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dvaytw at 02:24 AM on 15 October 2013Temp record is unreliable
I'm doing another AGW debate and was wondering if someone can give me a quick response to the following claim, or refer me to where I can read up on it myself:
"To start with the "global warming" claim. It is based on a graph showing that "mean annual global temperature" has been increasing.This claim fails from two fundamental facts
1. No average temperature of any part of the earth's surface, over any period, has ever been made. How can you derive a "global average" when you do not even have a single "local" average?
What they actually use is the procedure used from 1850, which is to make one measurement a day at the weather station from a maximum/minimum thermometer. The mean of these two is taken to be the average. No statistician could agree that a plausible average can be obtained this way. The potential bias is more than the claimed "global warming.
2. The sample is grossly unrepresentative of the earth's surface, mostly near to towns. No statistician could accept an "average" based on such a poor sample.
It cannot possibly be "corrected" It is of interest that frantic efforts to "correct" for these uncorrectable errors have produced mean temperature records for the USA and China which show no overall "warming" at all. If they were able to "correct" the rest, the same result is likely."
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Claude Allaigre at 02:18 AM on 15 October 2013Two degrees: how we imagine climate change
It might be interesting to mention Hansen and Sato's "Paleoclimate Implications for Human-Made Climate Change" where it is written :
We conclude that the ocean core data are correct in indicating that global temperature was only slightly higher in the Eemian and Holsteinian interglacial periods than in the Holocene, at most by about 1°C, but probably by only several tenths of a degree Celsius. (p 18)
Augmentation of peak Holocene temperature by even 1°C would be sufficient to trigger powerful amplifying polar feedbacks, leading to a planet at least as warm as in the Eemian and Holsteinian periods, making ice sheet disintegration and large sea level rise inevitable. (p 19)BAU scenarios result in global warming of the order of 3-6°C. It is this scenario for which we assert that multi-meter sea level rise on the century time scale are not only possible, but almost dead certain. Such a huge rapidly increasing climate forcing dwarfs anything in the paleoclimate record. Antarctic ice shelves would disappear and the lower reaches of the Antarctic ice sheets would experience summer melt comparable to that on Greenland today. (p 20)
We have presented evidence in this paper that prior interglacial periods were less than 1°C warmer than the Holocene maximum. If we are correct in that conclusion, the EU2C scenario implies a sea level rise of many meters. It is difficult to predict a time scale for the sea level rise, but it would be dangerous and foolish to take such a global warming scenario as a goal. (p 20)Conceivably a 2°C target is based partly on a perception of what is politically realistic, rather than a statement of pure science. In any event, our science analysis suggests that such a target is not only unwise, but likely a disaster scenario. (p 27)
I don't know about his science but do you agree that the 2°C limit is indeed a politically realistic target rather than a statement of pure science ?
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DSL at 02:10 AM on 15 October 2013Why climate change contrarians owe us a (scientific) explanation
History Reader, to give you an illustration of my first claim, take a pinball machine. Build a device that shoots the pinball into the machine at precisely the same speed each time. Shoot the ball in and then track the ball. Now, shift every bumper one millimeter to the left (a tiny shift!), and each kicker a millimeter to the right. Now shoot the ball again. Same track? Same score (without using the flippers)? No. Or, if the same score, not for the same reasons.
Undoubtedly there will be some natural variation that will affect the track on each run beyond the re-placement of the bumpers and kickers, but the re-placement of those elements certainly has an effect, and over a long number of runs, the difference between the two states (pre-re-placement and re-placement) will become clear, as the signals of short-term natural variation (climate read: ENSO, PDO, 11-year solar cycle) start to average out.
Of course, we're not shifting the climate a millimeter to the left. Given the geological bounds of climate (the bounds set by precedence and physics), we're moving the bumpers and kickers about an inch to the left. However, we're not doing it all at once. It feels immediate to the evolutionary progress of the biosphere, but to the individual human it feels quite slow and relatively harmless. The ball is still bouncing around at the top of the machine, though.
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Stephen Leahy at 02:04 AM on 15 October 2013Ocean In Critical State from Cumulative Impacts
TonyW 2C is political and what countries have agreed to stay below under the UNFCCC. And are supposed to sign a legally-binding treaty in 2015 on their cuts to get there. It's a target to aim for. 1.5C is a better target, and some countries are fighting for that.
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DSL at 01:58 AM on 15 October 2013Why climate change contrarians owe us a (scientific) explanation
History read, the scientific explanation for attribution of weather events to global warming is pretty simple, really. All specific weather events have occurred as they have actually occurred as a result of global warming. To imagine a global warming-free world where Sandy develops and tracks as it actually did last year is irrational, to say the least. An increase in global energy storage affects every part of the system, and from a variety of directions.
Also, with something like hurricanes, most non-experts I've talked with baseline their experience in the 1970s or 1980s, as if that were the period before global warming. It was not, and global warming = persistent change. The science on hurricane development under global warming is, at best, only loosely aligned under one theory. Journalists, in general, have done badly in communicating this area of the science to the general public.
As far as humans being powerful is concerned, note that humans are simply enhancing an already very powerful natural mechanism--the greenhouse effect. The theory of the greenhouse effect is extremely well-supported by direct observation/measurement, and it hasn't faced a serious challenge in about a century. We are simply doubling the strength of one major component of that effect, and through that doubling we enhance the power of several other components of that effect (H2O and CH4).
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Tom Curtis at 00:59 AM on 15 October 2013Why climate change contrarians owe us a (scientific) explanation
History reader @6, you refer to "... the media hyped global cooling scare ...". As a reader of history, you should know better than to get your information from people who are known to falsify the record. When deniers have to make fake Time magazine covers in order to prove the existence of a "media hyped global cooling scare", that tells you that the actual evidence does not support their claim.
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MA Rodger at 00:48 AM on 15 October 2013Why climate change contrarians owe us a (scientific) explanation
History Reader @66.
While all your questions may not be so readily answered as the first example you set, that first is hardily an obscure question. And neither is its answer. Your question of course should be framed a little differently as obviously Sandy was not a product of human endeaviour. Rather its path and intensity was much influenced by human endeaviour.
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PluviAL at 00:38 AM on 15 October 2013SkS social experiment: using comment ratings to help moderation
What happened to the reply option?
This is my favorite subject, on which I would like to write a book discussing the propositions offered by Quillian on OFD (Open Forum control Democracy.) The key ingredient his concept adds is to quantify the voting according to the pre-qualifications of the commentator. A commentator who has a lot of approval on the subject would weigh in much more heavily than a novice, a troll, or a bot, as defined by the user community in prior commentary. It parrellels peer review by design, but in a dynamic process. I call the concept ASCEND as one chapter in my new book Pluvinergy. Although the book is about climate adjustment technology, the ability to discuss global adjustments reasonably is critical, thus the necessity of the topic.
