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NewYorkJ at 02:53 AM on 30 August 2011Mythic Reasoning about Climate Uncertainty
How can anyone seriously claim conservative IPCC statements lead to overconfidence as claimed in the conclusion? They go out of their way to highlight uncertainty. I haven't seen any attribution study that can assign 50% or more of the warming of the last 50 years to the net of natural causes, yet the IPCC leaves that open to a 10% chance. Then there's the best estimate that natural contribution has been nil or even a little negative. Also take a look at statements from Dr. Andrew Lacis. Lacis at NASA on Role of CO2 in Warming Also see: More Curried Leftovers -
Tom Curtis at 02:33 AM on 30 August 2011Temp record is unreliable
econ101ab @223, it is very late here, and I am very tired, so I will only respond to your second point tonight. Essentially, you are ignoring the fact that the temperature calculations are for temperature anomalies rather than for absolute temperatures. An extrapolation of absolute temperatures would be absurd for exactly the reasons you give. The temperature anomaly, essentially the absolute temperature minus the mean temperature over some period, will not be so affected. Specifically, if it is an unusually warm day at Palm Springs, it will probably be an unusually warm day at Big Bear Lake as well. The difference in their anomalies on any day will be small even though the difference in their absolute temperature on every day is large. This is explained in greater detail in On Averages and Anomalies Part 1. (Link give by KR in 219 above.) -
econ101lab at 02:13 AM on 30 August 2011Temp record is unreliable
Philippe, you question my sources. What do you think I am doing here? Rather than snarky comments about my motives, I appreciate the willingness of KR, Tom, and DB to show me how the site works and give me a start on how to find information. Geez, lighten up.Moderator Response: You'll find less "snarkiness" in responses to you if you refrain from writing so stridently and confidently before you have read up on the rudiments. Folks here have a hair trigger for such behavior because it happens so often. Your failure to understand the really, really fundamental fact that temperature anomalies are used, is exactly such a case. -
John Hartz at 01:30 AM on 30 August 2011Tar Sands Impact on Climate Change
"Einstein said to think and not act is a crime," James Hansen tells SolveClimate News. "If we understand the situation, we must try to make it clear." Source: "NASA's Hansen Explains Decision to Join Keystone Pipeline Protests" by Elizabeth McGowan, SolveClimate News, Aug 29, 2011. To access this informative and timely article, click here. -
econ101lab at 01:15 AM on 30 August 2011Temp record is unreliable
Tom, I will read your recommendation re: Ned's article. I fully accept your observation of the tenuous nature of macro economics as accurate due to the long time spans needed for observation and the virtually infinite and unobservable micro variables which can cumulatively affect the macro picture. This is why I have a tough time getting my arms around the "settled science" position. I'm not trying to be difficult but when two thirds of the planet isn't observed (either water temp or air temp over water) and one of the most significant variables isn't even modeled or clearly understood (clouds and cloud formation), the certainty smacks of intellectual hubris. As a non-climatologist, are there other untracked or unobservable variables of which I am unaware? Again, not trying to be a butt here. While I think Keynes and Galbraith were wrong based on the observable record and Friedman on the money, others dispute that looking at the exact same historical record (of course perhaps taking different micro impacts into account). OK, I've begun doing the reading suggested by KR (thank you again KR). I used the search function, unsuccessfully, to try and find previous posts for a few questions I have. My questions are regarding temperature records and how they're calculated. I ask the questions because I do not understand so please take them in that vein. First, wouldn't the cumulative error in a cell or block that is extrapolated vs observed, quickly make the data from that cell meaningless and affect the long term results more the longer it was used? Particularly if it was in close proximity to the central station and hence had a greater weighting? Second, Mr. Tamblyn does an excellent job laying this out for a non-climatologist. I understand the teleconnection concept and it makes sense as long as the station extrapolations take place from similar altitudes. I can think of numerous locations where I have been personally, where locations 50-60 miles apart might vary 50-60 degrees F. Palm Springs vs Big Bear Lake in California during the winter is an excellent example. I have played golf in the morning in 80 degrees in PS and then gone to the top of the tram where there's snow on the ground and the temp is in the 20's. If Big Bear were to be extrapolated from either LA or Palm Springs (both about 60 miles away) they would have significant weight due to proximity but no relevance. And is his contention that the Andes and coastal Peru have the same weather systems passing over accurate? The Andes are much higher than the San Gabriel Mtn's and the SGM's actually stop weather from the coast from moving inland. Meaning that one location (LA) has totally different weather from one 90 miles away (PS) precisely due to a geographical feature. Western and eastern Colorado create a similar situation. As do the Ngorongoro Crater and the Serengeti (went both places this summer, put it on your bucket list!) I looked at the gridded map and can see numerous places globally where this could logically happen. I see how it can be adjusted for if there are only occasional lapses in observed temp, but how is it adjusted when there is no station? Satellite? Thank you. Back to my homework. -
Joshua at 01:13 AM on 30 August 2011Mythic Reasoning about Climate Uncertainty
"Crisis of confidence, perhaps" I question just who is having this "crisis of confidence." I think that Judith is projecting her own "crisis" onto the larger public without evidence to support her speculation. That projection is fueled by the general vibe among her "denizens," who seem to be similarly affected. When I see what I consider to be overextrapolation, I tend to wonder about the very same sort of "motivated reasoning" that used to concern Judith with respect to the reasoning of "skeptics," predominantly. Now Judith seems predominantly concerned her about the "motivated reasoning" of what she calls the "climate establishment." What motivates that change in the focus of Judith's scrutiny? -
Composer99 at 01:10 AM on 30 August 2011SkS Weekly Digest #13
Grand Poopah is no doubt the title my wife & I will be giving Mini-Composer once he's born. -
Bob Lacatena at 01:02 AM on 30 August 2011Climate Sensitivity: Feedbacks Anyone?
