daniel at 00:31 AM on 28 June 2010Sea level rise is exaggerated
Doug, it's simple, look at the graph. A claim of a linear trend is made with 10 data points of clearly very high uncertainties. The recent trend which is of much shorter length in time but of higher resolution and certainty is then tacked on the end and the claim is made that a recent rapid rise in sea level is observed. Any bachelor degree graduate can see that it is not a valid conclusion from the data. The error estimates give us the level of uncertainty, the boundaries within which the true paleo-sea level may reside at a given level of statistical confidence. Do you belive it is valid to say that the sea level did not deviate significantly from the proposed linear trend during this period? It's not my credibility that's at stake here doug, look in the mirror. -
RickG at 00:12 AM on 28 June 2010Astronomical cycles
Looking back at the 100% AGW 1970-2000 IPCC claim, I noticed a discrepancy. On page 1 he states "practically" 100%, but on pages 9 & 13 he leaves the word "practically" out. Isn't that something the reviewers should catch? -
Peter Hogarth at 00:05 AM on 28 June 2010What causes the tropospheric hot spot?
To add further information to Johns explanation, there is also another paper on this topic by Santer 2008, and a highly accessible fact sheet that goes with it. Santer also covers some aspects of this debate (and others) in his May 2010 Testimony for House Select Committee on Energy Independence and Global Warming. He concludes that the discrepancy between modeling and observations has largely been resolved. The expanding nature of our knowledge of both natural climate change processes in the tropics and of the complexity of effects of anthropogenic forcing and warming on these processes is further illustrated in Sherwood 2010 on the effects of tropospheric humidity changes and polewards shifts of atmospheric zones; Seidel 2007 on observed and modeled widening of the tropical belt, and in Chou 2010 on observed and modeled weakening of the tropical atmospheric circulation. All of these and many more strands of emerging evidence add to the robust global climate trends which are already generally accepted and appear consistent with global warming associated with a major CO2 forcing component.
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