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vrooomie at 00:15 AM on 15 October 2013Why climate change contrarians owe us a (scientific) explanation
"AGW however is a direct threat to those who adhere to the ideology of free market and libertarianism, since AGW very clearly indicates what is required to avoid the consequences."
Even more importantly, Iin my opinion, is the fact that AGW itself is one of the largest and most stark examples of a market failure, and to those who fervently believe in lassiez faire capitalism as the Holy Grail that can solve all our ills, it is a *very* inconvenient fact that lays bare the falsity of that long-held supposition.
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History reader at 00:11 AM on 15 October 2013Why climate change contrarians owe us a (scientific) explanation
Whenever we hear things like "worst flood in 100 years", "strongest hurricane since..." "most tornadoes in 50 years" or whatever here are the things that come to my mind.
Identify and explain all of the natural factors that caused that record event in the past long before man had much effect on CO2 then identify and explain all of the man made factors that made the recent event equal or exceed the past natural events.
That is the scientific explaination I am looking for.
If man caused Sandy then what caused the more powerful storm that hit New York in 1821?
If nature caused 5 hurricanes to hit the east coast in 1954-55 then why do people claim that the recent fewer and less powerful east coast storms are caused by man?
Prior to the strong La Nina (cooler Pacific waters) fueled Joplin tornado outbreak there was the super outbreak of tornadoes in 1974 (another strong La Nina) fueled outbreak. Why was the 1974 outbreak that occurred during the media hyped global cooling scare different than the Joplin outbreak where people blamed warming. Even though both were actually caused by the same thing that fuels all severe weather. Interaction between air masses of different temperatures.
Why was nature as powerful in the past as man is claimed to be today?
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Eric (skeptic) at 21:57 PM on 14 October 2013Levitus et al. Find Global Warming Continues to Heat the Oceans
Thanks scaddenp. I quickly scanned it and will address their conclusion of relatively low uncertainty (20% or less). But the deeper ocean has more uncertainty which includes model uncertainty from the assimilation method that I mentioned above. That will be my main focus.
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Lanfear at 20:40 PM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
"The reason is: the religious institutions around the world do accept AGW"
I have to disagree with you on your analysis.
The reason is that your objection does not touch the core of the comparison (which you seem to acknowledge), which is that people who denies the scientific premise of AGW do that based on their belief/ideology because AGW is a direct threat to their belief system.
I do want to take a moment and clarify my stance: I consider both (politcal) ideology and religions equal in that the other promotes some economic of social idea on a pedestal, while the latter places a superbeing on it. To the degree where this becomes sacrosanct and no critique is tolerated/accepted.
In this situation, a scientific theory which directly threatens the dogma of the believer causes the believer to be in a state of cognitive dissonance and the solution is either to modify the dogma to accommodate the new information, abandon it altogether, or reject the science, not based on facts, but on secondary reasons (ad hominem etc.).
AGW is not directly contradicting the central tenets of most of the religions (although some seem to interpret the texts differently). Hence your reference to Vatican acceptance is not very strong. It would be better to observe how vehemently the various religions has opposed, and changed their dogma (eg. the Anglican Church of England), due to research in evolution and cosmology, both which directly contradicts what the sacred texts claim to be the truth.
AGW however is a direct threat to those who adhere to the ideology of free market and libertarianism, since AGW very clearly indicates what is required to avoid the consequences.
The crowd that follows and repeats the lies as "alternative theories" on WUWT or such blogs, are poeple who for some reasons are unable or too lazy to verify the "skeptic claims".
Are you sure there is not even a single person among that group of people, who does not really believe in what is published on those blogs? The last sentence is in essence saying: They accept the "alternative theories" on blind faith, contrary to what science says. Is this really so different to how some of the (traditionally) religious people are rejecting science on the field of evolution and cosmology?
Obligatory disclaimer: I am not a expert on neither theology, nor AGW/Evolution/Cosmology. Any corrections are much appreciated.
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JasonB at 19:57 PM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
Jubble @ 63,
The scientific argument has clearly been won - there was never an argument in the first place.
That's not true. Arrhenius' 1896 paper was thought to have been refuted for half a century due to a flawed experiment by J. Koch in 1900. (Interesting read.) It took a long time for the scientific community to come around.
The irony, of course, is that "skeptics" now raise all the same objections that were raised and dealt with years ago by real scientists in forming the modern consensus view, all the while proclaiming that they are the ones fighting the closed-minded establishment that has "already made up its mind" oblivious to the fact that the "skeptics" actually represent the holdovers of the old estalishment view that took so long to overcome with scientific evidence!
It's like Flat Earthers complaining that modern scientists are stuck in their ways and not considering new, alternative theories!
This is also an interesting read that you might like.
I have just posted the following on WUWT - let's see what sort of response I get:
You may be surprised by what they think is convincing evidence. :-)
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Jubble at 19:26 PM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
MARoger @56 & JasonB @62: The scientific argument has clearly been won - there was never an argument in the first place.
The popular argument is very much up for grabs, though. Throughout history, proving the science has only ever been the first important step of many before concerted action can be taken. Examples are smog in London in the mid 20th century (4000 deaths in 4 days 1952 were initially blamed on influenza - it wasn't until 1956 that legislation was brought in) and of course tobacco.
Climate contrarians (as they like to be known) will not produce the science, because it is not there. They will instead try to denigrate the scientists, badging climate science as not a real science at all (other than those cherry-picked studies that can be woven into a superficially convincing argument for "natural variability"), and describing the IPCC as a corrupt group of inept close-knit non-scientists, rather than a panel summarising the work of 1000's of scientists.
I have just posted the following on WUWT - let's see what sort of response I get:
"I am looking to be convinced that AGW is a myth or not a problem. I admit that currently I believe that on balance it isn’t a myth and is a problem. My background is in science, with a joint hons undergraduate degree in Math and Physics from the University of Nottingham, England and a post-graduate in applied statistics (operational research) from the London School of Economics.
Fire away – how can I be convinced? I’ve read “Climate – the Counter Consensus”, if that helps."
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JasonB at 16:31 PM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
Jubble @ 54:
The main counter-AGW argument appears to be: The climate has changed before and no-one truly understands it, therefore there may be some other explanation of the current changes than anthropogenic that is not accounted for in the climate science and the models.
That's an argument from ignorance, though. They may not truly understand it, but to say that no-one does asserts a level of knowledge on their part that they clearly lack.