16, Eric the Red,Although the sea ice has been present for 5000 years, it has been anything but constant.
I do not agree with this statement. Do you have any citations to support this assertion? Can you quantify the variability that you conjecture has occurred?Moderator Response:[DB] EtR must be acknowledging the unprecedented loss of Arctic Sea Ice ongoing in today's time (unprecedented over the past 5,000 years)...
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muoncounter at 01:02 AM on 30 August 2011ConCERN Trolling on Cosmic Rays, Clouds, and Climate Change
This bit on Nigel Calder's blog has the 'it's cosmic rays' folks shouting, 'we told you so!' Calder apparently has dramatized the sequence of events in one experimental run to great success. I've interspersed a few questions that seem unanswered in his rendition.In an early-morning experimental run at CERN, starting at 03.45, ultraviolet light began making sulphuric acid molecules in the chamber, while a strong electric field cleansed the air of ions. It also tended to remove molecular clusters made in the neutral environment (n) but some of these accumulated at a low rate.
Q1: That electric field also acts as shielding. Why are any molecular clusters accumulating in a shielded chamber with no particle beam input?
As soon as the electric field was switched off at 04.33, natural cosmic rays (gcr) raining down through the roof of the experimental hall in Geneva helped to build clusters at a higher rate.
Q2: Most cosmic ray workers would interpret 'natural cosmic rays' as the background flux of muons produced by atmospheric interactions with the solar wind (usually referred to as solar cosmic rays). How do they automatically identify this background as GCRs? And what sort of electric field shielded the chamber from muons (negatively charged) with energies on the order of GeVs?
How do we know they were contributing? Because when, at 04.58, CLOUD simulated stronger cosmic rays with a beam of charged pion particles (ch) from the accelerator, the rate of cluster production became faster still.
Q3: 'Stronger' in this context must mean higher energy. The original experimental design called for a pion beam on the order of 600 MeV, no 'stronger' than the background muons. Further, charged pions decay quickly to muons. What does this utterly critical statement mean? Are they actually investigating solar cosmic rays and not GCRs? Are they now saying that solar cosmic ray muons cause cloud nucleation as well? The mechanism for Be10 production requires higher energies, usually in the form of GCR-induced protons. It was the link to paleo abundances of Be10 that kicked off the whole GCR-climate link in the first place. Calder's dam on which global warming is said to break has some leaks.
Moderator Response: [muoncounter] CLOUD Project design sheets called for 3.5 GeV positive pion beam. A separate experiment in Denmark used 580 MeV. -
muoncounter at 00:09 AM on 30 August 2011Mythic Reasoning about Climate Uncertainty
Joshua#16: "she believes "Climategate" created a "crises"" That's a great observation, although it strikes me as an extreme overreaction to events. Crisis of confidence, perhaps; crisis in the observation and understanding of the science, no. I have to wonder how the 'denizens' would react to the conclusions of the 2006 paper. Conflict with their core beliefs (greenhouse warming is real? Does not compute!) is not tolerated. -
John Hartz at 23:34 PM on 29 August 2011SkS Weekly Digest #13
@Mark Harrignton #1: Thanks for the positive feedback. I'll forward your request that SkS create a "Toon Gallery" to our Grand Poopah, John Cook.Moderator Response: [Dikran Marsupial] I think "poobah" was the word you were looking for! ;o) -
Joshua at 23:33 PM on 29 August 2011SkS Weekly Digest #13
Sad and funny at the same time. -
Joshua at 23:11 PM on 29 August 2011Mythic Reasoning about Climate Uncertainty
Re: #14 I've been reading Judith's blog quite a bit lately - and from what I've seen, her change in perspective is at least correlated to her interpretation of "Climategate." Judith has indicated that she believes "Climategate" created a "crises" in climate science - in the view of the public in general (although, interestingly, from what I've seen has yet to quantify the data that underlies her certainty about the impact of "Climategate"). My interpretation is that her view of a larger reaction to "Climategate" is more a projection (of her own reaction) - as she has stated often that "Climategate" deeply affected her own approach to the "climate community." I am sympathetic to Judith's concerns about the impact of motivated reasoning and confirmation bias in the debate about climate change; those basic psychological phenomena are fundamental attributes of the reasoning of people (scientists or otherwise) engaged in debate about controversial topics. Unfortunately, from what I've seen, ironically Judith fails to consistently apply similar scrutiny to her own reasoning processes, the reasoning of her "denizens," or the reasoning of other players in the "skeptical" blogosphere. Judith was concerned about phenomena such as "motivated reasoning" both before and after "Climategate" (even if the terminology she used to describe those phenomena evolved over time). I think that the dramatic shift in her own conclusions about the science of climate change, the related political context, and the reasoning process of people that she disagrees with, clearly lies in a shift in the "motivations” behind her own reasoning. I’m not suggesting anything particularly nefarious there; without knowing her personally it would be impossible for me to assess what lies at the root of her motivations. I think that it is “unscientific” for anyone to base conclusions about someones motivations based purely on speculation (although I will note that Judith seems unconcerned with the constant drone of many of her "denizens" attributing nefarious motivations to pretty much anyone who thinks that global warming is 90% likely to be anthropogenic). However, something fundamental changed with respect to what Judith is motivated to prove in her view of the climate change debate. As to whether “Climategate” or something else lies at the root of her shift in motivations may be a chicken/egg enigma – but perhaps the answer to that riddle could be found in “laying bare the underlying causal chain and potential approach to verification” evidenced in her reasoning process." -
Eric the Red at 23:02 PM on 29 August 2011Climate Ethics: What Can Science Tell Us?
