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Snorbert Zangox at 22:23 PM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Kevin C and scaddenp It is early morning on Thanksgiving Day here in the US of A, so I have little time to pursue this in detail, but shall do that over the next few days. Kevin C wrote one can estimate fine particle emissions from fuel use data with sensitivity to geographical variations. (-snip-) (-snip-).Moderator Response:[DB] Off-topic snipped.
[KC] Model discussion belongs on this thread where I have addressed your question.
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ranyl at 20:04 PM on 21 November 2012Newsflash: A 4°C warmer world can, and must be, avoided - World Bank
"Thus, given that uncertainty remains about the full nature and scale of impacts, there is also no certainty that adaptation to a 4°C world is possible. A 4°C world is likely to be one in which communities, cities and countries would experience severe disruptions, damage, and dislocation, with many of these risks spread unequally. It is likely that the poor will suffer most and the global community could become more fractured, and unequal than today. The projected 4°C warming simply must not be allowed to occur—the heat must be turned down. Only early, cooperative, international actions can make that happen." From report, I would put that 2C considering it is all model based and the models so far have underpredicted well almost everything. Also doesn't include the permafrost feedbacks recently reproted, nor the facts that it uses a Climate sensitivity of 3C when appears that CS is higher as reproted by Trenbeth and from Pliocene extrapolations. New York already needs to have a planned relocation. Also uses models with far to optimistic carbon sinks, when the sinks are declining and going to keep doing so and the models in the report don't seem to have the loss sulphates effect (warming) or a full realisation of the lagged warming in the ocean (which I suspect is about to return to the surface through the AMOC circulation dynamics). So an optimistic report overall considering the new papers out since September. Then considering the shifts in mean already being seen to say the Russian heat will become a yearly event at 4C is missing the mean shift reality as it will be an 1:5 year occurance at 2C as the mean will have shifted well to the right by then. Then add in the faster tropical expansion, faster dessertification, more rain and geater extremes being seen than in these models and this wake up report is still painting an optimistic future. And as said above Dr. Anderson clearly says 2C is inevitable and 4C hardto avoid, to stay below 2C we need at most a peak 400ppm and 350ppm by 2100 and even that is only a 1:3 chance ish of being below 2C if the Pliocene data is right, 350ppm, 3-5C hotter! Paradigm shift anyone? Who has considered making room available in their homes for climate migrants yet? Stop flying, leave the car in garage whenever possible, turn the thermastat down and wear longjohns, give up on the modile phone, make gifts for christmas rather than consume more, use less energy willingly? Or is it going to be same old same old, replace what we have with "green bling" (PV panels have a very large environmental impact look up tri-nitrofloride and exactly how they made),when at peak 400ppm needed there isn't any carbon to be spending on such things anyway in an objective assessment. But if this is all doom and gloom, then get over your self, it just means living creatively and with ~90% less power, sharing, creating new employments, a new economic paradigm, a truly fair political system that cares for the masses not exploits them (the disparity between the poor and rich is rhe highest it is has ever been), and so on. This requires a gentle transformation with no enemies at all, to create a truly sustainable, vibrant and equitable world. Energetic engagement is a good cure for depression I find, and I find my depression only stems from thinking that no else will do it, but this situation cuts through all known previous possibilities and the choice is everyone together or no one at all, so fighting is futile and thus all that is left is coming together with purpose. And if you now feel that the time of change is now then change for then those around you will be more likely to change in greater and greater numbers as the reality crystalises in the collective consciousness of the world that global warming is the most serious threatening event to human civilization we have faced and at a time when life on earth is amidst a mass extinction event also caused by us (what does happen to the toxins produced by making PV panels????) We also plough billions into the wars for resources yet shouldn't we putting all our resources (everyone included) into the real war, the war to keep global warming within our adaptative capabilities, and not the wars to secure oil and inequitable wealth? Shoudln't we be planning for mass migrations, New York needs relocating as does, Tokyo, Lagos etc....?? Can't we make a problem into solution, with natural building materials and salvage, New York could be re-built elsewhere (albeit without highrises), and create a productive carbon sequestering prodcutive eco-system within its boundaries and lock tonnes of carbon into the walls of its buildings and how much active employment is that? Can't we all to come together, forget judgemental predjudices (Muslims, Christians, racial groups etc), willingly stop excessive consumption, care that we are all humans, and share any excesses willingly? And if all that seems like impossible rhetoric then maybe but the choice here is at last try or global warming will definately be unpleasant and all inclusive, and how foolish would we feel then, knowing we were pre-warned and did nothing or the wrong thing trying to maintain the power addiction we have? -