I think it's worth reiterating that AGW was not invented to explain "the current changes". The current changes were predicted long before they were observed — Svente Arrhenius' first computed a climate sensitivity of 4C in 1896!
I would point those people to:
1. Spencer Weart's "The Discovery of Global Warming", showing just how long the theory has been around and how it has evolved over time.
2. Frank Capra's short film "The Unchained Goddess" from the 1950s talking about the possible consequences of mankind's CO2 emissions.
3. Richard Alley's talk at AGU in 2009, "The Biggest Control Knob — Carbon Dioxide in Earth's Climate History", giving an excellent overview of the role CO2 has played in Earth's history.
The fact that climate has changed before — and we know why — is one of the reasons we can predict what will happen this time!
Thinking that, in spite of all this, the science might still be wrong and the problem may not be as bad as it currently seems, is wishful thinking for which there is no evidence and a bad risk management strategy. I think it's safe to say, as the OP essentially does, that a prima facie case has been made and the burden of proof has now shifted on to the other side if they wish to argue for inaction.
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JasonB at 14:41 PM on 14 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
SASM @ 133,
I think we all understand that this type of comparison isn’t meaningful in the initial stages of the forecast. But, as time advances forward the min/max trend lines become wider, and once they are as wide as the noisy temperature data, then the location of the origin really shouldn’t matter. For example, in your chart @126, you can see that the min/max trend lines are outside the 2.5%/97.5% model bands by 2013 or 2014.
Nevertheless, in both my chart and yours, it is clear that global temperatures are at the very low end of the model projections. You show the +/-2.5% bands and the current HADCRUT4 data is touching the lower 2.5% band. I read that as there was only a 2.5% chance that the global temperature would reach this level.
This is circular reasoning/begging the question. You're claiming that as time moves forward the min/max trend lines behave more and more like temperature bands, then use the observation that the temperature data is touching the lower 2.5% band to argue there is a problem.
Tom's graph @ 126 very clearly showed the actual trend line that should be compared to the min/max trend lines. The actual trend line is about half way between the mean trend and the minimum trend. It is well within the range. QED.
If you disagree, then how would any of you determine that the models are inaccurate? What is your method of testing and validation?
Look at the second figure in the OP — Tamino's graph of projection trends and observation trends, together with their uncertainties.
If they were disjoint — i.e. if the projected trends with their ranges did not overlap meaningfully with the observed trends plus their uncertainties, then we'd want to go back and figure out what we missed (or whether, instead, we had miscalculated something).
We're a long way from that.
BTW, as has already been pointed out, HADCRUT4 has a known systematic error because it omits the fastest-warming regions of the globe. The models have no such error in their temperature calculations. If you're getting close to showing there could be a problem (which you aren't, but at some point it's possible) then it's worth checking to see whether it's what you're using for observations that are the cause, rather than the models. (This has happened before, with UAH, for example.) Alternatively, you could apply HADCRUT4's algorithm to the model output to compare like-with-like.
If your position is robust then it should stand up when using multiple data sets, not just the one data set that is known to underestimate warming. In other words, when you're right on the margin, you don't want to be accussed of cherry-picking the data set to prove your point.
In this case, however, we're not right on the margin, but it's good to be prepared should we eventually be so.
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JasonB at 14:08 PM on 14 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
Leto @ 145,
A professional poker player sits down with a novice. The hands and flow of money are totally unpredictable in the short term, but we know who is going to win by the end of the evening
In fact, the entire casino industry is based on the fact that over a large number of games with a large number of people, a small bias in favour of the house will give them a profit even if they can't predict whether they will win or lose any particular game.
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Climate Bob at 13:37 PM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
Fossil fuel companies are not stupid and neither are they poor. They spend millions each year on research, scientists and technicians, Climate change is threatening their business and if it was a false science or if there was another way out they could easily spend the money on research and find it and prove it. Denying that is is happening is only wasting time and a lot of people are going to die.
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barry1487 at 12:52 PM on 14 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
"You cannot have accurate long term forecasts and inaccurate short term forecasts."
I just flipped 7 heads and 3 tails. The model that predicts very nearly 50%/50% distribution over 1000 coin flips, then, cannot be right.
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scaddenp at 11:48 AM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
One other point for Elephant.
"10 percent of children in the UK for example live in poverty. We also cannot provide our current energy needs."
What is considered poverty is a rather relative measure. As is what you define as an energy "need"? You could also argue that poverty is actually a distribution problem and that having abundant energy isnt going to remove poverty. MacKay estimates UK consumption at 125kWh/p/d while USA manager 250kWh/p/d. By comparison Hong Kong manages on 80kWh/p/d and India on less than 20. I'd say there was scope to redefine "need" somewhat.
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scaddenp at 10:52 AM on 14 October 2013Levitus et al. Find Global Warming Continues to Heat the Oceans
Probably worth also have a scan of Von Schuckmann and La Traon 2011, "How well can we derive Global Ocean Indicators from Argo data?"
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John Cook at 08:10 AM on 14 October 2013SkS social experiment: using comment ratings to help moderation
Jim Pettit, I'm well aware of the danger of denier gamification of the rating system (I read extensively on the topic before installing this system). Gamification is slightly more difficult at SkS because in order to rate, one needs to register a user account with a working email address. It's not impossible to register multiple accounts, by any means, but raising the bar does weed out a significant number of potential trolls. Because each rating is tracked, even if someone does gamify the system with multiple accounts, if they are detected, their ratings can be instantly removed. So there is very little return on investment for deniers wishing to undermine our rating system.
But here's another interesting twist. There has been scholarly research into using social network analysis to detect sock puppets (multiple accounts by a single user) engaging in exactly this type of behaviour. If deniers do try sockpuppeting at SkS, they present a wonderful research opportunity. So bring it on :-)
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Doug Bostrom at 06:50 AM on 14 October 2013Ocean In Critical State from Cumulative Impacts
Some interesting back and forth on this issue and lessons for the value of staying within one's boundary of expertise or at least being duly cautious can be followed here:
Seattle Times series on local threats imposed by ocean acidification
Respected local meteorology researcher Dr. Cliff Mass weighs in
Author of Seattle Times piece Craig Welch responds to Dr. Mass
An authoritative NOAA/Washington State report on the whole affair, "Scientific Summary of Ocean Acidification in Washington State Marine Waters" (pdf, 176 pages)
Thanks for this article, John. We really do need to be more careful with the ocean and what's in it.
(I should add that the NOAA/Washington item has includes truly excellent background information on the pH problem)
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scaddenp at 06:44 AM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
Elephant.
"I am entitled to that opinion and that is what I say."
