So why do you choose to believe the methodologies of the most while not believing methodologies or a few? Solely based on numbers? That's pretty dangerous line of thinking in science and one that would still have us disregarding quite a few important scientific theories if that was the case.
Edit2:
Just to be clear, I am being skeptical here of both sides.
you raise a lot of good points, but concerning the methodology:
there is not a singular "complete" theory or set of hypotheses that could explain 20C warming without anthropgenic influence via CO". Most singular theories blame sun spots, variability or whatever process but forget to acknowledge all other lines of evidence from observations of TOA fluxes (top of the atmospherE), paelorecords and so on. The full "theory" of climate change has nothing to do with a majority vote, but with being the only theory so far that could not be disproved. All other attempts to explain 20C warming have holes in one way or another, if you are interested in a specific one, please dont hesitate to ask her e
On August 22 2013 04:58 Judicator wrote: Some thoughts, if you really think the peer review process is that stringent, then you have never submitted a paper, sat on a review committee, or in general tried to publish with your livelihood on the line. It's not as stringent as you think, and biased results gets by review committees all the time even at the prestigious journals like Nature/Science. I am not saying review committees are chaired by idiots, but I am saying that review committees are very much human. There's no guideline for model variables, and different people have different opinions on model construction, it's totally up to the researcher and their reasons for building their model.
The majority of scientists would claim that the peer review process is stringent.
I actually have first-hand experience of the stringency of the review process. I've submitted papers before including important stuff like one of the only derivations of Born's rule from a deterministic decoherence model. Usually they were rejected for reasons including the arbitrariness of a single assumption which I set out as a hypothesis, my omission of an equation that's valid in the continuous case (even though it follows from my treatment of the discretized case), or my temerity to leave some (admittedly important) questions unanswered and awaiting a future publication. Never has it been because of a technical or logical error. It's not easy to get a paper published in a good journal, even if you have something interesting to say and you're an honest scientist who double-checks and triple-checks his results.
In hindsight, though, I guess they were right to be so stringent. All my work that was refused could be (and is being) made much better if only more time is spent on it. Better for science to submit a really good paper and drive your home your point than leave a trail of second-rate papers that will confuse everyone. And that is a testament to the goodness of the peer review process.
Yes, reputation can play a role in bypassing the usual process and getting papers published that don't deserve to be in prestigious journals. But I don't feel this is a terrible thing in any of the hard sciences. You get bandwagons, but can the subject matter of an entire field of study be propelled by bandwagons? I don't think so. At the very least I'm going to ask for some proof before submitting to such a claim.
On August 22 2013 04:58 Judicator wrote:As for mutually reinforcing evidence, what's going on here has happened before in the history of science, just because the academic masses agree with something, does not make it the truth. Since when did reading what the other side has to say become such a no-no? Just because a denialist links something, doesn't mean you shouldn't at least read it and give some consideration. I mean if you care enough to argue/debate the topic on an internet forum, what precludes you from considering both sides of the debate?
It happens. It's just something you always have to prove rather than assume. Remember that this little detour stems from a comment by Darkwhite that climate scientists are doing nothing more than tweaking free variables to retrospectively fit the data. A pretty bold claim, and I'd like it to be supported by some evidence.
P.S -- I don't even understand why he had to couch it in those terms when we have a professional climate scientist here who might have been able to set him aright on this point if only he'd asked the question.
On August 21 2013 06:57 dabbeljuh wrote: Dear Darkwhite, so while I agree with many of your points, I cannot agree with two points:
a) "the only way to test the accuracy of your models is to wait for the years to tick by" That is untrue. You can check the IPCC chapter on model evaluation of AR4 or AR5 or the hundreds of papers released each year on model evaluation. The line of argument is multifold - the models should be based on physical principles (i.e., Navier Stokes is essentially Newton) - the models should be verifiable in parts that have not been tuned( i.e., you tune the mean temperature, if yourmodel gives you the yearly seasonality automatically, you would argue that it has some inherent merits) - the models should react to external forcings on the short term in a plausible way (i.e., volcanoes. The dissipationfluctuation theorem in physics sais that a model reacts usually in the mode of its biggest variability. So, if we can say that our models react "correctly" in their spatial and temporal fingerprint towards a perturbation as in a volcanoe, we can infer that it is plausible that it reacts similiar to other perturbations" - connections between seasonality and climate change: the change throughout a year is massive and fast. if the models capture it, it is highly plausible that they capture a much smaller and slower change through increase in co2
These statements seem a bit weird at first glance - how does a model's ability to predict seasonal changes in any way validates it's ability to predict changes caused by changes in the composition of the atmosphere? They are caused by entirely different thingies. I don't see how being able to predict one parameter's short term influence on the system correctly means you can predict some other parameters influence correctly - or am I misreading the argument at the moment? I haven't bothered to read the AR explanations (a tad lazy), but I'm assuming the arguments for their validity are somewhat more complex - I'd dare to guess that these statements in their simplified forma are factually incorrect.
