Arguments
Recent Comments
Prev 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 Next
Comments 58201 to 58250:
-
scaddenp at 07:16 AM on 31 May 2012It hasn't warmed since 1998
Also missing is the other important question. Given the strong internal variation, what is the shortest time period over which the predicted warming trend could be detected? Estimates are somewhere around 17-20 years unless you strip out some of the known natural variability like Foster and Rahmstorf did. So your statement "According to the latest HadCRUT4 data, there is no statistically significant increase in temperature (0.083C/dec +/-0.172C/dec)" applies to which period exactly? -
bratisla at 05:49 AM on 31 May 2012In Search Of: Himalayan Ice Loss
Just a quick and not very significant correction : the main author of the Nature GRACE paper is Thomas Jacob, not Jacobs. As for the discrepancy, after some discussion with him it is still unclear - he assured me it cannot come from the crust depth correction, and this is believable since they were able to clean the signal from post-glacial rebound effects. Maybe it's because they left out areas with less than 100 km² of ice ? -
Composer99 at 04:40 AM on 31 May 20122012 SkS Weekly Digest #21
North Carolina is apparently channeling the (potentially apocryphal) spirit of Canute (without the subsequent humility). -
CBDunkerson at 04:34 AM on 31 May 2012IEA CO2 Emissions Update 2011 - the Good News and the Bad
The IEA 'World Energy Outlook 2011' from which the CO2 figures above are derived also predicts a coming 'golden age of gas'. Basically, hydraulic fracturing has increased the amount of cheap natural gas available to such an extent that grid electricity prices have started coming down... due both to switchover from coal to natural gas AND falling coal prices as demand is taken away by gas. So, the 'golden age' introduced by the 'new technology' of fracking could reverse the long trend of rising fossil fuel electricity costs... just as solar power was on the verge of reaching widespread grid parity. Most of the 'new technologies' for extracting hard to get at fossil fuels come with significantly higher price tags that would have let solar overtake them... but not so fracking. There are large deposits of shale gas all around the world and now we have an inexpensive way to get at them. Until now I thought solar grid parity was going to set a limit on CO2 accumulations. Now it seems like we're going to have to hope for some unknown new technology breakthrough, or responsible global political leadership (ha!). Otherwise the limit will be set by global warming itself in a hundred years or so when people finally respond to the increasing severity of the problem. Running out of cheap fossil fuels seems like it is off the table for decades to come... and that's very very bad news. -
arch stanton at 03:51 AM on 31 May 2012In Search Of: Himalayan Ice Loss
Thank you mspelto and Daniel Bailey for a very clear explanation of the situation. Unfortunatly, your explanation has lots of words and way too many references to appeal to some of the folks that frequent some of the over-amped blogs out there which thrive on cherry picking and quote mining. For the benefit of those that may prefer their arguments to be more concise, sensational and to rely less on science and math, please allow me to present the following “proof” of global warming: Mount Everest West Ridge – not enough snow to climb - May 15, 2012“But, Anker notes, “In 1963 they were in knee-deep snow in the Hornbein Couloir. We would have had blue ice and then two pitches where it was completely melted out.”
< /distilled cherries>Moderator Response: [DB] Thank you, Arch. This post will form the basis for the Advanced Rebuttal to the climate myth "Himalayan glaciers are growing". The Basic and Intermediate versions of this post will then be drafted as soon as time permits. -
Rob Honeycutt at 03:06 AM on 31 May 2012Models are unreliable
Ben Santer has an interesting lecture where he discusses climate modeling HERE. Santer states that no model is perfect, they're good but not perfect. He says that some models are better than other models, but ensembles of the models is better than any given model. And they also find that ensemble models that are weighted for the better individual models perform even better than that. And you have to realize, the models are not being put out there without checking them against empirical results. They, in fact, are tested against actual results, but as Dikran says, it takes a long time to test the models against the broad, long term climatic response to forcing. What I think is going on in the media and the blogs is, it's a meme that plays on people's lack of understanding of a complex science. It's the "hey, they can't even predict the weather next week" idea, which is a completely false analogy. So, people get the idea that climate change is all based on models and models don't even work. It's the mother of all red herrings in the climate debate.Moderator Response: TC: I think Clyde has more than sufficient responses to his comments now. Any further responses before he responds would by "dogpiling", and hence in contravention of the comments policy. In order to to avoid overwhelming Clyde with weight of respondents rather than weight of argument, I also request that only Bob Loblaw and Jim Eager respond to his future posts, unless they wish to deffer to some other person. -
Bernard J. at 00:46 AM on 31 May 2012New research from last week 21/2012