You are entitled to your own values and political opinions, but you cannot have your own version of reality. What you are saying is that your opinion is not based on any reasonable evidence so there is no basis for anyone else to be interested in what you think.
"It is easy for everyone on here to talk about 'scientific evidence' when your view is the evidence of an army of climate scientists. Given that there is a distinct absence of investigation into the merits or not of climate science it will always be a one sided debate."
As far as I can see all this statement means is that you dont believe the evidence therefore you must conclude that somehow the evidence is flawed, rather than question the basis by which you came to your own opinion instead. You are agreeing there is no evidence to support your view but you hold to that believe anyway?
In fact, the army of scientists is constant investigating the merits of the science - one positive that came out of the climategate leaks is the robust nature of climate debate between climate scientists. If there is one group of people that have scientists, funding, resources and particularly the motivation to attack climate science, then it is the fossil fuel industry. Instead of doing the science they instead spend their money on disinformation. Why is that? Well because their own scientists tell them the science is solid so it would be a waste of money. This is my industry. I dont know of a single climate denier among colleague in my department.
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scaddenp at 06:30 AM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
" The climate has changed before and no-one truly understands it,"
Except of course that the current climate theory has no problem explaining past change. The problems with past climate change is that, depending on how far back you go, there are multiple possible explanation, all consistent with modern climate theory that can account for the observation. The problem is that is not easy to extract both accurate records for past climate and accurate forcings. However, as the IPCC chapter on paleoclimate shows, theory accounts very adequately for observation given those constraints. "nobody truly understands it" is simply willful ignorance and wishful thinking.
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grindupBaker at 05:54 AM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
Elephant #36. You waxed philosophical and weren't moderated. Here goes. As I move rapidly to my Final Rewards I'd like to think our bunch can strain enough against its natural powerful purpose, to provide sacks of flesh to aimlessly carry its genes around and do their bidding slavishly, to advance even to proper space ships (which we ain't gonna do by burning rotted vegetables). You have one foot assisting the 3-month time horizon of the fossil-fuel Corporate kings and the other foot planted firmly in the future when our sun blinks out, but you missed the potential fun stuff for future humans in-between. I'm for the fun thing of new ideas, innovation and whatnot, rather than the miserable philosophy you have of <paraphrasing> species come, species go, so what, that I first heard on a David Suzuki CBC phone-in 15 years ago. I wonder who is with me and who is with you.
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deweaver at 03:48 AM on 14 October 2013Ocean In Critical State from Cumulative Impacts
The article is a bit hysterical and becomes misleading as biases are intermingled with facts and hypothesis.
For example: "Ensure effective implementation of community- and ecosystem-based management, favoring small-scale fisheries." implies that small-scale fisheries can't be/ aren't as destructive as "large scale" fisheries. This is a bias not supported by facts. The US gulf coast shrimp trawlers (small boats) clear cut almost the entire gulf every year and put ten times more phosphorous back into the water column than is contributed by the Mississippi River and all the upstream runoff and sewerage from the central part of the US. This impacts eutrophication and the hypoxic zone formation.
Concepts like: "Build a global infrastructure for high seas governance that is fit-for-purpose" have to face the observational reality described in Public Choice theory that the behavior of that "global infrastructure" will be in the organizations self-interest. The problem is not "building the infrastructure", but designing such infrastructure in such a way that its organizational and individual self-interest aligns with the interest of the planet and humanity. In setting up such a structure, existing fishing interests will be well represented and they will create governance structures to prevent competition from unrepresented future "innovation" in offshore open ocean aquaculture that would put them out of business.
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Levitus et al. Find Global Warming Continues to Heat the Oceans
Eric (skeptic) - Again, I would refer you to the actual literature, Levitus et al 2012, and the appendix on error calculation.
They describe in considerable detail their use of irregularly sampled temperature measurements and resampling down to 1 degree fields - and in their analysis they discuss the standard deviation of temperatures over distance:
"...showing supplemental Figures S12 and S13 which are maps of the number of temperature observations and standard deviation of all temperature observations used in this study at 700m depth (from Locarnini et al. [2010]). Figures S14 and S15 show the same statistics for 1750m depth. Examination of maps of the standard deviation demonstrate that this statistic is relatively homogenous and isotropic on the data averaging scales we use in our objective analyses for most of the world ocean." (emphasis added)
Your concern would be valid only if there was sufficient short range variation in temperature anomaly, sufficient non-uniformity, to make the measurements unusable - and as Levitus et al have noted, that is not the case. Temperature anomaly data is sufficiently homogenous for irregular and relatively sparse sampling to track, and the uncertainties involved are part and parcel of their error bars.
Keep in mind that, like in atmospheric temperature anomalies (Hansen & Lebedeff 1987, while temperatures may vary over short spatial scales oceanic temperature anomalies have a far stronger correlation over distance. Lacking evidence contradicting the Levitus error calculations (and while you have expressed concerns, you have not presented either data or references supporting such), I would consider their data valid.
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Eric (skeptic) at 01:08 AM on 14 October 2013Levitus et al. Find Global Warming Continues to Heat the Oceans
KR and Dave123, thanks for the replies. I had read a website a few months ago that explained the way Levitus et all assimilated the ARGO data into their climate model. Basically the model would predict temperatures, they would compare those to the real temperature measurements, then adjust the model for a better fit in an iterative process. The key point is that the model provided the energy change results not the measurements directly. When I find that website again, I will read through it and post what I find here.
I read through the appendix of Levitus et al 2012 and saw a process for estimating the error of a data smoothing algorithm. I'm not sure how I can evaluate that yet.
The crux of the issue is determining how much heat has percolated into the deeper ocean. KR, do you mean that the "mass effect" allows the integration of many estimates of heat transfer to determine an aggregate heat transfer over large regions? That's true as long as the factors and effects are somewhat uniform. I'm not sure that is true in cases where both heat transfer and heat accumulation vary over relatively small regions. Nonuniformity seems to be the case looking at figures S5 (which is averaged longitudinally) and S6 (which is not).
And Dave123, a linear regression through data points will only work if there is a somewhat linear rise (or fall) in temperature. That's true for some basins to some extent and true for the world, but is only true sometimes for individual floats. A higher variance in any particular float means a higher standard deviation and uncertainty.
But as I said above, I owe you a better answer once I find the web site (it was not a paper, but a NOAA website describing the assimilation process).
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MA Rodger at 00:47 AM on 14 October 2013Why climate change contrarians owe us a (scientific) explanation
Jubble @54.