Cornelius Breadbasket at 19:29 PM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
What I mean is "very likely" is scientific jargon, and misleading in the wrong hands. -
Cornelius Breadbasket at 19:27 PM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
dana1981 @ 7. There is a difference between intelligent and educated ;) -
Kevin C at 19:20 PM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
And here's another one: link. I've plugged this at Real Climate, but it has received no attention, probably because it's by econometricians and published in a stats journal. But it is a completely empirical approach. -
Doug Hutcheson at 18:52 PM on 21 November 2012Newsflash: A 4°C warmer world can, and must be, avoided - World Bank
jimb @ 1, That talk is a "must listen". I have just sat through all 59 minutes of it and can confirm it has cleared the fog from my understanding of where we are and where we are likely to be by 2050. It is a real wake-up call to those of us who already see AGW as a threat to our future. Although Dr. Anderson finishes on an optimistic note, I was not comforted. If all countries achieve the CO2 targets they are aiming at, we are headed for the diabolical future of at least 4oC warmer world, at which level it looks bad for organised human society. (Sorry about the layout - it looks as though sub /sub and sup /sup tags are not working ...) Good thing I am already on anti-depressants ... -
Doug Hutcheson at 17:33 PM on 21 November 2012Climate's changed before
JasonB @ 330, I have followed both your links with great interest. I am not a scientist, but my reading comprehension may be just about up to the task of understanding the pdf, if I filter it through enough red wine. The subd_zone.htm page is fascinating and, boy, has it expanded my vocabulary! Ultramafic, diapirs, amphiboles: I'm just dying to casually drop a few of those into a conversation some time. "8-) -
Doug Hutcheson at 17:00 PM on 21 November 2012Newsflash: A 4°C warmer world can, and must be, avoided - World Bank
Will Mankind wake up before it is too late?
From polls recently, it seems about half of us are awake and the other half have hit the snooze button on their alarms. That half are being wooed back to sleep by voices soothingly whispering "Don't worry - there is plenty of time, and anyway the alarm is a hoax." Will enough people wake up to tip the balance in favour of effective action, before it is too late? Just because we did it with CFCs and DDT does not mean much, because the cause and effect in each case was close enough in time for the problem to be visible to even the sleepiest. Not enough people live near the Arctic to see what is happening here and now and the voices of those that do see it are being drowned by the sound of snoring. AGW cause and effect are so far apart in time that the sleepyheads cannot see the problem. We continue to advocate change to avoid a future hazard, not one that is clear to the misinformed. Will mankind wake up? Yes. Before it is too late? I doubt it. Our species will get the future it deserves, one way or the other. -
JasonB at 16:59 PM on 21 November 2012Climate's changed before
Doug H, Completely off-topic for this post, but related to the subject of Richard Alley's video: I recently came across research that showed that some subducting plates may make it all the way down to the bottom of the mantle, literally scraping along and piling up on the core, thousands of km down, because rock is such a poor conductor of heat that they take a really long time to melt. I found this image of plates plunging deep within the earth to be quite fascinating, although I can't remember where I read it now. I just did a quick search and turned up this paper: http://www.es.ucsc.edu/~ahutko/Publications/HLGR_Nature_2006.pdf Look at figure 4 in particular. As Richard Alley's song indicates, and this page confirms, the volcanoes above subduction zones are not actually emitting the melted plate (as I had assumed) but rather magma that has melted due to the water being carried down by the melting plate. -
Doug Bostrom at 15:28 PM on 21 November 2012Climate's changed before
JasonB:Three other witnesses aren't sure what they saw and even disagree with each other on what happened, but all agree it couldn't have been murder because that would require the state to raise taxes to employ a police force and one objects strenuously to the 97 others being so certain of what they witnessed.