I must say, I am really enjoying the convenience of having these nuggets collated here in one weekly thread, when I spread myself too thin with other things to find such papers for myself. I've thanked you before, but I'll say thanks again. On a completely off-topic point, and acknowledging that it is not really a part of SkS's remit, might it be possible to post a small thread about the impending transit of Venus? It'll be the last one that anyone alive today will ever see, and there's a lot of astronomical history attached - I reckon that it would be nice to draw attention to it for people to 'appreciate', in case they'd like to observe the event itself. -
Dikran Marsupial at 00:32 AM on 31 May 2012CO2 has a short residence time
Martin, Abell & Braselton ("Modern Differential Equations", Saunders College Publishing, 1996) on page 72, say that a first order linear d.e. can be written in the form dy/dx + p(x)y = q(x) The d.e. defining the one-box model in my paper dC/dt = F_i^0 - k_eC - F_e^0 is of that form, where y = C x = t p(x) = k_e = constant q(x) = F_i^0 - F_e^0 = constant As the one box model exhibits an adjustment time that it much longer than its residence time, but is described by a linear d.e., then AFAICS this establishes that the conjecture is false. Non-linearity is not required for the adjustment time to be longer than the residence time. -
Bernard J. at 00:25 AM on 31 May 2012IEA CO2 Emissions Update 2011 - the Good News and the Bad
Using the data available at Mikeh1's link at #7, and using the emissions value for 2012, one can roughly calculate the number of tons of carbon per person remaining to be burned before the planet reaches a total of one trillion tons emitted. If one assumes that the carbon will be allocated only to the 7 billion people currently living, we can burn a whisker over 1428 tons each before we need to stop. For the 750 billion ton limit the figure is 1071 tons. If we share the carbon equally amongst 8 billion people the figures are 1250 and 937 tones respectively, and if we generously allocate the carbon to 9 billion people it is 1111 and 833 tons of carbon per person, respectively. Consider how much carbon the average Westerner currently uses per annum - a round figure of 25 tons or so. Consider the future generations who would be necessarily excluded from using carbon in this manner. Consider how little effort we have made thus far to wean ourselves from our carbon addiction. Perhaps we should all be given carbon ration cards, and told to live our lives with the strict proviso that we get not a gram more than we're allocated, unless we buy it legitimately from others. This would bring cap-and-trade right to the front doorstep - now wouldn't that get people off their butts to reorganise how they energise their lifestyles? Sadly, for many, the answer is "probably not". -
DSL at 00:02 AM on 31 May 2012Models are unreliable
And, finally, Clyde, remember that any claim you make contrary to these computer models must be based on a model itself. It may be your intuition, or it may be someone else's computer model, but it's still a model. Unless, of course, you give voice to thoughts which have no rational origin, and I don't think you'd admit to that (or your admission wouldn't mean anything if it were true). Thus, just saying "models suck" is not good enough. You need to be able to defend your own model (or the model you currently accept) against the IPCC's model set, or you're just barking loudly without any teeth. -
DSL at 23:53 PM on 30 May 2012It hasn't warmed since 1998
Peter42, if your basic question is "what would convince me that non-significant or no warming is taking place," then the answer is "non-significant or no warming taking place." If, instead, you're asking about AGW fundamentals, then I'd have to be provided with a comprehensive physical model that did not allow CO2/H20/et al. to absorb and emit within the range at which the sun-warmed surface of the Earth emits, and one which did not allow cooler "objects" to radiate toward warmer "objects." Absent that alternative model, anthropogenic global warming must be taking place. Is some cooling factor countering the warming? Perhaps, but that doesn't mean the GHG factor has stopped doing its thing. If insolation drops and aerosols increase, both providing overwhelming cooling effects, does that mean that AGW is not occurring? No. The warming--or, as some semantic trolls like to have it, "the slowing of cooling"--is still occurring, even when the temperature is trending down. That's what Foster & Rahmstorf (2011) partially addresses. Strip away the major cooling/warming factors (solar, ENSO, volcanic) other than GHG, and what do you have left? -
Jim Eager at 23:28 PM on 30 May 2012Models are unreliable
Clyde wrote: "I've never seen any credit given to computer modelers." How would you know this? What, exactly, is your definition of a computer modeler? What is your expertise in determining who is a competent computer modeler? "Would you want heart surgery done by a doctor who has performed say 100 successful operations or by a doctor who has used a computer to project/predict how to do the operation?" Your analogy actually better applies to you. It seems you would trust the expert modeler who has no understanding of the physical climate than the climatologists who actually study the real climate. Where do you think climatologists working with computer modeling learn enough about the the physics and chemistry of the real climate to model it? "Would you bet your life on the future global warming projections/predictions coming from computers?" Yes, I would and I am. Would you bet yours, or more telling, your children's and your grandchildren's lives on going forward with business as usual without understanding the possible impacts of tampering with the atmosphere and greenhouse effect and ocean chemistry and without bounding the probability of those impacts by modeling them? "Do you want me to post the links to the failed predictions/projections?" Do you mean failures like successfully predicting... ... that global mean temperature would warm, by about how fast, and by about how much ... the rising of the tropopause and the effective radiating altitude ... that the troposphere would warm while the stratosphere would cool ... that night time surface temperatures would increase more than daytime temperatures ... that winter surface temperatures would increase more than summer temperatures ... that higher latitudes would warm faster than temperate and equatorial latitudes (polar amplification) ... that the Arctic would warm faster than the Antarctic because the two poles are physically and geographically quite different ... the magnitude (~0.3 C) and duration (~two years) of the aerosol cooling caused by the 1991 Mt. Pinatubo eruption ... that modeled hindcasts for Last Glacial Maximum sea surface temperatures was inconsistent with the paleo evidence, and then better paleo evidence showed that the models were right ... a trend significantly different and differently signed from the UAH satellite temperature record, and then a bug was found in the UAH satellite data ... a tropospheric temperature trend significantly different and differently signed from the balloon radiosond temperature record, and then it was found that the thermometers used on the balloons were not properly shielded from direct sunlight ... the ~4% increase in absolute humidity as the atmosphere warms (water vapor feedback) ... the increase in both number and intensity of record high temperature events ... the increase in both drought intensity and intense precipitation events ... the response of southern ocean winds to the ozone hole ... the northward expansion of Hadley cell circulation ... the expanded range of hurricanes and tropical cyclones, poleward movement of storm tracks, and the increase in average cyclone & hurricane energy intensity It's "failures" like these that give me confidence that the models are useful. Not that they are right, but useful. -
Composer99 at 22:19 PM on 30 May 2012It hasn't warmed since 1998
Re: Peter42's comment #199: what credible data and information over what period would you require (rather than simply some authoritative opinion), for you to change your mind? I'm not sufficiently technically literate to avoid relying on the expert authority. However, as I noted upthread there are two fundamental elements which at the present time unequivocally demonstrate global warming: - the ongoing accumulation of heat in the ocean - the ongoing measured positive energy imbalance at top-of-atmosphere I expect either or both of these would have to be unequivocally trending negative, over a statistically significant period, before I would expect to see a major shift in position. -
Chookmustard at 22:16 PM on 30 May 20122012 SkS Weekly Digest #21
Hi guys, funglestrumpet makes some good points! I was reading a link from Andrew Bolts blog a few weeks ago (don't judge me I'm trying to avoid going there) that was to a paper by some Danes about sun spot activety, particularly a negative temperature trend between a solar cycle length and temps in the next cycle. Apparently that may mean a temperature drop coming up soon! The paper is on Science Direct website and attributed to The Journal of Atmospheric and Solar Terrestrial Physics. it has a thank you note at the end to David Archibold which made me check here for debunked myths/ ideas. a Myth Monday debunk perhaps? Cheers Chook -
Martin A at 22:13 PM on 30 May 2012CO2 has a short residence time
Dikran M: Commiserations on the exam marking - I can't imagine it's much fun. Thank you for the comments - I'll study them carefully and try to do some calculations with the data. I came across the paper H. Rodhe + A Björkström "Some consequences of non-proportionality between fluxes and reservoir contents in natural systems" (Tellus(1979),31, 269-278) which specifically studies nonlinear equilibrium. It reinforces my conjecture that nonlinearity is necessary for (residence)/(adjustment)< 1. -
mikeh1 at 21:38 PM on 30 May 2012IEA CO2 Emissions Update 2011 - the Good News and the Bad
Re Figure 3 You can track progress to the 750 Gt here. The figures on this site are the estimated cumulative emissions from fossil fuel use, cement production and land-use change since industrialization began. At current rates of emission it will be Sun, 6 Feb 2028. (The site is hosted by the Oxford e-Research Centre with data provided by the Department of Physics, University of Oxford) -
Peter42 at 21:18 PM on 30 May 2012It hasn't warmed since 1998
The last paragraph of the post from Hutch44uk (#178) below, together with the extensive comment on this thread about evidence and statistical significance, prompts two questions, which hopefully will be discussed by supporters of both sides of the AGW issue. "hutch44uk at 22:02 PM on 30 April, 2012 Not that a sign of increasing temperature proves that humans are causing it, but just dealing with the argument.. The article starts with a straw man logical fallacy 'No, it hasn't been cooling since 1998.' implying that was Carter's position. No warming doesn't imply cooling. According to the latest HadCRUT4 data, there is no statistically significant increase in temperature (0.083C/dec +/-0.172C/dec). It is also stressed in the HadCRUT4 report that it cannot be said yet whether 2005 or 2010 are the hottest on record." Q1. A number of comments emphasise the relevance of a sufficient period of observations, in order to determine trends or stasis. Assuming the HadCRUT4 data referenced above is indeed correct, and assuming the quoted temperature increase and range of error remained constant, after what time would that data become statistically significant? The next question is wider, given the depth of technical discussion on this thread, but I think very relevant to the AGW issue. While most people rely on formal bodies for direction on scientific opinion (in the case of climate change, on the IPCC and national authorities), it is obvious that many contributors to this thread have the technical knowledge to form their own views independently (while obviously drawing on scientific and other published literature). Q2. If you have presently reached the conclusion that there is, or is not, significant anthropological global warming (AGW) occurring at present, whose primary mechanism is through the greenhouse gas effect (GHG), what credible data and information over what period would you require (rather than simply some authoritative opinion), for you to change your mind? I look forward very much to informed comment on these questions, as such will assist me in my own analysis. Thank you. -