If there is some theory that stands up to scrutiny which would relegate AGW to a non-threatening phenomenon as the contrarians insist, it is a simple question to ask - What is this theory? Do pray tell. I would not be alone in giving any serious suggestion the time of day. And the 3% climatologists who publish papers that do not fit the consensus - they are not very prolific so identifying such a theory shouldn't be too much of an ask as there is little enough literature in which such a theory can be hiding.But I don't hold my breath. The whole reason d'etre of this post is that such a theory does not exist. To the great unwashed, the contrarian "side" may appear the same as the scientific "side" but that similarity is an illusion promoted by contrarians and denialists. Scientifically, the difference is that the contrarians continually deny the veracity of whole swathes of science for no other reason than such science is inconvenient for their theorising.
If the IPCC establish a 95% certainty that human influence has been the dominant cause of rising temperatures over the last 60 years, that does not mean the likes of Elephant In The Room can assume the remaining 5% is his to do with as he will, like some five quid note found lying on the pavement.
If positive human forcings have been overestimated a bit and/or the negative ones & natural ones & the temperature rise underestimated a bit and the climate wobbles proved to be on the larger side, that presents a situation that would take up the lion's share of the 5%. So all there is lying on the pavement for contrarians to pick up is a bent penny piece. The remaining uncetrtainty gives no scope to deny AGW. -
Ger at 22:43 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
Good article: Can you add Einstein to list of scientist as he showed that the geometry you choose is determing what physics you can measure? And for the Dutch: J.C. Lely, as designer and implementor of one of the biggest waterworks. Both had to wait and sit for 20 years before they were heard. Both had a lot of trouble getting their ideas across. Both needed a 'crisis' to get through the fog of 'common sense' beliefs from vested interest.
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Andrew Mclaren at 22:41 PM on 13 October 20132013 SkS Weekly News Roundup #41B
As per the lead for the first article, methane offgassing from formerly frozen permafrost layers is a huge concern, but I was given to understand that it is mainly due to bacterial decomposition of organic material following the melt, rather than being spontaneously released from suspension (as with subsea methane clathrates).
Maybe I am nitpicking but the phrase "[Permafrost melt] also releases vast amounts of heat-trapping greenhouse gases" might be better qualified as 'indirectly releases'. Although the quantities involved are definitely massive.
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Jubble at 21:42 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
MA Roger @49: You may be right and it would be powerful to be able to say that there is no peer-reviewed scientific evidence that refutes AGW that hasn't since been found to be incorrect. The point I was trying to make was that to a non-specialist both sides of the debate can look the same, as described by Elephant in the Room @50.
Elephant in the Room @50: I'd be very interested in continuing the discussion with you as you make exactly the point I made in @43 - that both sides of the debate appear the same, meaning you need to make up your own mind what to believe.
The main counter-AGW argument appears to be: The climate has changed before and no-one truly understands it, therefore there may be some other explanation of the current changes than anthropogenic that is not accounted for in the climate science and the models.
The IPCC would actually agree with that I think and put the chance that some other explanation is the dominant cause at 5%.
Do you think there is a chance that they are right?
For sake of argument, lets say that humanity is the dominant cause of climate change since 1950, but we don't yet know that it is for certain at the moment. There would be a lot of scientists trying to find out, wouldn't there? And most of the scientific results they came up with would support the currently unknown scientific truth, wouldn't it?
The alternative hypothesis is that humanity is not the dominant cause, and we don't know that for certain at the moment. In that situation, you would expect a lot of the science to support the view that humanity is not the dominant cause. That not being the case, you would need to account for the 97% pro-AGW; 3% anti-AGW balance - the counter-consensus argument: there is a large scale confirmation bias among climate scientists, who are looking for evidence for their pre-conceived notions. You would need to conclude that climate scientists are all bad at their job, or are corrupt in some way. That seems incredible to me - if it were the case, surely there would be a few good climate scientists out there finding the evidence that refuted AGW? More than a few?
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gpwayne at 21:18 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
This is my response to the post by Elephant In The Room (#36).
"As for scientific explanation - you seem to be laying down the gauntlet for people to refute with scientific evidence something that is currently theory".
To be clear, I am insisting that the only way to challenge science is with better science. Opinions need to be validated, else they remain mere opinion – and as we’ll see, opinions do not – indeed cannot – add to our scientific knowledge. Only science itself does that.
The threat of man-made climate change is a theory that currently the IPCC have a 95 percent certainty in (previously 90 percent). It's all semantics.
No, it’s all statistics. The fact you confuse the two is revealing. (It reveals an agenda, to forestall the obvious question).
100 percent, 90, 50. It is immaterial. We could all quote our 'out of 10' view on any given subject. It DOES NOT add weight to the argument.
Nor does TYPING IN CAPITALS.
Probability is hardly immaterial. Again, your comment reveals an agenda, a lack of understanding, or a refusal to do so. In short, inferential or observational science (where results cannot be tested against a ‘control’ Earth, for example) often relies on a statistical determination. Confidence levels are crucial to understanding the uncertainties, evaluating them, and how they are resolved.
However, it is my belief, and it is a belief, that the effect of the Co2 that we as humans churn out is minimal compared to the amount produced through natural variation.
Well, that’s true in a broad sense, (although it isn't natural variation that causes the effect - natural variation is a description of how the effect changes over time. Your misapplication of the term is also part of the sub-text of my article).
Anyway, the pre-industrial greenhouse effect warms us by around 30 degrees C. Human contributions have added 0.8 degrees C. But since the system is non-linear, and highly reactive, it is a small increase that concerns us because its effect may have consequences far in excess of its proportion.
To ask a person or persons to refute 'evidence' with 'science' is ludicrous in the same way that it would have been to ask people to challenge that the world was once deemed to be flat.
This is a serious failure of logic, if you don’t mind me saying so. How else can one challenge scientific evidence, except with better scientific evidence? And your analogy is inappropriate. The belief that the world was flat – not widely held at any time since Ptolemy, by the way – was not a scientific view, but after the birth of Christ, largely a religious one. The appropriate analogy would be to suggest it would be ‘ludicrous’ to challenge the round Earth evidence by citing a religious belief that it wasn’t – exactly the point I made in the article.
And I can assure you that our brief incursion here will have no effect on the long term future.
And I can assure you that you have no way at all of knowing that. Your assurances are not remotely credible, since like the rest of us, you cannot predict the future. Attempts to do so smack of superstition, however.
Are we complaining that we are returning [carbon] to the air after it had once been sequested?
No, we are concerned about the speed at which we’re doing it, and the warming it's causing.
Are we complaining about sea levels when we know full well that this is a natural event that occurs post Ice Epoch?