Thanks Rob for the post and link to the Li paper. -
Eric the Red at 22:44 PM on 29 August 2011Extreme weather isn't caused by global warming
Adelady, I wholeheartedly agree. AGW does not directly cause these events, but can affect the impact due to warmer temperatures and higher humidity. -
Eric the Red at 22:33 PM on 29 August 2011Climate Sensitivity: Feedbacks Anyone?
Ice-albedo feedbacks should be included in fast-feedback sensitivity as the absorption / reflection of solar radiation is immediate. There is some indication that the high latitude albedo effects are more localized than the ice-albedo feedbacks associated with continental ice, as witnessed by local temperature changes. I agree with Sphaerica (a rarity) about the 5000 vs 7000 year distinction about the Arctic sea ice. Although the sea ice has been present for 5000 years, it has been anything but constant. (DB, I think you are confusing sea ice extent with sea ice anamoly in your Antarctic graphic). Vegetative albedo feedbacks are slow and highly variable by comparison, and when combined with the absorption feedback results in a net negative.Response:[DB] You may want to check the link...both are down. Just sayin'.
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Bob Lacatena at 22:14 PM on 29 August 2011Climate Ethics: What Can Science Tell Us?
24, Rob Painting, Thanks! -
Mark Harrigan at 20:59 PM on 29 August 2011SkS Weekly Digest #13
I love these "toons of the week". Moderators may we please have a link to all of them like there is to the graphics?? The graphics are powerful ways of communicating the message of the science but the toons are, sometimes, an even more powerful and quite "disarming" way to rebut the denialists without the aggravation and confrontation that frequently ensues. -
chris at 19:24 PM on 29 August 2011Mythic Reasoning about Climate Uncertainty
muoncounter, Dr. Curry isn't the only scientist who's scientific philosophy has changed dramatically from straightforward participation in the scientific effort to politicized (one assumes) support of science mirepresentation. The psychology associated with these transitions is rather fascinating. Craig Loehle provides another example: 20-odd years ago Loehle felt so strongly against attempts at political interference in science, and particularly the efforts at "fraud-hunting" and "auditing" that he wrote a letter to Nature on the subject. some excerpts [see Nature (1989) 338, p. 370]:"There is a danger in the controversy over fraud in science of merging the concepts of fraud and error. The call for an audit of scientific papers for error is a symptom of this trend. Fraud such as fabricating data or publishing the work of other's as one's own is of course serious, particularly when it involves assessment of drugs and other medical treatments whwre lives are at stake. But error is an inevitable part of science. The fundamental point is being missed in the current debate...."
and towards the end:"Who will review the error hunters? Who is qualified to punish whom?"
And yet Loehle spends time on a blog where the sort of "auditing" that he decried all those years ago is used to bully and harass scientists. Googling "Craig Loehle fraud", uncovers many examples of his (scientifically pretty dismal) work being used to bolster the efforts of those bellowing "fraud" against science. Dr. Loehle seems to think this is now acceptable. -
babelsguy at 18:44 PM on 29 August 2011Climate Sensitivity: The Skeptic Endgame
@Gilles, #38 Concerning the amount of carbon still available in fossil fuels... I agree that there is much less accessible carbon in the world than commonly assumed. Some IPCC scenarios may well overstate the possible emissions. Still, I once calculated how much fossil carbon there is, based on studies by the Energy Watch Group (EWG) (http://www.energywatchgroup.org/) and found that together with the other CO2 sources (e.g. land use change, cattle), there is still easily enough Carbon in the ground to ruin the planet. To determine this, I researched the "carbon emission limit" that will keep us on the "safe" side. According to [Meinshausen et al. 2009] this is 1000 billion tons of CO2 equivalent between 2000 and 2050. They estimate that 25% of this are already emitted, so there remain 750 billion tons (Gt). Of this, about 40% come from other sources than fossil fuel burning: land use change, cattle, paddy fields, nitrogen dioxyde fertilizers etc. So there remain 450 billions tons CO2 to come from fossil fuel burning. To normalize these to pure carbon equivalent for easier comparison with fuel carbon content, I divide by 3.67 (the molecular weight ratio between 2 oxygen atoms and one carbon atom) and get ~123 Gt/C as the upper limit to what we can still emit from fossil fuels. Now comes a little eyeballing stunt: Looking at the respective coal and oil production curves from the EWG studies (and researching for the natural gas ones elsewhere) and multiplying the readings for 2025 and 2050 by approximate carbon content and summing these numbers, I come up with possible emissions of 7.403 Gt/C in 2025 and 5.421 Gt/C in 2050. Now even if I multiplied the lower number for 2050 with the remaining years up to 2050 (38), I get emissions of ~206 Gt/C - far above the limit. Of course, fossil fuel scarcity will not force us to drop to this 2050 level tomorrow - in a "peak fossils" scenario, production will follow a nice right-side-of-a-bell-curve trajectory, so actual accumulated emissions could be much higher than 200 Gt/C - shooting this planet to hell. Oh, and by the way... [Meinshausen et al. 2009] give a probability of 25% that 1000 Gt/CO2 until 2050 will *still* produce warming above the magic "safe" limit of 2°. Would you use an airplane with 25% probability to crash? No? And we are talking about a whole planet here, not just an airplane! -
Kooiti Masuda at 18:21 PM on 29 August 2011Climate Sensitivity: Feedbacks Anyone?