Touché. -
jimb at 14:38 PM on 21 November 2012Newsflash: A 4°C warmer world can, and must be, avoided - World Bank
I listened to Dr. Kevin Anderson's talk, "Real Clothes for the Emperor" and he seemed quite convinced that restricting the temperature rise to 2 degrees C was pretty well impossible. He seemed to make some good points. His presentation is available in many places, including here; http://climatesoscanada.org/blog/2012/11/19/watch-kevin-anderson-real-clothes-for-the-emperor-nov-6-2012-lecture-at-bristol-university/ My appologies for the clumsy link. -
Doug Hutcheson at 13:20 PM on 21 November 2012Climate's changed before
JasonB @ 327, That is an extraordinary piece of teaching. A 3 minute video I will remember for a long time. I've even emailed the link to my family, so they can all enjoy it. If only science had been this much fun at school, my career path would have been very different. Thanks for posting it. -
JasonB at 12:51 PM on 21 November 2012Climate's changed before
Composer99: You are right, initially I took the large gap before the last two paragraphs as a "quote delimiter" but afterwards it occurred to me that it might still be part of the quote and checking the page at the URL given confirms this. Sorry Bill. Looking at what was written on that page, someone has clearly gone to a lot of effort to put together an argument that a little more effort on research would have told them was attacking a strawman. Even a cursory examination of the IPCC reports shows that mainstream science is well aware that "other factors besides atmospheric carbon influence earth temperatures and global warming" because it even quantifies those other factors in the attribution analysis! That mistake then leads to the erroneous conclusion that all that's required to disprove AGW is to show that other factors must have also influenced climate in the past. The underlying logic is the same as "Lightning has caused fires long before man came along, therefore arson doesn't exist". Or, "murder doesn't exist because people have died of natural causes in the past", used by the defence in a murder trial where the accused was seen by 97 witnesses standing over the body of the victim with a bloody knife in his hand shouting "I'm glad I killed the bastard!". (Apologies to BlackAdder...) (Three other witnesses aren't sure what they saw and even disagree with each other on what happened, but all agree it couldn't have been murder because that would require the state to raise taxes to employ a police force and one objects strenuously to the 97 others being so certain of what they witnessed.) Doug H: If you liked the talk, be sure to check out Ring of Fire. :-) It's hard to reconcile the reality of a funny, geeky climate scientist with the portrayal of them by commentors on sites like WUWT and Climate, Etc. -
Doug Hutcheson at 12:01 PM on 21 November 2012Climate's changed before
JasonB @ 324, Thanks for the link to Richard Alley's talk. He has a great way of making a 45 minute lecture seem to short. What a great teacher. -
Flakmeister at 11:37 AM on 21 November 20122012 SkS Bi-Weekly News Roundup #1
Re: Vroomie Much appreciated, I just celebrated my 6th anniversary at the Drum. Any serious student of Peak Oil has passed through the site. The commentators were guilty of predicting a "fast crash" and that is not being bourne out. They underestimated "The Last Magician of Modern Monetary Theory", i.e. printing a few trillion dollars to throw into a deflationary death spiral can buy time. Personally, I think that we are are on the wrong side of the Event Horizon, in a large part because of Peak Oil... As for AGW, I was never a real skeptic, I just never appreciated how fine the line was upon which our dear species traipses through our existence... I also think that the solution to Fermi's Paradox is now evident; can a technological society overcome the fossil fuel transition and their variation of climate change? Every star warms as it ages, therefore a GHG richer environment is necessary for a liquid water planetary biosphere earlier on. It seems like it is therefore guarenteed for a planet to have more fossil fuels than which it can safely burn... -
Composer99 at 11:37 AM on 21 November 2012Climate's changed before
JasonB: An excellent explanation. That said, I would be careful in attributing too much of Kiwi Bill's comment as his own. As he notes, he is extracting a commentary from a site (in this case, geocraft) and unless I am mistaken, everything after the line "From: (website link)" is from geocraft. (Correct me if I am wrong, Kiwi Bill.) -
JasonB at 10:47 AM on 21 November 2012Climate's changed before
Kiwi Bill, You need to be very careful comparing much earlier times to today because physics tells us that solar output was much less. In fact, the prediction by physics that the sun was much cooler before yet the geologic evidence showed liquid water on Earth was known as the "Faint Young Sun Paradox" which is resolved precisely by noting that CO2 levels were higher then. In other words, the Earth's temperature is a consequence of all forcings acting on it, and if the solar irradiance is less then higher levels of CO2 are required to maintain temperatures similar to today. The next question is what happy coincidence was it that caused the Earth to always seem to gravitate towards a certain range of temperatures, rather than e.g. stay stuck in a snowball Earth forever or boil away the oceans? Why were CO2 levels just the right amount higher then to maintain liquid water on Earth? The explanation is absolutely fascinating to me, and explained exceptionally well by Richard Alley in this thoroughly entertaining talk. Essentially, CO2 acts like a thermostat, automatically adjusting its levels to maintain "nice" conditions on Earth over geologic timescales. When temperatures are too low, ice sheets form, covering the rock -- the same rock that normally CO2 would react with to form carbonates. Since the rock is covered by ice, and CO2 is emitted by volcanos, CO2 levels rise until the greenhouse effect is strong enough to melt the ice, expose the rock, and start reacting with the rock like crazy, bringing CO2 levels down again. Conversely, if CO2 levels are too high, the rate of rock weathering increases because it is a temperature-dependent reaction. Since the injection of CO2 by volcanos is roughly constant over long periods of time but the removal of CO2 by rock weathering increases with temperature, this acts to bring CO2 levels down and therefore lowers the temperature. This means that our current massive increase in CO2 will ultimately be corrected by the system but unfortunately it operates on long timescales (compared to what's important for humans) so it doesn't help us with our current problem. Anyway, watch the video because Richard Alley explains it in much more detail and more entertainingly than I could!Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming.