funglestrumpet at 20:28 PM on 30 May 20122012 SkS Weekly Digest #21
Seeing as comments seem to have ceased on this posting, perhaps I can just put forward a suggestion for the steering group managing this site to consider. Why not extend the scientific discussion to include the releative pros and cons of remedial actions to combat climate change, such as wind or solar or nuclear or tidal or whatever comes along. That is a vast topic for discussion and would attract a whole new body of scientific opinion. If that area of debate could be as well steered as it currently is on pure climate science, there is no reason why it shouldn't be the 'go to' site for the latest science on such matters as geo-engineering, renewables of all shades, nuclear of all forms, etc. etc. Imagine having a scientific question on, say, solar engergy and knowing the sks would be the first port of call for the answer, if the question has been answered yet, of course, and if not, then what the latest thinking is. Perhaps it might need a whole new site, but I personally would like to see this site take on the challenge as I think it has a highly deserved reputation for excellence and see no reason why that should not be applied more widely. Perhaps an exploratory email to those scientists prominent in discussions on the technologies related to tackling climate change to find out how they would feel about supporting the venture, not only by way of contributory articles, but also moderating the comments from Joe Public, such as myself, might help. Or, you could slowly include articles on the topic of remedial action and let it build from there. Perhaps inviting Professor David Mackay to contribute, citing his TED talk on renewables as the reason for the invite, might be a starter. Of course, you could run a special week of such articles to sow the seeds of the expansion in subject matter for the site, assuming it interests you, of course. You could include advisory issues, such as what difference 'fracking' produced natural gas will make to the problem if developed to the full. This would give the public has a focal point for information before they make political decisions on whether to support it or not. Finally, letting it be known that this site is moving on to the next stage of the issue, the implication being that the science is sufficiently well settled for such a move to be logical, would take a lot of wind out of a lot of sails. -
Dikran Marsupial at 18:58 PM on 30 May 2012Models are unreliable
Clyde asks: "Would you want heart surgery done by a doctor who has performed say 100 successful operations or by a doctor who has used a computer to project/predict how to do the operation?" This is an obviously bogus analogy. Heart surgery is performed routinely these days, so it is easy to find heart surgeons who have performed 100 successful operations. However climatology as a field is only a couple hundred years old and it takes at least 30 years worth of observations to get a clear picture of what the climate is doing, thus there is no climatologist that has made 100 successful (independent) predictions of future climate. Sadly observations of future climate are not available at the current time, so projections based on computer simulations are the best tool we have at the moment for exploring the consequences of a given course of action (or inaction). If Clyde has a better solution, then lets hear it. BTW, if computer simulations were of no value, then one would ask why computer simulation is widely used in training surgeons? -
Composer99 at 15:33 PM on 30 May 2012Models are unreliable
Clyde, you appear to be attempting to make a case against climate science (or at least, echoing Dr Pielke Sr's case) on the basis of its use of computer models to project future states of the climate. This is likely to be an exercise in futility on your part. As I intimated on the Bob Carter thread, the mainstream scientific position on climate is the result of an intertwining web of: (1) Physics & chemistry theory (ranging from quantum-mechanic radiative properties of IR-trapping gases, to the physics of blackbodies, to the chemistry of ocean buffering of CO2, to many other strands of theory besides); (2) Lab or computer experiment (starting with Tyndall's experiments demonstrating the atmospheric IR-trapping gases and confirming the atmospheric IR-trapping 'greenhouse' effect all the way to the elaborate atmosphere-ocean-surface coupled models of the present); (3) Empirical observation (the surface, satellite & sea surface temperature datasets, measured ocean heat content, measured crysophere melt, shifting wind currents & atmospheric cells, shifting animal & plant distribution, and so on). It it this intertwining of these various strands of evidence which has led to the formation of the generally-accepted scientific consensus on climate change, as expressed by the IPCC, the US NAS, the UK Royal Society, and virtually every major national, transnational, or intranational scientific organization. Even supposing you could chip away at the reliability & accuracy of computer models, you would still have an enormous task ahead of you to knock down enough of the theory, experiment & observation supporting the mainstream consensus to cause a substantial re-think. -