No, we are concerned that the sea level will rise so fast we will not be able to adapt, and that massive amounts of damage will be done to fragile systems, including the human economy. (By the way, describing these issues as 'complaints' is tone-trolling. They are not complaints, and your attempts to dismiss them as such are more products of an agenda).
Is it the planets fault that we as humans choose to build houses in coastal areas that will as history tells us become inundated again with water?
Is it the Bangladeshi’s fault they live in Bangladesh? The Dutch in Holland? That mankind has settled along river deltas like the Indus, Ganges etc because the plains were fertile, and the rivers promoted transport, trade and exchange of ideas?
Take a good look; there is enough history there to tell you what has been and what will be again.
In other words, we’ll repeat history because we can’t learn from it. How fatalistic (and also a non-sequitur).
Do you really wish to throw all your eggs in one basket for the sake of a global threat that isn't really a threat at all? [my emphasis]
This closing remark serves to make the key point I raised in my article. You claim climate change ‘isn’t really a threat at all’.
To which I say this: since you can't possibly know this - it's another claim to be able to read the future - in fact that’s just your opinion. To convince me, you’ll have to demonstrate a high probability for the claim – and you can’t. For that, you need science, and you don't have any.
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Dave123 at 20:48 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
Yes, you do need to supply the details. And you need to get to know the site. Your argument has already been dealt with here:
http://www.skepticalscience.com/co2-higher-in-past.htm
Not referring to this indicates you're not really interested in much of anything but stopping discussion with 'gotcha's that work in your local pub.
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Elephant In The Room at 19:41 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
Comments Policy
No ad hominem attacks. Personally attacking other users gets us no closer to understanding the science. For example, comments containing the words 'religion' and 'conspiracy' tend to get moderated. Comments using labels like 'alarmist' and 'denier' as derogatory terms are usually skating on thin ice.
Note: denier, contrarian and alarmist all used in the post by gpwayne . Or do the rules only apply to people that question the science? Just asking a valid question here?
Moderator Response:[PW] Moderation complaints/whining noted; move on to the topic of the thread. If you have solid scientific backup for your previously-unsupported assertionss, provide them. Otherwise, further detractive commentary *will* be moderated.
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Dave123 at 19:40 PM on 13 October 2013Levitus et al. Find Global Warming Continues to Heat the Oceans
Eric- So what you've said is that after I pointed out some gaps, you went back and tried to fix it. That's good. If you truly aspire to be a compelling sceptic, you need to do this first, not as an afterthought. And I'd suggest you should assume that the people writing those papers have done so. Peer reviewers tend to be a little reactive when they see a paper than hasn't properly acknowledged prior work in a field. It's one of the easiest things to 'ding' a paper for.
Let me add one other point about accuracy that you seem to have missed and KR didn't discuss. We are interested in the change of temperature in the deep oceans. Thus the standard procedure of computing the temperature anamoly for each device and working range applies. A given Argo Float measures a hypothetical temperature of 8.023 C at a depth of 1500 meters. The measurement is repeated on a regular basis of 5 years. You can run a regression line through the temperatures, which does much the same thing as taking the average of all the temperatures and substracting that average from each data point. Now you have the anamolies, and those are independent of whether the "true" temperature was 8.021 or 8.025. If a given thermocouple reads a little high, it always reads a little high. For a narrow (or not so narrow) range of temperatures you can treat that error as a constant offset. Looking at the anomoly also allows us to pool data across multiple floats and thus create a statistic that represents the total ocean heat content change.
Add this to the law of large numbers and you get a statistically sound measurement of an increase in heat going into the lower depths.
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Elephant In The Room at 19:22 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
@dave 123 (#37)
Responsibility for details. I don't need to duplicate countless graphs on here to demonstrate our previous relationship with Co2. Now, if you want to tell me that the average global temperature isn't 22 degrees or that the current level of Co2 isn't the lowest it has been for 1 of 3 periods over the last 650 million years then I suppose I should go and find a graph for it. Do you really want me to do that?
This thread is asking 'contrarians' to provide scientific evidence that something doesn't exist when there isn't irrefutible evidence that it does. There is more credibility in referring to (if that's not sufficient) our previous temperature record.
We as humans are destroying this planet and everything else that lives on it. We cannot feed ourselves as it is. 10 percent of children in the UK for example live in poverty. We also cannot provide our current energy needs. Carbon dioxide emmissions follow from that because we currently need to and have to burn fossil fuels. There is no escaping it. I would rather Co2 wasn't coughed up into the atmosphere but that isn't going to happen. Furthermore I don't believe the net effect is as great as is being suggested. I am entitled to that opinion and that is what I say.
It is easy for everyone on here to talk about 'scientific evidence' when your view is the evidence of an army of climate scientists. Given that there is a distinct absence of investigation into the merits or not of climate science it will always be a one sided debate. If by association that makes you right and me wrong then it is very sad state of affairs indeed as let's be honest the view of the IPCC has just upped its belief to 95 percent from 90 percent. While there is still that uncertainty people shall continue to question the a science.
I am posting on a website that clearly supports the view that man made climate change is occurring. In the same way, if I had argued for man made climate change on a site that refutes man made climate change I would expect the same reaction. And here lies the problem. This is why there will never been any agreement.
Can the moderators just clarify the posting rules. Is it a rule that you must provide a graph every time you want to question a given subject? It seems that I am receiving quite a bit of back lash for sharing my opinion on a subject matter?
Also, would calling someone a tone troll also be an example of an ad hominen remark?
Not a very friendly welcome I have to say. I wasn't rude to anyone was I? Or does offering alternative views automatically make you a troll. (-snip-)
Moderator Response:[DB] "Is it a rule that you must provide a graph every time you want to question a given subject? It seems that I am receiving quite a bit of back lash for sharing my opinion on a subject matter?"
This venue is based in the scienctific method and discusses the science of climate change, from the standpoint of what the primary literature has to say about it. Every article here at SkS references the primary literature via hyperlinked text. Discussion in the comment threads is based on increasing the level of understanding of that science, hence the participation of subject matter experts and other talented individuals.
You will find that opinions are welcome here, but opinions that differ from the primary literature not themselves based on peer-reviewed articles themselves appearing in the primary literature are essentially caterwauling. And will then be treated as such. Repetitious behavior in this regard contravenes the "No Sloganeering" portion of the Comments Policy; which, based on your subsequent comment you have indeed read.
Future comments by you will be held to adherence to that policy with increasing rigor.
"would calling someone a tone troll also be an example of an ad hominen remark"
That would depend upon the context used. If used verbatim as delineated by you, likely so. Please provide a link to the specific instance you denote. Generally, ad hominem refers to "to the man" instead of to the argumentation used by the person. To call someone's behavior and comments an example of tone trolling might be unhelpful in improving the dialogue, but is not ad hominem.