Of course, climate science has always said that, which means your comment "According to greenhouse theory, Earth should have been exceedingly hot" is not correct because "greenhouse theory" is precisely what explains why the temperatures were what they were then despite the fainter sun. The reason for the focus on CO2 today (and to a lesser extent, other greenhouse gasses) is because they are the main factor influencing the change in Earth temperatures in the recent past. If you look at the official explanation for the early 20th century warming you'll see that much of that is put down to an increase in solar irradiance at that time. If there had been a further increase in solar irradiance in the last 50 years then the temperatures would be even higher and the IPCC reports would have apportioned a greater share of the recent temperature rise to that increase. The fact is, however, that over the last 50 years or so it just happens to have been CO2 that is responsible and, luckily, this is one forcing that we can do something about because it was us that lead to that increase in forcing -- without our CO2 emissions the temperature would have cooled slightly over the last 50 years. -
Kiwi Bill at 09:53 AM on 21 November 2012Climate's changed before
As a scientifically ignorant person, and too old to be trained, could I ask if some of you clever chaps could tell me what is wrong with the picture contained on the following site. It purports to show that despite CO2 levels which were often very much higher than at present, temperatures on the planet stabilised around 22C for most of the planet's geological history, with only three 'relatively' short periods, including the present, when temperatures dropped to current levels. The table included on this site is entitled: "Global Temperature and Atmospheric CO2 over Geologic Time". It has a note following saying: "Late Carboniferous to Early Permian time (315 mya -- 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period )". The table is allegedly sourced as follows: " Temperature after C.R. Scotese http://www.scotese.com/climate.htm CO2 after R.A. Berner, 2001 (GEOCARB III) " Please don't ask me to study every thread on every page to find out for myself. That would be a bit like saying no-one should make even an implied comment on a subject unless they know every little detail. From: http://www.geocraft.com/WVFossils/Carboniferous_climate.html ------------------------------------------------------- Similarities with our Present World ------------------------------------------------------- Average global temperatures in the Early Carboniferous Period were hot- approximately 20° C (68° F). However, cooling during the Middle Carboniferous reduced average global temperatures to about 12° C (54° F). As shown on the chart below, this is comparable to the average global temperature on Earth today! Similarly, atmospheric concentrations of carbon dioxide (CO2) in the Early Carboniferous Period were approximately 1500 ppm (parts per million), but by the Middle Carboniferous had declined to about 350 ppm -- comparable to average CO2 concentrations today! Earth's atmosphere today contains about 380 ppm CO2 (0.038%). Compared to former geologic times, our present atmosphere, like the Late Carboniferous atmosphere, is CO2- impoverished! In the last 600 million years of Earth's history only the Carboniferous Period and our present age, the Quaternary Period, have witnessed CO2 levels less than 400 ppm. Global Temperature and Atmospheric CO2 over Geologic Time Late Carboniferous to Early Permian time (315 mya -- 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ). Temperature after C.R. Scotese http://www.scotese.com/climate.htm CO2 after R.A. Berner, 2001 (GEOCARB III) Compare Oxygen (O2) concentrations. See an estimate of CO2 concentrations over the past 15,000 years, based on plant stomata. There has historically been much more CO2 in our atmosphere than exists today. For example, during the Jurassic Period (200 mya), average CO2 concentrations were about 1800 ppm or about 4.7 times higher than today. The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Cambrian Period, nearly 7000 ppm -- about 18 times higher than today. The Carboniferous Period and the Ordovician Period were the only geological periods during the Paleozoic Era when global temperatures were as low as they are today. To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today-- 4400 ppm. According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming. -
scaddenp at 09:23 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
So things you can estimate reasonably well is FF consumption, BC signatures etc in pre-satellite era. Have to derive aerosol from this. see for example this one but following citations etc, you will find a rich literature. For what the forcing used by the GISS group are derived from then, follow the literature trail from Hansen et al 2007, "Climate simulations for 1880-2003 with GISS modelE." You might also be interested in a completely alternative approach (straight curve-fitting of forcings) in Benestad and Schmidt 2009 for the 45-75 dip. I dont see how you leap to "they affect the accuracy of the model predictions. " from the paper. You have a good predictive climate model, so you play with different forcings to compare their efficiecy on climate change. This allows predictions about the importance of specific forcing - in particular the paper was interested in BC and mathane. I suggest you read the whole paper. It is not about model validation. -