scaddenp at 14:44 PM on 30 May 2012Models are unreliable
Just on the RC discussion you might like to look at this comment and surrounding context. -
Bob Loblaw at 14:41 PM on 30 May 2012Models are unreliable
Last comment for now... Clyde: if you want to see why the name of Pielke Sr. gets the reaction it does here, read the discussions available here, where he has participated in some comment threads, and there have been numerous blog posts commenting on his arguments. Note that Pielke Sr. does not seem to allow comments at his own blog, so it isn't easy to engage in a discussion with him about them. I've already done some searching for you (the search box is in the upper left corner of the SkS page). You can try reading these blog posts and discussions: Pielke Sr and scientific equivocation: don't beat around the bush, Roger Response to Roger Pielke Sr. One-Sided 'Skepticism' Chasing Pielke's Goodyear Blimp SkS Responses to Pielke Sr. Questions Pielke Sr. Agrees with SkS on Reducing Carbon Emissions Pielke Sr. and SkS Disagreements and Open Questions Pielke Sr. and SkS Warming Estimates Pielke Sr. and SkS Dialogue Final Summary Pielke Sr. Misinforms High School StudentsModerator Response: (Rob P) Removed dead link -
Bob Loblaw at 14:22 PM on 30 May 2012Models are unreliable
Clyde: you said "I know enough to understand a failed prediction. Do you want me to post the links to the failed predictions/projections? Please do so, but keep in mind that here at SkS you will be expected to back your position up with references to real scientific literature (not just blog posts). Before you start to post your own stuff, though, you may want to review the series of posts found using the Lessons from Predictions search item. There is a button that will do this search for you near the top left of the SkS page (just above "Most Used Climate Myths"). -
Bob Loblaw at 14:13 PM on 30 May 2012Models are unreliable
Clyde: What is your definition of a "computer modeler"? On what basis do you claim that any particular "climatology expert" is not knowledgeable about computer modeling, and how would this affect the work that they are doing? I think that you are creating a strawman "computer modeling expert", in a futile attempt to pretend that climatologists can't do "computer modeling". Many climate modelers have physics and mathematics in their background, and at least one I know personally works in a mathematics department. I would consider myself to be a "climatologist", and I have written "climate models" (microclimate) from scratch. My background is physical geography, but - I have studied numerical methods, including finite difference solutions to partial differential equations. - I have coded numerical solutions to radiative transfer, atmospheric turbulent heat transfer, and soil thermal diffusion problems. - I know from study and experience the issues related to floating-point arithmetic, and how to avoid them. - I have coded the required root-finding procedures for complex, non-linear systems. - I wrote my first computer program before I took my first computer course, and before most people had a clue what "Computer Science" was (or would be). I never took a second computer course, but I have written serious code in three different languages, simple code in a few more, and can read read quite a few more than that. And I know that "Computer Science" students often don't get exposed to half the stuff that I have learned that is necessary to do "climate modeling" correctly. - my first numerical programming was done on punch cards, fed into a mainframe computer. I've been doing programing for almost 35 years. What else would I need in my background to convince you that I know enough about "computer modeling"? I seemed to convince my PhD thesis examining board that the modeling work I did was valid - and that board included an engineer that asked me why I used a secant root finding method instead of Newton-Raphson, and a physicist that said that when he read my thesis he discovered a field of study that he could have been very happy doing instead of physics. I agree that the science is above your head. It doesn't have to stay that way if you are willing to learn. Start by giving me your definition of "computer modeler", and what makes you think that people doing climatology aren't capable of it... -
scaddenp at 14:04 PM on 30 May 2012Models are unreliable
Clyde, what on earth makes you think modelling teams dont include heavy-duty modelling folk? As to "failed predictions" that pick up off blogs, there are a couple of things to check. First, check the source of the prediction. The usual denialist stuff is make claims about a prediction that are not actually made and since its a straw man, (take note of error bars) then its easy to demolish. All models are wrong, but some predictions are far more robust than others. A converse page of robust model predictions together with papers that do the prediction and papers that confirm it can be found here Second, modellers usually judge models by skill. Ie the ability of models to make better predictions than some simpler method (ie that nothing is changing). Climate models have no skill for instance at decadal-level predictions. This is common "skeptic" ploy. As to Piekle, perhaps you should follow the discussion with the modellers at Realclimate? In short, you cannot make naive comparisons of models and observations. If you still think there is clear case of model "being wrong" supported by papers, then by all means post links. -
muoncounter at 13:26 PM on 30 May 2012Models are unreliable