Tone trolling snipped.
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MA Rodger at 18:13 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
Jubble @43.
I would strongly disagree with your statement that "there isn't as much genuine science to refer to" within the theorising on a contrarian site. I would suggest that on such sites there is actually no genuine science to refer to whatsoever.
It is of course possible to point to scientific papers that appear to fit the bill. As an example of these, Wyatt's "Stadium Wave" hypothesis was referred to @18. But will this "Stadium Wave" hypothesis stand up to proper scrutiny? As I am a little familiar with the profiles of PDO & AMO before they have been converted into pretty harmonic waves, and also the post-2000 data, my answer is a definite "No it will not!"
Because absolutely none of the hypotheses or analyses paraded on contrarian sites stand up to proper scrutiny, with such an asymmetry, how can this be a debate with two sides? It is not. It is better characterised as 'one side' refusing to accept the evidence presented by the other but unable to provide a reasonable argument for such a refusal.It would be good if there were a "third way" to address this impass but tackling AGW is not a straightforward task. (If it were, we would just tackle it, like we did CFCs.) Tackling AGW is going to require changes that many will not immediately consider desirable. So if you don't see AGW is a problem, you will resist such change rather than support it. And a large section of the public, of the media, of our politicians are still unable to see AGW as a problem. (An example of such change and resistance, local to me, planting 175 sq km of sea with wind turbines 20 km off shore has turned the county into a hot-bed of NIMBYs. To them cutting carbon emissions by 750KtC, equal to half the county's total carbon footprint, that counts for nothing.)
This post argues that contrarians owe the world a genuine scientific explanation. To date they have presented no "genuine science" but instead make fools of the world by continually presenting forgeries.
If you cannot make good a debt you owe, you can be declared bankrupt. I think the time is long overdue that contrarians are declared bankrupt. And that is why I brand them deniers. -
Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
Stealth - "I’m just curious, what is your background?"
An Argument from Authority is a logical fallacy - it's the strength of the evidence and argument that matters, not the credentials of the person presenting a position. And regardless of your background, you have not supported your posts.
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Levitus et al. Find Global Warming Continues to Heat the Oceans
Eric (skeptic) - There are, quite frankly, a number of misconceptions present in your last post.
"The latter paper also notes that the accuracy of temperature measurement was 0.002C so measuring a 0.002C change is problematic." - Incorrect. You seem not to understand how the margin of error changes with multiple measurements, the law of large numbers. Measurement error decreases with the number of samples, with the rough proportion of 1/sqrt(n). The uncertainty of a single measurement is a vast overstatement of the uncertainty of multple measurements.
WRT to sampling grid size, regardless of whether or not the sample spacing is fine enough to resolve individual 'salt fingers', the mass effect of heat transfer is quite measureable. And that holds whether or not the phenomena driving the mass transfer of energy is below the scale requiring parameterization in a model - if it has a significant effect, that will show up in the larger scale measurements.
The core of your post, however, appears to be a claim that there are inaccuracies not accounted for in Levitus et al and the literature in general, inaccuracies sufficient to invalidate the presented data. I would strongly suggest you actually read Levitus et al 2012, in particular the appendix labeled "Error Estimates of Objectively Analyzed Oceanographic Data", and if you have any serious objections to their methods point them out. Otherwise, you are simply making vague and unsupported insinuations of inaccuracies without evidence - and such statements without evidence can in turn be dismissed without evidence.
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scaddenp at 12:34 PM on 13 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
"You cannot have accurate long term forecasts and inaccurate short term forecasts."
Um, I can forecast the average temperature for the month of May next year I suspect with greater accuracy than I can predict the average daily temperature for Sunday week times That is rather like the difference between weather and climate.
As to background - I program models for, among other things, thermal evolution of sedimentary basins and in particular the evolution of hydrocarbon geochemistry over time. This is to answer the questions like "does this basin produce hydrocarbons, and if so, when, how much and in what phases". More than most however, the problem is dominated by uncertainty and poor constraints.
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Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
Stealth does not appear to understand the difference between boundary and initial value problems.
Consider as an example Los Angeles freeway traffic. Predicting exact volume even a few hours from now (initial value problem) would require exact numbers of cars on the road, perhaps some estimates of how aggressively they are being driven, detailed road conditions, etc. From that you could make detailed and relatively exact projections of how traffic might behave a few hours later. But not for a week down the line - there's too much that can occur in the meantime.
If, however, you wish to make long term projections of what traffic might be (boundary value problem) - given information on population, predictions on neighborhood growth, planned on/off ramp construction, and perhaps the football schedule (for near-stadium effects), you can make an average traffic prediction years down the road. You won't be able to predict the exact number of cars passing a point on the road on a particular Tuesday five years ahead - but you can make excellent predictions of the averages. And in fact city planners do this all the time.
In terms of evaluating climate models, whose mean trends are a boundary value solution - the climate has many short term variations, and it is only to be expected that short term variations will indeed occur around energy bounded long term trends. Models are quite frankly doing very well right now:
In order for the models to be invalidated by observations, the long term trend would have to go beyond the boundaries - far enough that such a new trend +/- the range of variation departed from the model predictions +/- variations. That hasn't happened, not by a long shot - and (IMO) it won't, as we have a pretty good handle on the physics.
In the meantime, demanding impossible perfection from boundary condition models, in the presence of short term initial value variations, is just a logical fallacy.
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jmorpuss at 12:24 PM on 13 October 2013SkS social experiment: using comment ratings to help moderation
I think it would be a good idea to have a third option, maybe a grey thumb pointing sideways and would mean skeptical. And providing a dropdow of the voters names when you move your mouse over a icon may stop gaming and trolling
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Eric (skeptic) at 12:15 PM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
Dave123, thanks for the critique. The core of my alternative explanation follows after I comment on the ocean-has-missing-heat theory. Obviously my critique of Levitus deserves a more thorough explanation which is here
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Eric (skeptic) at 12:14 PM on 13 October 2013Levitus et al. Find Global Warming Continues to Heat the Oceans
In this thread I posted a link to Schmitt et al 2005 and stated that "The bottom line is we don't really know how much 'missing' atmospheric heat has wound up in the oceans." Dave123 replied that "the paper makes the case that mixing was faster than anticipated" and quoted form the paper here. He suggested checking cites so I did, although not all 71 of them. Searching within the cites for GCM was dry, but searching for ARGO brought up this paper: website: scientiamarina.revistas.csic.es path: /index.php/scientiamarina/article/viewFile/1384/1488 that suggests that the Schmitt results were localized that were not present in the rest of their Atlantic ocean cross section. I didn't pursue the cites further.