Ice-albedo feedback due to sea ice and snow cover is (in principle) included in fast-feedback sensitivity or "Charney sensitivity". Ice-albedo feedback due to continental ice sheets and albedo feedback due to vegetation are considered as slow feedbacks. -
Dikran Marsupial at 17:41 PM on 29 August 2011Settled Science - Humans are Raising CO2 Levels
Skeptical Wombat If Salby's answer to your question were to be "if the Industrial Revolution had not occurred then CO2 levels would still have gone up by 95% of the amount by which they did increase" he would be very wrong. I suspect what Salby meant was that if you look at the additional CO2 that has been added since the industrial revolution, then only 5% of those molecules will be of directly anthropogenic origin. This is basically true and completely consistent with the cause of the rise being 100% anthropogenic. I know that sounds rather counterintuituve, but it is true. The reason that only about 5% of the molecules are of directly anthropogenic origin is that there is a vast exchange flux that each year exchanges about 20% of atmospheric CO2 with CO2 from the surface oceans or from terestrial biosphere. However this is a straight exchange and hence doesn't alter the atmospheric CO2 levels, but it does mean that anthropogenic CO2 is replaced by "natural" CO2. The action of the exchange flux has confused many, especially leading to the "residence time" argument discussed on another thread. This is well known to those who study the carbon cycle. I am currently writing an advanced version of the "residence time" rebuttal, and it will include a simple model that explains the 5% figure (and I'll include an analogy for those that don't like differential equations). BTW, the sinks and sources are not undiscovered; the figures given in the IPCC WG1 report are consistent with an anthropogenic cause of the rise and there being only a small fraction of anthropogenic CO2 comprising the excess. -
adelady at 14:59 PM on 29 August 2011Extreme weather isn't caused by global warming
"I suppose what I am getting at at what stage can we start safely matching extreme weather events to AGW?" One thing you can do is look at the average increase in humidity due to raised temperatures. When we say that there's 4% more moisture aloft than before, you can get hold of the weather service's measurements of precipitation leading to floods and other damage. Then do some calculations with and without that 4%. What height would the floodwater have reached if there had been x% less water flowing into the system? The big issue here of course is that 4% is the global average increase. Choosing - let alone justifying - a more suitable number for a specific time and place is much harder. But this sort of calculation can be illustrative if not definitive. Without a 4% increase in humidity, floodwaters may only have reached 2 streets from the riverbank rather than the ... distance they did. Not terribly scientific, but may provoke thought. And much more useful for real life. AGW may not cause certain events directly, but it can worsen the impact of those that do occur. -
Rob Painting at 14:55 PM on 29 August 2011Climate Ethics: What Can Science Tell Us?
Scadden P @ 20 & Dan Bailey (moderator comment) @ 15 - There has been a dramatic increase in ENSO severity during the last century. See Gergis & Fowler (2006) "Although extreme events are seen throughout the 478-year reconstruction, 43% of the extreme ENSO events noted since A.D. 1525 occur during the 20th century, with an obvious bias towards enhanced El Nino conditions in recent decades. Of the total number of extreme event years reconstructed, 30% of all reconstructed ENSO event years occur post-1940 alone suggesting that recent ENSO variability appears anomalous in the context of the past five centuries." The frequency and intensity of ENSO appears to be tied to the mean state of the tropical Pacific. When equatorial waters in the central and eastern Pacific are warm, frequency and intensity are increased. When cooler, activity diminishes, although there can be huge swings in intensity during these cooler periods. See Li (2011)
As far as future projections are concerned, that's unsettled for now. Climate models seem split on whether we'll see an increase/decrease in ENSO activity. See Vecchi & Wittenburg (2009) and Collins (2010)
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Bern at 14:55 PM on 29 August 2011Mythic Reasoning about Climate Uncertainty
muoncounter: that is indeed extraordinary. I wonder if Curry offers extraordinary evidence to explain her change of mind on global warming? If not, then it certainly leaves one wondering as to how & why someone can so completely change their public statements on an issue. As you've suggested, in politics it's all too common, and driven by a motivation to gain or retain elected office. Elsewhere, the motivation is generally ideological, religious, or financial (or a combination thereof). -
skywatcher at 13:53 PM on 29 August 2011Climate Sensitivity: Feedbacks Anyone?