"heart surgery done ... by a doctor who has used a computer to project/predict how to do the operation?" What nonsense. Medicine uses computer imaging, based on models of how the body interacts with magnetic fields, sound and/or radiation. Oil exploration uses computer modeling based on seismic techniques. Is there a car or airplane that can function without a computer? Why is climate science held to the false standard that 'computer models don't work'? "You can input all the physics & chemistry you want into a computer. Doesn't mean what comes out is accurate." No, but it does mean that we can eliminate things that can't be verified by models. We can eliminate the idea that climate change is purely natural. -
michael sweet at 13:05 PM on 30 May 2012Renewables can't provide baseload power
curiousd, You would need a new grid to transmit the energy efficiently. It is hard to imagine that they would follow a rational design in the USA instead of choosing a series of short term fixes. I have heard that DC might be more efficient but would have greater political issues. If people want it to work bad enough they can make it work. For what the Iraq war cost you could build a new grid and build enough solar to power the whole country. (and still have money left over). People have to decide it is worth the effort. -
Clyde at 13:00 PM on 30 May 2012Models are unreliable
Jim Eager 506# I've never seen any credit given to computer modelers. Would you want heart surgery done by a doctor who has performed say 100 successful operations or by a doctor who has used a computer to project/predict how to do the operation? Would you bet your life on the future global warming projections/predictions coming from computers? I read a few other blogs. As i said earlier the science is above my head. I know enough to understand a failed prediction. Do you want me to post the links to the failed predictions/projections? From my brief time of reading this blog Rodger Pielke Sr is not one of the favorites around here. Why doesn't somebody ( you if your qualified) refute his claims on climate model predictions/projections? I'm not saying Rodger is right or wrong. He has an open challenge to prove him wrong & nobody has taken him up on it. He admits when he is wrong. He had to eat crow after a discussion he had with dana1981. You can input all the physics & chemistry you want into a computer. Doesn't mean what comes out is accurate. Have a nice day -
Jim Eager at 10:11 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
And 3) My totally uninformed opinion is just as valid and worthy of equal consideration as your highly informed and hard-won expertise, if not more so. -
Bob Lacatena at 09:51 AM on 30 May 2012Dead Ahead: Less Rainfall for Drought-Sensitive Southern Hemisphere Regions?
34, Steve, But choosing 1900 is a convenient cherry pick, because it obscures the effects of AGW, which are known to have really taken hold in the 1970s, with other climate events. In fact, if you look at the data you can very clearly see that rainfall increased in the first half of the century. 32, Tom, Your points are valid, except that: 1) If they computed proper trends then the impact of an early event like that is not going to impact the curve as strongly. You can also, if you prefer, go from 1950 forward:
2) You can not necessarily say that all warming is equivalent. In particular, the changes in rainfall patterns have a lot to do with the expansion of the Hadley Cells and the movement of the ITCZ. Admittedly, greater evaporation has something to do with it, but even that doesn't say anything about where the rain will fall.
We had a discussion similar to this one about the Texas drought, and Australia is the flip side of the coin. Here is a diagram of the expansion and poleward movement of the Hadley cell in the Southern Hemisphere. This may well be responsible, now or in time, for adding more seasonal rainfall to the north and drying out the rest of the continent.
From Observed poleward expansion of the Hadley circulation since 1979 – Hu & Fu (2007):
The ITCZ from various sources:
-
Tom Curtis at 09:35 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
vroomie @35:"I'm a geologist, dagnabit, *not* a computer expert"
You are forgetting the first axiom of denier's (and unfortunately that of too many elements of the media) that: 1) If you are expert in any subject, you are an expert in every subject in which you agree with my opinion. The second axiom is: 2) If you are an expert in a particular subject, if I disagree with you on that particular subject your stated opinions are based on fraud and conspiracy. -
vrooomie at 09:10 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Clyde@7, you ask: "Why is it that folks who critique AGW are dismissed if their not experts in climate science, but we should just accept a climate scientist's work on models when their not experts in computer modeling?" The reasons are vasried, well-documented, and are scientifically rigorous, as to why so-called "fake" experts are robustly, and rightly, questioned. To paraphrase another user here at SkS, you cannot believe just one scientist; you CAN, however, believe thousands. And at this time, many thousands who are bona fide experts in all the subjects relevant to AGW share a consensus, a consensus which is *vehemently* opposed by those who don't have the chops to refute that consensus. DB@19: Thank you fro correcting my bad "Netiquette." I'm still learning all this modern-fangled computer, HTTP stuff. I'm a geologist, dagnabit, *not* a computer expert...>;-D -
adavid at 08:45 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Jim and Tom good catch. It would have been better for me to have written "the influence of the sun on global temperatures peaked 10,000 years ago". -
Tom Curtis at 07:49 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