But more apropos is the Levitus papers themselves such as this one: World ocean heat content and thermosteric sea level change (0–2000 m), 1955–2010 In order to fill in missing data for the 700-2000m depth they have to model how much heat flows down from the 0-700 depth which has good coverage. The relatively small temperature changes that SASM asks about in post 28 is answered by Tom two posts later as being 0.1C over the period. However the annual energy change is roughly 1022 Joules so the temperature change for 6 x 1023 cubic cm of seawater with 4 J/g/C is 0.002C per year.
The answer to KR's reply a few posts later that the large number of sample points reduces the error: there are only 4 data points in each one degree grid square in the model in Levitus. The mixing shown in the Schmitt paper and the other paper linked above requires simulation at the 1 degree cell resolution to simulate the mixing processes.
The latter paper also notes that the accuracy of temperature measurement was 0.002C so measuring a 0.002C change is problematic. Also the ARGO network has about 3 degree spacing according to their website which makes it basically impossible to simulate the mixing, so it must be parameterized.
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john3 at 10:56 AM on 13 October 2013Ocean In Critical State from Cumulative Impacts
There is an additional threat to our oceans and that is the slowly increasing levels of mercury and other heavy metals. Heavy metals have been locked up (and away) for eons in coal reserves and when coal is burned, they aerosolise. Large amounts eventually settle in our oceans, are absorbed by biota such as algae and eventually make it up the food chain on to your dinner plate. Hence the limits on eating palargic fish such as sword fish no more than once a week. A recent three year study measuring tissue levels of heavy metals in 500 whales found alarmingly high levels. The study surmised that this was directly linked to a fall in whale fertility. and this would likely doom most whale populations within 100 years.
Yet another reason to leave coal in the ground. Thankfully many countries have excellent plans showing a switch to 100% renewables is entirely possible within 10 years. (See Beyondzeroemmissions).
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Bert from Eltham at 10:31 AM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
Jubble this 'third way' you speak of used to be peer reviewed science. That is evidence based knowledge from experts in their field to influence the policy makers such as our political institutions and business leaders. This has been paralysed by very dark forces that continually throw doubt on the peer reviewed scientific evidence. This is in a time where the peanut gallery is a worldwide phenomena due to the web. This peanut gallery is louder than the worlds experts. They do not have to win arguments with any logic or evidence. Just put up a constant noise to drown out the message that they disagree with.
I am sure that that these dark forces are somehow also exploiting a form of Poe's Law where the pseudo scientific sites on Global Warming are indistinguishable from the real scientific sites to the average layman. Bert
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Dave123 at 09:42 AM on 13 October 2013Why climate change contrarians owe us a (scientific) explanation
Eric, your citation of Schmitt (2005) puzzles me. First, the paper makes the case that mixing was faster than anticipated.
The significant vertical dispersion of tracer observed in this thermohaline staircase supports the idea that salt fingers significantly enhance mixing in certain parts of the main thermocline. Our derived salt diffusivity of 0.8j0.9 10j4 m2/s is an order of magnitude larger than that predicted for typical internal wave breaking within the mid-latitude thermocline. Indeed, for this low-latitude region, parameterization of mixing supported by the background internal wave field (32, 33) indicates that a diffusivity of only È0.02 10j4 m2/s should be expected. The tracer derived
diffusivity is also larger than that implied by microstructure measurements previously
made in this staircase (16, 25, 34). However, it is in agreement with the salt finger
model applied to those dissipation data (35), as well as to our new observations. Notably, the diapycnal tracer mixing rate observed in the western tropical Atlantic is 5 times that observed in the eastern subtropical Atlantic during NATRE, because of the presence of the thermohaline staircase. The staircase appears to transform the T-S structure of the thermocline waters entering the Caribbean, increasing the salinity and density of Antarctic Intermediate Water (36) and preconditioning it for sinking at higher latitudes. The efficient vertical transport within this strong tropical thermocline must be taken into account in oceanic and climate models, where the parameterization of diapycnal mixing continues to be a major uncertainty in assessing the ocean's ability tosequester heat, pollutants, and carbon dioxide.In otherwords, I don't think the paper can be read the way you're claiming. Beyond that, this paper is 8 years old. Did you do any work to check citations. If this were a class paper, I'd certainly demand evidence that you'd followed the scholarly trail and were presenting an opinion grounded on more than one paper. What work has been done since.
Then there's this question. There's instrumental data from the Argo floats. You've made no mention of this, only models. Why not? If you don't like the data, wouldn't your exposition be sounder if you brought this up and disposed of it?
If you want to create a synthesis, you need to do the work. Especially here, where the aggregate of people do follow the literature, check citations, and routinely attempt sound scholarly syntheses. Unless of course, you think picking a few papers is "good enough for a 'C'", in which case you'll not convince anyone here.
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Leto at 08:55 AM on 13 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
Stealth, you wrote:
I have noticed that no one has answered the question of their background. This leads me to speculate that you are unqualified to discuss software modeling and accuracy.
This and similar comments, along with your login name, appear to be attempts to pull rank by virtue of your software 'expertise'.
In fact, programming software is fairly easy for anyone with a basic sense of syntax and logic. The difficulty with software modelling is not really in the writing of the code, but in understanding the domain you are trying to model. You clearly have very little knowledge of the climate domain, and you seem resistant to the patient attempts of others to educate you.
You also wrote:
You cannot have accurate long term forecasts and inaccurate short term forecasts.
This patently false comment reveals that you do not understand - even in the broadest terms - what the models are trying to achieve and how they relate to the real world, perhaps because you are drawing faulty analogies with the one domain you do understand (aviation modelling). There are countless situations where long-term projections are possible despite short-term unpredictability.
For instance:
- A hose is running into a half-empty backyard swimming pool at a constant rate. People are splashing about in the pool, so the water level near a monitor fluctuates wildly, but the rise is linear in the long term. (This example from some other SkS poster.)
- Snow depth on a mountain increases in fits and starts during winter, and melts off in spring. The general rise and fall in snow depth over months is predictable, despite the poor predictability over days.
- A professional poker player sits down with a novice. The hands and flow of money are totally unpredictable in the short term, but we know who is going to win by the end of the evening.
Some systems are highly divergent, and small-short term effects propagate to create vastly different outcomes, like the proverbial butterfly flap. But others are highly convergent, and small short-term effects are swallowed up. This is particularly the case for climate modelling, when many of the short-term effects are merely moving heat around within the system, without substantially changing the cumulative and predictable heat imbalance due to GHGs.
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