Excellent article. Contrarians often comfort themselves with by suggesting that climate sensitivity is about 1C per doubling and that you can only get to higher sensitivities through "hypothesised positive feedbacks". They don't appreciate the physical reality of the feedbacks, and that they are not only real, present and active today, but also absolutely necessary to explain past climate change. You cannot explain climate with negative net feedbacks. Ice-albedo feedback seems a very appropriate topic as we head below 5 million sq km IJIS extent in Arctic for only the 4th time, which is the 4th time in 5 years. Late summer Arctic sea ice volume is also desperately low, and with futher reduction, extent loss is certain and so will be a further increase in the albedo feedback. -
scaddenp at 13:51 PM on 29 August 2011Extreme weather isn't caused by global warming
"I suppose what I am getting at at what stage can we start safely matching extreme weather events to AGW?" Doing this scientifically requires matching observations of weather to predictions from the climate models. As I understand it, only really disruptions to the hydrological cycle (drought and extreme precipitation events) are settled science within the predictions. Hurricanes are not. AR4 discussed extreme precipitation events but there was not really a long enough record to be making strong statements. Droughts will wax and wane in cycles but the pattern of drought is consistent with predictions. I dont believe you can link any single weather event to AGW - only trends in frequency and/or intensity. -
scaddenp at 13:44 PM on 29 August 2011Climate Ethics: What Can Science Tell Us?
This discussion belongs here. I have commented there. -
Stevo at 13:22 PM on 29 August 2011Climate Ethics: What Can Science Tell Us?
So is it safe to work on the principle that at the moment the indications are that the ENSO may be more intense but not neccessarily more frequent? Also it seems that ENSO is claimed to be the driver of intense weather events in eastern North America and Africa. Is that true? I suppose what I am getting at at what stage can we start safely matching extreme weather events to AGW? -
Bob Lacatena at 12:56 PM on 29 August 2011Climate Sensitivity: Feedbacks Anyone?
12, Camburn, Your own link belies your statement, and you provide no other supporting links. Michael Sweet said (correctly):For the last 5,000 years (or more) the Arctic sea ice has been a constant ice sheet over most of the Arctic Ocean.
Your link said:”The climate in the northern regions has never been milder since the last Ice Age than it was about 6000-7000 years ago. We still don’t know whether the Arctic Ocean was completely ice free, but there was more open water in the area north of Greenland than there is today,” says Astrid Lyså, a geologist and researcher at the Geological Survey of Norway (NGU).
See the difference? 5,000 years versus 6,000-7,000? Coincidentally, temperatures have been dropping for the last 7,000 years, which marked the Holocene Climactic Optimum, when temperatures were approximately roughly equal to what they are today. So evidence that the Arctic had less ice 7,000 years ago is further evidence of current warming, what that warming will do, and the fact that warming above and beyond that will have unheard of effects. It's all consistent... all except your personal interpretation of it, that is. -
Sceptical Wombat at 12:48 PM on 29 August 2011Settled Science - Humans are Raising CO2 Levels
The question I would ask Salby is what he means by saying that anthropogenic emissions only account or 5% of the increase in CO2. Presumably he means that if the Industrial Revolution had not occurred then CO2 levels would still have gone up by 95% of the amount by which they did increase. That leaves the question of where the CO2 we emitted has gone and where the increase in CO2 we observe came from. If we assume that 97.5% of the CO2 we emitted has been soaked up by negative feed back we must assume that the same would be true of the CO2 from the natural source that is responsible for the observed increase. In other words there is an as yet undiscovered source which is emitting 19 times as much as we are emitting and an undiscovered sink which increases proportionately to increases in CO2 in the atmosphere and is currently absorbing a 19.5 times the amount we are emitting. That looks like a very big source and a very big sink - should be easy to find. -
Camburn at 12:39 PM on 29 August 2011Climate Sensitivity: Feedbacks Anyone?
michael sweet@4: Your point about Arctic Ice is not correct. Study of north shores of Greenland Paleo study of Greenland North Beach Holland also had a very extensive study on Arctic Ice, but it seems the url to the paper is no longer viable. There are also paleo studies of bow head whales that dispute that the Arctic Ice has been stable for the past 7,000 years. In fact, it has flucuated dramatically. -
SteveS at 12:32 PM on 29 August 2011Climate Ethics: What Can Science Tell Us?
Sphaerica@18: While this paper (ENSO-Scale Variability in the Eocene Greenhouse Recorded by Fossil Bivalves and Wood from Antarctic) doesn't seem to say anything about the intensity of ENSO, it does seem to indicate that the frequency will be unchanged by warming temperatures. Also a blurb here. -
scaddenp at 12:26 PM on 29 August 2011Climate Ethics: What Can Science Tell Us?