adavid @30, solar radiation has been close to constant, with variations of well less than 1% over the last 10,000 years. What peaked about 12 thousand years ago was Northern Hemisphere summer insolation. Because this peak was due to the orientation of the Earth to the Sun, it made little difference to the Earth's total insolation. -
Jim Eager at 07:28 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Adavid, that would be orbitally driven northern high latitude summer insolation that peaked 10,000 years ago. What's more relevant for the current warming is that since ~1980 there has been no correlation between change in insolation and rising global mean temperature. -
Jim Eager at 07:15 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
In other words, Clyde has no evidence what so ever, only conjecture and assumption. A question for you, Clyde: Which would you find more believable as a climate modeler, a climate scientist, or rather team of scientists, who are also competent at building a computer model of the physics and chemistry of the coupled land-ocean-atmosphere system, or an expert at computer modeling who knows absolutely nothing about the underlying physics and chemistry of the coupled land-ocean-atmosphere system that is being modeled? (Why should they, they are not climate scientists, they're computer modelers, while practically all physical scientists work intensively with computers.) And why did you fail to consider that climate scientists work with actual computer modelers when developing climate models, as I suggested, before leaping to defend your assertion that climate scientists have no expertise in the use of computers? Also posted here in case Clyde want's to continue to defend his misconceptions. -
Jim Eager at 07:15 AM on 30 May 2012Models are unreliable
Continued from here In other words, Clyde has no evidence what so ever, only conjecture and assumption. A question for you, Clyde: Which would you find more believable as a climate modeler, a climate scientist, or rather team of scientists, who are also competent at building a computer model of the physics and chemistry of the coupled land-ocean-atmosphere system, or an expert at computer modeling who knows absolutely nothing about the underlying physics and chemistry of the coupled land-ocean-atmosphere system that is being modeled? (Why should they, they are not climate scientists, they're computer modelers, while practically all physical scientists work intensively with computers.) And why did you fail to consider that climate scientists work with actual computer modelers when developing climate models, as I suggested, before leaping to defend your assertion that climate scientists have no expertise in the use of computers? -
adavid at 06:48 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Bob Carter first referred to himself as a Palaeoclimatologist in his book "Climate: The Counter-Consensus". Apart from a brief mention of peering at ocean sediment cores, there was no reference to any of his geological work in that book. The glaring oversight to me is mentioning the sun with respect to recent warming. Any palaeoclimatologist knows that incoming solar radiation peaked 10,000 years ago. -
john byatt at 06:46 AM on 30 May 2012IEA CO2 Emissions Update 2011 - the Good News and the Bad
Apologies for using URL, too much time at RC -
john byatt at 06:17 AM on 30 May 2012IEA CO2 Emissions Update 2011 - the Good News and the Bad
Tom Wigley, Uni Adelaide Switching from coal to methane would slightly increase global warming until 2050 or longer http://www.sciencedaily.com/releases/2011/09/110908124505.htmModerator Response: TC: Link connected. -
bath_ed at 06:04 AM on 30 May 2012Dead Ahead: Less Rainfall for Drought-Sensitive Southern Hemisphere Regions?
Back to the topic at hand - the many unique plants of the winter-rainfall zones of South Africa and Australia and the effect on them of a possible southerly retreat of the rain-bearing westerlies - it will be of no comfort to them if rainfall increases in other climatic zones. The endemic plants of the Cape aren't going to derive any benefit if the Lowveld or Kalahari etc get wetter and neither will the plants of south-west Australia suddenly move to the tropical savannas and semi-deserts of the north. I think this illustrates the problems of glib, sweeping contrarian statements such as 'a warmer world is a wetter world' which may be true in a very general sense but are used to distract from the specific problems different regions, ecosystems and species face. A small point: the rainfall maps of Australia and South Africa have a significant difference in that the Australia one separates out the arid zones and the South Africa one doesn't - only the far southwest of the winter rainfall zone is relatively well-watered; the north especially (such as the RSA/Namibia border) is fully arid, just what little rain it gets falls mainly in the winter half of the year. Therefore rain-fed crops and many plant species are restricted to only the southwest. -
Andy Skuce at 05:55 AM on 30 May 2012IEA CO2 Emissions Update 2011 - the Good News and the Bad
BWTrainer: The IEA estimates are explicitly for CO2 emissions from fossil-fuel combustion. The non-combusted fugitive methane emissions from natural gas production would not therefore be included. The conclusions of Howarth et al have been disputed by other Cornell researchers, in which they claim that the Howarth study: assumed a very high estimate for methane leakage; compared heat rather than electrical energy generation, (favouring coal); and used a short time period that did not sufficiently take into account the long term effects of CO2 compared to methane emissions. -