Kevin C at 08:57 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Snorbert: It's a good question, and by coincidence I've been digging on this one today, although I certainly don't have a full answer. Gavin at Real Climate would be a better person to ask, but we might be able to get somewhere together. The Skeie et al 2011 papers are probably a good place to start, the first is here and the second is here. The Skeie forcings look as though they contain a rather more pronounced mid-century drop than the Hansen or CMIP5 sets. My current impression is that atmospheric chemistry models of aerosols are developed by chemists (these have nothing to do with climate models) and validated against modern measurements (both satellite and ground based, using microwaves, IR, visual and radar). Given that the aerosol effect show considerable geographical variation, this information can be used in addition to time dependence as a validation criteria. That gives you a lot of validation power. The results are then correlated against known fuel use figures. Fuel use figures from earlier dates (e.g. Bond 2007) are then used to reconstruct aerosol emissions from before the direct observations were available. I've only looked at Skeie, I don't know if other studies have taken different approaches. -
Wigley and Santer Find the IPCC is too Conservative on AGW
Snorbert Zangox - Stratospheric forcings estimated from ejecta mass, from regional optical extinction, and then satellite measures (depending on time period), calibrated against the later and better measured values for all of these, is the best data available. Hence it's the best starting place for investigation. Likewise the tropospheric forcings are estimated from sources on how much fossil fuel was burnt, and where (quite good records there) and model estimates of how that got distributed and it's effects (again, based on modern day dispersal patterns). Again, these are the best estimates available to the modelers. There are uncertainties, and there will always be uncertainties, particularly in historic data. But if you want the best model possible from the data, you start from the best estimates of that data you can obtain. I would suggest further discussion of model development take place on a more appropriate thread, such as here. -
Snorbert Zangox at 08:27 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
I looked at some of the references in the sources that you provided and found two types of information. One was for example estimates of particle concentrations based on estimates of particle loads from volcanic eruptions (based, I suppose on contemporaneous literature descriptions of the events). I find this somewhat troubling as a source for input data to climate, or any other models. The other appears to be use of the climate models to predict past values for forcing agents. For example I found the following text in Hansen et al. Geophys. Res., 110, D18104, doi:10.1029/2005JD005776. "We use a global climate model to compare the effectiveness of many climate forcing agents for producing climate change. We find a substantial range in the "efficacy" of different forcings . . ." This one I find especially troubling in that it sounds like using the models to estimate the effectiveness of albedo changers based on how they affect the accuracy of the model predictions. Is anyone familiar enough with these estimates to describe how they actually work? -
Daniel Bailey at 07:39 AM on 21 November 2012It's El Niño
It is said that it is only in the act of teaching that an educator can truly become the master of what he teaches. Mastery awaits Mr. Tisdale... -
Wigley and Santer Find the IPCC is too Conservative on AGW
Snorbert Zangox - See, for example, the GISS model forcings. These include the references and data for tropospheric and stratospheric aerosols as used in their model. I suggest looking at those references for an overview. Other models and scenarios will have similar sources, although the details will of course vary. -
It's El Niño
As an addendum, Tisdale should also look at John Nielsen-Gammon's analysis, which clearly shows grouped El Nino, La Nina, and ENSO-neutral years all trending upwards in temperatures over the last 50 years. This can hardly be the result of (as Tisdale claims) one or two decades of El Nino heavy ENSO activity.
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Snorbert Zangox at 07:26 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Tom Dayton and Composer99. I understand, in general terms, how the models work; qualitatively they work the same way that the parameterized models commonly used in calculation of flow in pipes work. That is construct a model that contains the appropriate factors, then conduct measurements to define values for the various parameters included with the term for each important factor. My question is how did the modelers find values for the concentrations and particle size distributions of the particles in the air between 1945 and 1975? These parameters, among others, are critical as Composer99 noted, if one is to calculate the albedo change attributable to particle concentrations. -
DSL at 07:09 AM on 21 November 2012It's El Niño
What an excellent chance for Bob Tisdale to argue a specific point and potentially advance the science. Come on, Bob. I'd like to hear your ENSO argument without the heavy sauce of rhetoric. Surely there are at least a few people here who can understand the dynamics as well as you. Surely you're capable of explaining it to the less gifted of us, no? You can preach to the choir all day long at WUWT, and all you'll get is blank-eyed head nodding. Here you have the chance to convince the unconvinced, to put your argument to the test of fire, and to engage in the perfectly healthy behavior of getting feedback from the community. Surely SkS can set up a forum for extended dialogue on a specific issue or two (say ENSO and SST in general or OHC?). I really respect Pielke Sr. more now for wading into the thornbush and having his say. It's refreshing when the discussion isn't rhetorical cruise missiles lobbed from thousands of km away but is instead look-me-in-the-eye-and-tell-me-I'm-not-human dialogue, and I think SkS is the best place for a rhetorically toned-down discussion of the issue: wide reach (continually referenced across the mainstream news network) and a relatively effective comments policy. -