Also, Boer et al 2004. "Three streams of evidence, namely simulations with coupled models, feedback analysis in the tropical Pacific, and observation-based paleoclimate reconstructions, all support the expectation of a future mean El Nin˜o-like temperature response to the positive radiative forcing resulting from a continued increase in atmospheric greenhouse gas concentrations." However, a multi-model study van Oldenborgh et al 2005 isnt so definite, and Guilyardi 2005 concluded "There are no clear indications of an El Nino frequency change with increased GHG." This seems to be repeated in later papers. I would say this is still unsettled science unless someone has some newer evidence.Moderator Response: [mc] fixed closing link tag -
muoncounter at 10:41 AM on 29 August 2011Climate Ethics: What Can Science Tell Us?
Sphaerica#16: "unable to find any papers (yet) that explicitly say that climate change will affect (increase) ENSO events." An oldie-but-a-goodie: Timmermann 1999 Increased El Nino frequency in a climate model forced by future greenhouse warming The tropical Pacific climate system is thus predicted to undergo strong changes if emissions of greenhouse gases continue to increase. The climatic effects will be threefold. First, the mean climate in the tropical Pacific region will change towards a state corresponding to present-day El Nino conditions. It is therefore likely that events typical of El Nino will also become more frequent. Second, a stronger interannual variability will be superimposed on the changes in the mean state, so year-to-year variations may become more extreme under enhanced greenhouse conditions. Third, the interannual variability will be more strongly skewed, with strong cold events (relative to the warmer mean state) becoming more frequent. That last one sounds like a description of the last couple of winters. -
Tom Curtis at 10:28 AM on 29 August 2011Temp record is unreliable
econ101lab @215, your source appears to suggest that GISSTEMP temperatures are arrived at by simply cutting and pasting some other temperature from within a 1200 km radius. That is simply false. Rather, all stations within a 1200 km radius (over land) are given a weighting depending on their distance from center of the cell. The weighting is (1200 - distance in km from the center of the cell)/1200. All stations within range are then used to give a weighted average for the cell. The procedure is explained in detail in Averages and Anomalies part 1B. Very importantly, the HadCRUT is calculated by taking a simple mean of all stations within a cell, with no extrapolation. This is important because HadCRUT and GissTemp show effectively the same trend if you exclude polar regions, ie, the regions HadCRUT does not cover due to lack of surface stations. That shows the GissTemp procedure does not introduce a spurious trend. The comparison between GistTemp and DMI in the Arctic shows their extrapolation does not introduce a spurious trend in the Arctic either. Beyond that I heartily recommend you read the links provided by DB (inline comment @216) and KR @219. You should also add Ned's article on Assessing global surface temperature reconstructions to your reading. Finally, climate science is a diverse beast. Some parts of it are as well established as any other scientific theory, while other parts are relatively tenuous. Very little of it is as tenuous as even the best established theorems of macro-economics, and certainly the recent temperature record is not open to serious dispute. Is it settled science? Well researchers in the field will always try to improve their methods and eliminate assumptions that may have led them astray. But the results are sufficiently well established that people outside that narrow field can take the current results as being settled for the purposes of any further research they need to do. -
John Hartz at 10:10 AM on 29 August 2011Mythic Reasoning about Climate Uncertainty
SkS should create a button for its series of articles about Dr. Curry's pronouncements -- "Curry's Curios" perhaps. -
Bob Lacatena at 10:09 AM on 29 August 2011Climate Ethics: What Can Science Tell Us?
15, apiratelooksat50, FYI, all of those references I supplied are vague and inconclusive. My own opinion at the moment would be that while a climate-change-enhances-ENSO connection seems logical, there is as yet no substantive evidence of it.Response:[DB] Bob, Rob Painting is pretty up to speed on studies ENSO-related. Perhaps Rob could be a resource on this.
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Bob Lacatena at 10:05 AM on 29 August 2011Climate Ethics: What Can Science Tell Us?
15, apiratelooksat50, AR4 has this: 3.6.2 El Niño-Southern Oscillation and Tropical/Extratropical Interactions With this statement:Extremes of the hydrological cycle such as floods and droughts are common with ENSO and are apt to be enhanced with global warming (Trenberth et al., 2003). For example, the modest 2002–2003 El Niño was associated with a drought in Australia, made much worse by record-breaking heat (Nicholls, 2004; and see Section 3.8.4, Box 3.6). Thus, whether observed changes in ENSO behaviour are physically linked to global climate change is a research question of great importance.
Also: ENSO Amplitude Change in Observation and Coupled Models [ZHANG Qiong1 (张 琼), GUAN Yue1,3 (关 月), and YANG Haijun, 2007] and: Shifts in ENSO coupling processes under global warming [Sjoukje Philip and Geert Jan van Oldenborgh, 2006] -
Philippe Chantreau at 09:54 AM on 29 August 2011Temp record is unreliable
econ101lab, you stated you like to look at a variety of sources and check. That would be the right attitude. However, from what you wrote so far, I see little variety in the type of sources you look at and you are asking others to check for you. How come? In one of your posts, you say "if true." That suggests you have not actually looked into whether or not it is. As for the CERN results, one would be hard pressed to point exactly what words or numbers from Kirkby et al can be used to support the flashy headlines that you deemed appropriate to reproduce here. Others have supplied the links you need to check into that but, once again, I am surprised that you had not already found these on your own. The kind of skeptical attitude you claim would have allowed you to find these sources in only a few minutes of search engine use. -
scaddenp at 09:52 AM on 29 August 2011GHG emission mitigation solutions - a challenge for the Right?