IanC at 05:45 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Clyde, Climate modelling involves writing down a set of equations to describe the underlying physics of the climate system, and then solve the resulting set of equations to give you a numerical answer. Computers are nothing more than a tool for number crunching. In short, a climate modeller will have to be an expert, by default, in whatever programming language they work in, just as a image designer must be proficient with photoshop, a writer must be proficient with the language. One only needs to know how to get the computer to compute 1+1, not necessarily how the computer arrives at the answer. -
dana1981 at 05:25 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Clyde - all future predictions about everything are based on models. If I drop a coin off a bridge and calculate how long it will take to reach the ground, I'm using a model. That model, like climate models, is based on fundamental physical laws. Also, all models are "wrong," including the one in my simple example. No model is perfect, but models can be useful tools - climate models certainly are (i.e. see here). As for your modelers question, I still don't understand what you're asking. My point was that scientists don't necessarily have to be modeling experts to use a climate model (depending on what they're using it for). Regardless you seem to think models play a much bigger role in climate science than they actually do (i.e. see Rob H's comment #27). -
dana1981 at 05:10 AM on 30 May 2012IEA CO2 Emissions Update 2011 - the Good News and the Bad
BWTrainer - the IPCC scenarios consider non-CO2 GHGs separately, so we would have to compare observed methane emissions to the emissions in their scenarios to see where we're at. -
Rob Honeycutt at 04:35 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Clyde @ 25... No, all future predictions/projections are not just based on models. It's based in physics. The radiative properties of the atmosphere is the basis for projections. It's as simple as, if you turn up the heat, it gets hotter. The models are only attempting to inform us about the various kinds of responses we can expect, not whether there is going to be a response or not. The models help scientists reduce the uncertainties related to the sensitivity of the climate in response to warming. The models help identify the various fingerprints of AGW. -
Clyde at 04:20 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
dana1981 17# If i want me house rewired i call an electrician. I can turn lights on & off too. I wouldn't try to rewire my house tho. Anybody can turn a computer on, doesn't make them a computer expert. Have a nice day all -
Clyde at 04:17 AM on 30 May 2012Bob Carter's Financial Post Gish Gallop of Scientific Denial
Jim Eager 15# Only evidence i have is their bio's & Wiki pages. I can't say I've read every climate scientists bio & Wiki page. The ones i have read make no reference to having any expertise in the use of computers. I respectfully disagree with the models playing a small role. All future predictions/projections are based on models. If the models are wrong wouldn't the predictions/projections be wrong too?Moderator Response: [DB] Please relocate discussions of models to the Models are unreliable thread, where they are more properly on-topic. -
Dikran Marsupial at 04:11 AM on 30 May 2012CO2 has a short residence time
Hi Martin, I'm sorry I haven't replied to your email yet (exam time here, only just finished my marking). I'm about to go home now, so I'll try and answer a few quick points now and will be back tomorrow. 1a. yes, the atmospheric reservoir is just the mass of carbon in the atmosphere. 1b. (Fi - Fe) is calculated via the mass balance argument (conservation of mass implies that it is the same as dC - anthropogenic emissions). So if you download the mauna loa dataset and the emissions (fossile fuels and land use change, you should be able to reproduce figure 6, which I used to calibrate the model). 2. The data for dC and anthro emissions are known with good certainty, so while Fi and Fe are uncertain, the difference between them is constrained by the uncertainty on dC and anthro emissions. I doubt the error from this source has a greater effect on the results than the crudeness of the model, which is only the simplest possible approximation. As I said in the paper it isn't of any use for quantative predictions, only for getting a qualitative understanding of the very basics. 3. or rounding somewhere. 4. I think that residence time would be for pre-industrial conditions, rather that todays, as we have increased the atmospheric reservoir above its equilibrium value (and the uptake will have increased a bit as well). The residence time (for a given isotope) is the same regardless of its origin. The important point is to explain why there is very little "anthropogenic" CO2 in the excess above the equilibrium concentration, which is because it gets replced by "natural" CO2. The residence time is really the time an individual molecule stays in the atmosphere on average, so it is really only properly defined in terms of a subset of one molecule. Sorry, have to dash now, my lift home has arrived! Hope this helps. -
Bob Lacatena at 04:06 AM on 30 May 2012CO2 limits will harm the economy
94, D.B., I think my problem with that particular argument is that the developed world isn't bending over backwards right now to improve quality of life around the world, and the carbon footprint involved is in no way the "limiting factor." That argument amounts to "there are poor people, and if we were to actually decide to try to help them, this would make it even harder, so we shouldn't do anything." The reality is, however, that western perceptions of what will be helpful (and in fact are feasible) are simply not relevant. The simplistic idea that you'll simply change every society to live like "The West" is absurd. Real solutions involve things like this.
Prev 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 Next