Composer99 at 06:52 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Further to Tom's point, since models are physics-based, they should be (and indeed, to my knowledge, are) able to account for cooling periods with known factors (in the 1945-1975 case, the dramatic increase in the aerosol load in the atmosphere) without any "correction factor" whatsoever. While our knowledge of the pertinent physics is currently very good, and improving continuously, it is still not 100% so I would not expect any model to 100% accurately hindcast past temperatures. -
Tom Dayton at 05:55 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Snorkert Zangox, first we need to make clear that the models are not simply "corrected" until their temperature outputs match observations. Instead, the modelers notice mismatches between hindcasts/forecasts and observations, then use those as clues to guessing which aspects of the physical models are responsible for those particular mismatches. Then the modelers use independent physical evidence to improve those aspects of the physical models. Finally they run the models again to see if the mismatches have been reduced. Sometimes that helps, sometimes it doesn't and it can even make the mismatch worse. (If a now-improved aspect's error previously was compensating for some other aspect's error in the opposite direction.) -
Snorbert Zangox at 05:42 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Will someone please describe to me how the modelers devised the correction factors to their models that accommodate the cooling that we saw between ca 1945 and 1975? Thanks. -
Bob Lacatena at 05:21 AM on 21 November 2012It's El Niño
I'm still waiting for someone to cogently present Tisdale's case (without charging for it). -
vrooomie at 04:56 AM on 21 November 20122012 SkS Bi-Weekly News Roundup #1
Flakmeister@6: As a geologist, who's fairly familiar with the peak oil rationale, your thoughts are quite illuminating, and WAY shorter and to the point than almost any I've seen, even on The Oil Drum. Though I am almost always about being as positive as possible, let me add this much to your last sentence, and this is a position I've held since the early days of using 'corn squeezin's' to augment liquid vehicle fuels: Food-as-fuel is an utterly and totally irrational, immoral, and *stupid* use of inputs as ever there was. It *only* exists because of the monied interested (read: large agribidness welfare, aided and abetted by stupid gummint policies), the evidence of which I see, quite literally, on a daily basis as I live surrounded--to the tune of 30K+ acres--by the stuff. In a world where food shaortages exist, it ought to be outlawed. Bottom line is, the peak oil hypothesis hasn't gone "up in flames:" it has simply been shown to be a hypothesis that has added data, and therefore, becomes a newer, better-supported hypothesis. We *will*, one day, run out of petroleum: I'm not sure we'll survive that long, if current studies are anywhere clsoe to correct, vis-a-vis global temperature rise. Now, Dikran Marsupial will likely moderate me because, as he has stated on a prior occassion, of me "holding back." >;-) -
dana1981 at 04:53 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
On a related note, in a new blog post today, Judith Curry criticizes UCAR's Michael Morgan for agreeing with the IPCC's global warming attribution statement, apparently because she believes the too-conservative statement is too confident (shades of the Uncertainty Ewok). In the same post she also reveals that she thinks we can improve climate model projections by improving weather predictions, among other face-palm comments. -
Composer99 at 02:43 AM on 21 November 2012It's El Niño
KR: I believe there is only one appropriate response to Tisdale's claim with respect to Skeptical Science & its contributors' ability to "fathom the subject matter" regarding his confusion surrounding ENSO and climate forcings. -
dana1981 at 02:19 AM on 21 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Cornelius - it seems to me like the IPCC was assuming its audience is intelligent by assuming they could equate "very likely" with "greater than 90% probability" without having to spell it out. Though they probably would have saved themselves some headaches by just spelling it out each time. -
It's El Niño
Tisdale has now stated that "No one from SkS will never be able to find any flaws, because they very obviously can’t fathom the subject matter." Hmmm - claims that nobody can fathom your understated brilliance? Regarding a blog theory contradicted by historic observations (long term neutral average of ENSO), current observations (TOA spectral changes in GHG absorption that demonstrate GHG causation, not ENSO), and basic thermodynamics (claiming atmospheric warming comes from recent excess of El Nino's over La Nina's, yet the oceans are warming too - where does all that energy come from)? All of which has never been discussed or examined in the peer-reviewed literature, by those who study this data? Let alone the issues with his "evidence" lacking any connection to statistical significance... I was actually rather surprised to find that claims of "nobody can fathom my subject matter" isn't part of the Crackpot Index; it really belongs there. Ad hominem fallacies aside - if you cannot explain your theories well enough to be understood, you probably don't understand them yourself. --- Kayell / Kristian - In answer to your original question, 'theories' such as Tisdale's have no place in a scientific discussion - beyond noting that they don't hold up to examination. -