Eric, I defined "effective" in second to last paragraph of the article. I tightened up the definition to get rid of suggestions that you can do much good with simple efficiency gains. Efficiency alone (defining efficiency as doing same but with less energy) cannot produce the required reduction and here is why. Firstly, people wherever they are need heating/cooling/lighting, all subject to carnot efficiency limits. Moving people around in the job economy doesn't change that unless you are moving a significant number of people from inside to outside. Moving goods is quite efficient - accounting for only about 20% of liquid FF. If you eliminated that completely its only about 10kwh/p/d. Moving people is the problem as you said. It is the cheapness of transport and economies of scale that cause centralizing of industry. Likewise, people will drive to malls with free parking because the economies of scale making prices cheaper and requires less walking. It's economics, not a local government conspiracy. I also find your comments of local government being in cahoots with developers for dense housing and service extensions bazaar. Services cost. Dense housing is good use of land and far more efficient for delivery of services. Our local government hate extending services and since the properties pay for it, you find offgrid installations happening where it is cheaper to go off grid rather than connect to services. Revenue must match service cost. Surely your local government is not dividend-paying companies that are trying to increase revenue to make a profit? Inefficient cars and houses are a problem but surely it isn't the libertarian way to require minimum fuel economy standard and "passivhaus"-type standards that other more left-leaning countries demand? However, I would also point out that increasing transport efficiency to 100% would save you only 52kwh/p/d. Eliminating all space-heating costs for houses would save another 7kwh/p/d. What's your alternative to local zoning? I'll bet it isn't putting up with pig farm or 10 storey factory on your back fence. Fight each and every development through the courts to arbitrate of respective rights of each land owner? "There are really no limits to efficiency". Yes, there really are. Physics is not an arbitrary limit. All this effort on efficiency is about avoiding the actual effective way to reduce GHG emissions - changing the source of energy. I quite agree that you cant have the same society with a reduction from 200 to 60 by efficiency alone. You can though if change the price equation so it makes sense to invest in whatever is next-cheapest option for energy generation other than FF. The left can do with simple ban on new FF generation, no taxes, no admin cost. However, the right hates that so what is your way? You are extremely concerned about rights of people holding shares in coal. How come you aren't also concerned about the rights of those affected by GHG emission? This is the core of issue. -
Bob Lacatena at 09:51 AM on 29 August 2011Climate Ethics: What Can Science Tell Us?
15, apiratelooksat50, I noticed the same thing. I've been unable to find any papers (yet) that explicitly say that climate change will affect (increase) ENSO events. I did find the following statements attributed to Trenberth:“There have been changes in the El Niño-La Niña cycle since the 1970s. It’s a complex cycle but the associated droughts, flooding and other manifestations have been stronger over the last 30 to 40 years,” Trenberth told Tierramérica. Since climate change has fundamentally altered the global climate system, trapping more heat and about four percent more water vapour in the atmosphere, it is reasonable to conclude it has affected the ENSO cycle. “It would be surprising if there wasn’t an effect,” Trenberth said.
I'll keep looking for actual scientific studies on the subject. If anyone else knows of any, it would be appreciated. -
bibasir at 09:21 AM on 29 August 2011Mythic Reasoning about Climate Uncertainty
I continue to be disappointed in how little science is presented in Dr. Curry's pronouncements. She also fails to point out that uncertainty cuts both ways. -
otter17 at 09:12 AM on 29 August 2011GHG emission mitigation solutions - a challenge for the Right?
Camburn @ 109 "What subsidies are you talking about regarding FF?" There was a bit of a political buzz for a while in the USA about repealing oil subsidies. http://thinkprogress.org/yglesias/2010/02/01/196008/obama-vs-dirty-energy-subsidies/ http://thinkprogress.org/romm/2011/05/22/208130/why-oil-companies-dont-need-tax-subsidies/ Essentially, what the wind industry wants is a level playing field. Here is a pretty good factsheet summary of the subsidy playing field. http://www.awea.org/_cs_upload/blog/5400_1.pdf Really, the fossil fuel subsidies aren't incredibly large. Repealing those subsidies and improving the renewable subsidies would probably not be the magic bullet. -
muoncounter at 08:44 AM on 29 August 2011Mythic Reasoning about Climate Uncertainty
chris#9: That is a stunning find; the paper is indeed available in pdf from your link - thanks! It is quite a difference from the current party line, which includes:And finally, I’m sure you knew it had to be coming: Irene’s got a middle name, and it’s Global Warming The quote is from Bill McKibben, cited in a post at Collide-a-Scape. Apparently Kevin Trenberth’s reversal of the null hypothesis has taken hold in certain segments.
The 2006 paper quotes Trenberth as inspiration: Trenberth (2005) published a commentary in Science raising the issue as to whether the increase in North Atlantic hurricane activity since 1995 could be attributed to global warming. This paper motivated us to begin looking at global hurricane data. Here is Curry's own reversal of the null hypothesis: while there are uncertainties and heterogeneities in the global hurricane dataset, the magnitude of the trend identified by WHCC is sufficiently large that the null hypothesis must be rejected based upon the currently documented uncertainties in the dataset. Acknowledgments go to Trenberth, Emmanuel and others - most notably the arch-enemy Joe Romm; a far cry from thanking the denizens of ClimateEtc for their 'contributions.' I believe this is known in political circles as a flip-flop. -
apiratelooksat50 at 08:43 AM on 29 August 2011Climate Ethics: What Can Science Tell Us?
Badger at 5 I followed your link and read the article. It refers to the well documented natural phenomena of El Nino and La Nina, and then makes a reference to AGW having an effect on these cycles. However, it does not provide any background data to support that claim. Is there any available? -
KeenOn350 at 08:33 AM on 29 August 2011Mythic Reasoning about Climate Uncertainty
Seems to me that Curry's latest is simply an erudite game with words, "full of sound and fury, Signifying nothing." DaveW -
chris at 08:18 AM on 29 August 2011Mythic Reasoning about Climate Uncertainty
The change in Dr. Curry's approach to science in a few short years is fascinating. I was very impressed with the first paper of hers I read which is a sort of forensic/logical dissection of the arguments used by various people including "well-known global warming deniers" (her phrase) who set about muddying the interpretations on her earlier study of increased contemporary hurricane intensity. She comes down firmly on the side of the hypothesis (incorporated in the title of her paper just below), and describes the problems wth media and World Wide Web in muddying the debate. J. A. Curry, P. J. Webster, AND G. J. Holland (2006) Mixing politics and science in testing the hypothesis that greenhouse warming is causing a global increase in hurricane intensity Bull. Am. Meteor. Soc. Aug 2006, 1025-1037 link to paper (hope it's freely accesible) The abstract of the paper is fascinating as it indicates a startling volte face in her subsequent approach to science, science misrepresentation, and uncertainty:abstract: This complex hypothesis has been muddied frequently in recent public debate, yet can be clarified by laying bare the underlying causal chain and potential approach to verification.
Since now she's actively promoting "muddying" of the science in "public debate". And whereas (as muoncounter has described above) Curry and Webster quibble over the phrase from the IPCC report that “Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations,” (apparently forgetting that this phrase only has meaning in the context of the large amount of evidence presented in the associated reports), these two (Curry and Webster) were careful to point out in the hurricane/hypothesis paper that:"These simulations and analyses provide solid evidence that the global surface temperature trend since 1970 (including the trend in tropical SSTs) cannot be reproduced in climate models without the inclusion of anthropogenic greenhouse gases."
...and addressing the null hypothesis that: "Recent trends in tropical surface temperatures are not a response to greenhouse warming.", Curry and Webster come down firmly on the sie of rejecting the null hypothesis:"Hence, the null hypothesis is rejected because the trend in tropical SST cannot be explained by natural internal variability and/or volcanic eruptions or solar variability, and the observed trend is consistent with model simulations associated with forcing from greenhouse gases."
What on earth happened? From a careful and logical analysis of the evidence that bears on an aspect of climate science including cautionary accounts about the problems of science denialism and Web- and media-based misrepresentation....to a complete switch of viewpoint in which Web-based misrepresentation and promotion of nonsensical faux-explanations of otherwise rather well-supported science are actively encouraged....all in the space of a few years... -
muoncounter at 08:13 AM on 29 August 2011Mythic Reasoning about Climate Uncertainty
AB#7: "I thought that had been done already." Spend some quality time browsing the comments on these misinformer sites and you'll find that folks there do not inhabit the same reality as the rest of us. In their world, warming stopped in '98, the warmest year was '34, the Arctic is recovering nicely, etc. There's even a new meme starting today: Hurricanes aren't linked to warming - because Irene didn't get to cat 4 or 5 and 'weakened' as it moved north. The fact that some can make such statements before the rain stops and the damage assessment is done is repugnant to anyone who has ever lived through such a storm. When a serious scientist makes a statement like 'we need evidenced-based analysis,' you have to wonder if they haven't been in that world so long they would no longer recognize ours. -
PrezMulkeyUnity at 07:44 AM on 29 August 2011Republican Presidential Candidates vs. Climate Science
In order for these politicians to have credibility with their anti-science arguments, they must damage or dismiss the credibility of our most trusted scientific institutions. I have seen this strategy before. I recently had the displeasure of sharing a podium with Willie Soon. Soon began his talk with ad hominem attacks on Holdren, Cicerone, and Lubchenco. His statements about the first two implied that they had an ulterior motive and were in collusion. The logical extension of his remarks is that there is a vast conspiracy at the top to control U.S. science. For Lubchenco, his remarks were more personal, suggesting that she knows that she is propagating falsehoods about ocean acidification and that she is seeking personal gain by doing so. I suspected that Soon had been coached, and it seems likely that he is well rewarded for his efforts. In contrast, my colleague and I from the University of Idaho were at the symposium to present the view of legitimate science, and we were certainly not well paid. Soon's attacks and bogus science were well received by an audience full of partisans, most of whom held advanced degrees. We should be deeply concerned with the fact that leading presidential candidates have assailed the credibility of our best scientific institutions. As reviewed by the Union of Concerned Scientists, the list of organizations and academies endorsing the basic tenants of AGW is exhaustive
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