Cornelius Breadbasket at 22:10 PM on 20 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
perseus @ 6. I rely on the scientists on this site to do the data collection and number crunching but I do know about communication. The IPCC missed a trick by using the phrase "very likely". If they had used the phrase "greater than 90% probability" they would have been far clearer, more accurate and less condescending. In my experience is is essential to understand that your intended audience is intelligent, something that this site does brilliantly. -
ranyl at 20:51 PM on 20 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
It is interesting that the natural forcing plus all human forcings underpredicts warming 69.1% of the time, figure 7b, yet just human forcings alone underpredict only 60.9% of the time, yet in graph 6 it seems the dashed only human forcing line is nearly always greater than observations; presume it must have a wider variance to account for this 60% underestimation. Wonder what CS resulted in the most accurate models over the range of aerosol uncertainities with natural variation incorporated, as if ~70% models underpredict warming to 2005, then that is suggestive of a missed warming influence or a higher CS is needed which might be in keeping with other recent CS results. Seems that CS is more and more likely to be higher especially as SO2 emissions have increased since China and India industrial revolutions and brown clouds have been shading the surface as well (despite increasing overall atmospheric energy at altitude), meaning the surface temperature records over Asis will have been reduced considerably in the last 20 years or so. It is also sobering that if humnan aersols are lost from the atmosphere, that adds most likely another 1.1W to the warming influence, add in the self expanding albedo effect forcing now kicking in, and the lagged warming due oceanic mixing, then a doubling of the current warming force seems possible within 5-10years if fossil fuels are not used anymore. And the current forcing is driving a climatic warmign at a rate ~3x greater than found in the geological time record. So if stopped all emissions today, that would mean from 2020 to 2050 (as GHG in the atmosphere woudl not drop at all, due to permafrost melt and very slow drawdown) there should be a rate of warming of ~0.3C or more. Add in that natural variation in terms of sun and El Nino have tended to cooling in the last 10 years, thne is highly likely that the earth shoudl also experience some natural warming as well. That leaves us with ~1.8C above pre-industrial by 2050 by stopping all emissions now. As GHG after that are likely to increase due to eco-system distress and further permafrost releases and the need for a massive carbon sequestration becomes urgent. Adaptating to 1.8C alone considering the changes already being seen is going to take a mass effort by everyone in the same direction. Leaves a carbon budget of zero, therefore every ounce of carbon from now on is another ounce that needs to be removed from the atmosphere by 2050-2100, in-order not to slip beyond the limits of the adaptative capacity of our current civilization. How much carbon are you prepared to gamble? 400ppm? Immediate goal 350ppm 2100? Long term target. And as climate change becomes the most likely threat to the whole civilization we still fight over oil and aren't prepared to even give up the mobile phone. The scale of transformation needed is such that in this effort to prevent irrational amounts of global warming occuring whilst creating a sustainable future needs everyone to come together rather than waging war or hoping for divine intervention as we are now. -
Kevin C at 20:06 PM on 20 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
One of the key results the paper reinforces (although it has been stated often enough before, e.g. Hansen & Sato 2011), is the 20th century climate creates a strong dependence between the possible values of aerosol forcing and transient climate response. I'm currently playing with a two box model, and using Hansen's (unadjusted) aerosol forcing to fit 20thC climate, I get a TCR of about 1.65C. If I set the aerosol forcing to zero, the TCR drops right down to 0.6C. If you know the aerosol forcing, 20thC climate gives you TCR. If you know TCR, 20thC climate gives you aerosol forcing. As JCH has commented at Tamino's and Curry's, if the climate skeptics were joining the dots they would "sell natural variation; buy aerosols". -
perseus at 18:36 PM on 20 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
"Some of these criticisms stem from a failure to understand that the term "very likely" has a specific numerical definition, meaning greater than 90% probability." Let's hope the IPCC accept this evidence to upgrade their level of confidence. Uncertainty fuels the Denier community, confuses the public, and provides the excuse for inaction. -
Doug Hutcheson at 17:34 PM on 20 November 20122012 SkS Bi-Weekly News Roundup #1
Flakmeister, that's precisely our problem. The world we live in is dominated by the MROMI equation, where M = Money. Money knows no ethics; profit knows no social justice. Unless we can legislate in ways that make the Fossil Fuel MROMI equation unattractive, we will be condemned to sit on the sidelines of history, wringing our hands and saying "Told you so!", while watching our planet go to hell in a handbasket. Corn-to-ethanol is a perfect example of blinkered vision. -
dana1981 at 15:00 PM on 20 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
Thanks adelady - 7 papers actually! If you click the link in the final paragraph, it goes to my discussion of the other 6. -
adelady at 14:51 PM on 20 November 2012Wigley and Santer Find the IPCC is too Conservative on AGW
This is worth saving for reference. I know I've often had the 'feeling' that I've seen evidence that the ghg contribution was >100% of temperature change, but I've never been able to remember why or who said what or how it works. Having a single paper focused on precisely that issue is what I didn't know I was waiting for. Nicely done, dana, btw. -
Ken in Oz at 08:09 AM on 20 November 2012New research from last week 46/2012
Curious about the Global Energy Balance paper. It appears to be a 'snapshot' that isn't about following trends. Is it likely to be a fixed point for future reference? Whilst the way energy moves around within atmosphere and ocean have lots of room for uncertainties, the actual in and out of energy at Top of Atmosphere seems to me to be the defining measure of GHG contributions to warming. CERES and SORCE satellite data for Top of Atmosphere - any pointers to discussion of their limitations and their results, like graphs that show the energy out compared to energy in ie mapping and quantifying the actual observed changes to energy balance at TOA? -
Bernard J. at 07:24 AM on 20 November 2012It's El Niño
As other have noted above it's been directly pointed out to Tisdale by many people (including me) that his argument breaks the first law of thermodynamics. He always blathers around the point but never addresses it properly. Although most would dismiss his pseudoscience as preposterous, at some point it may actually be worth a coda to formalise rebuttal of his nonsense. It's a sad state of affairs though that it might have to go to that extent... but then, that describes just about all denialism. -
Tristan at 03:32 AM on 20 November 2012It's El Niño
I find it strange behaviour to insist anything that has no established science behind it. The thing I took from his video was merely how certain of his conclusion he was. -
Flakmeister at 02:44 AM on 20 November 20122012 SkS Bi-Weekly News Roundup #1
Re: Peak oil Sorry Peak oil is very simple: it is the point where extraction rate of crude oil is maximal. We have been on a plateau for 8 years running. Do not be fooled by claims based on "All Liquids", NGL and "refinery gains" are not oil, bio-fuels with a lousy EROEI are not oil. On a net BTU basis, liquid fuels are basically flat over the past 8 years... The peak is ultimately geologic in nature, that does not mean that economics or political events are not important. The upside of the Hubbert curve was driven by geology, however, the shape of the plateau and downside will be driven by economics.... New reserves such as tight oil and gas will not result in a significant increase in global production. To put the Bakken into perspective, if one doubled the latest USGS estimate of recoverable oil to ~60 billion barrels, it would change the worlds proven and probable reserves by about 5%.... Also do not become overly enamoured of EROEI arguments, it is a question of profiting from BTU arbitrage. High value liquid fuels produced by utilizing lower cost NG and coal will continue as long as a profit is to be made. Hence, my referring to the US Corn-to-ethanol industry as our very own version of the Easter Island logging industry.... -
Composer99 at 01:23 AM on 20 November 2012New research from last week 46/2012
Bertrand Russell is attributed with the comment "the mark of a civilized man is the ability to read a column of numbers and weep" (although my brief researches did not find a conclusive source of him stating such a thing). The graphic derived from Wild et al (2012) showing the TOA and surface energy budgets is surely worth shedding tears. -
Rob Painting at 00:39 AM on 20 November 2012It's El Niño
Tristan - Tisdale replied basically insisting La Nina is responsible for ocean warming. Colour me unimpressed. La Nina is an interval when the Earth sees a net gain in energy, and El Nino a net loss, but this isn't some novel observation, I've discussed this, for instance, in this SkS post: Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline'. See Figure 3 and the associated heading discussion. More importantly The ENSO-related energy fluxes balance out to zero in the long-term. If they didn't (as Tisdale seems to think) the planet would go on warming indefinitely. It's the same problem those Scafetta climastrology papers have - not only do they have to match recent observations, they also have to match with older observations - and that's where they quickly run aground. Increased levels of greenhouse gases heat the ocean, by lowering the thermal gradient in the thin cool skin layer of the surface. This reduces the amount of heat lost (from sunlight) to the (typically) cooler atmosphere, and the oceans warm as a consequence. That's why there is such a striking correlation between atmospheric carbon dioxide and temperature (aka ocean heat content) in the ice core reconstructions.
Vostok ice core records for carbon dioxide concentration (Petit 2000) and temperature change (Barnola 2003)
However, ocean heat can indeed vary dramatically in the short-term due to changes in aerosols, and especially cloud cover, in the atmosphere (which alters the amount of sunlight heating the surface ocean). So if you just look at the data, without a proper statistical analysis (as Tisdale is prone to), you can convince yourself of anything.
If Tisdale's misunderstandings gain any traction, we'll get around to debunking it, but it's not a priority at the moment.
-
gws at 00:37 AM on 20 November 2012The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
correction the last arctic stratospheric ozone loss episode occurred not 2011/2012 as I said above, but spring 2011 Nature article here
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