I also get a bit irritated at the first argument when it comes up - it's somewhat disconcerting that it is deemed necessary to state that climate models are based on physics (what else would they be based on - pirate activity?)
So, if you're done shooting at the messenger, could we have a discussion over which part of the data and scientific studies which establish the validity of the two propositions I mentioned you disagree with?
Yup. Pretty much all that needs to be shown on every page. This graph is as real as it gets, raw data measured from 39,000 temperature stations worldwide, no computer models, no predictions, nothing, it is exactly what it shows.
Also keep in mind that when you look at this graph you can see the temperature is not just increasing, it is accelerating. Hypothetically, if the rate became exponential and the temperature doubled each year, and it took 50 years to increase by 1.5C, it won't take another 50 years to increase to +3C, it will take only 1 year.
I don't think you can look at this graph and think that it is going to plummet back to norm any time soon. Of course any science newbie can easily see a trend.
What annoys me most is that subsequent posters seemingly ignore posts even directly above them... -_-
So, if you're done shooting at the messenger, could we have a discussion over which part of the data and scientific studies which establish the validity of the two propositions I mentioned you disagree with?
Yup. Pretty much all that needs to be shown on every page. This graph is as real as it gets, raw data measured from 39,000 temperature stations worldwide, no computer models, no predictions, nothing, it is exactly what it shows.
Also keep in mind that when you look at this graph you can see the temperature is not just increasing, it is accelerating. Hypothetically, if the rate became exponential and the temperature doubled each year, and it took 50 years to increase by 1.5C, it won't take another 50 years to increase to +3C, it will take only 1 year.
I don't think you can look at this graph and think that it is going to plummet back to norm any time soon. Of course any science newbie can easily see a trend.
What annoys me most is that subsequent posters seemingly ignore posts even directly above them... -_-
I do not mean to be an ass but did we rally have 39K stations back in the day? Could urbanization effect the stations temperature readings?Say a station in the 1950's was in the middle of nowhere and now is in the middle of a city.
These statements seem a bit weird at first glance - how does a model's ability to predict seasonal changes in any way validates it's ability to predict changes caused by changes in the composition of the atmosphere? They are caused by entirely different thingies. I don't see how being able to predict one parameter's short term influence on the system correctly means you can predict some other parameters influence correctly - or am I misreading the argument at the moment? I haven't bothered to read the AR explanations (a tad lazy), but I'm assuming the arguments for their validity are somewhat more complex - I'd dare to guess that these statements in their simplified forma are factually incorrect.
I also get a bit irritated at the first argument when it comes up - it's somewhat disconcerting that it is deemed necessary to state that climate models are based on physics (what else would they be based on - pirate activity?)
okay, I was perhaps to fast when typing these reasons out.
While you are right that seasonal changes are caused by different forcing than global warming, it is still - in a simplified way- a change in radiative forcing, one time due to geometry, one time due to greenhouse gases. And if your full system behaves realistically towards a forcing change that you can measure (seasons), you can be quit epositive that it will not goe bollocks when confronted with a different chang ein radiation (the actual radiative effect of greenhouse gases is very simple to calculate and not under debate. The question is if the followup feedback mechanisms react correctly).
and, @ the physics argument: this is mostly against critics that believe that what they see in projections are statistical models that are just tuned to data (as in economics or most sciences where you do not have underlying primary equations). While climate models can be quite wrong in many aspects, the core of what they simulate is physically reasonable, this was all I wanted to make in that point.
I hope this clarifies it a little (and again, I am typing things here quite rapidly, I dont think they are factually wrong, but sometimes maybe a little unprecise)
I do not mean to be an ass but did we rally have 39K stations back in the day? Could urbanization effect the stations temperature readings?Say a station in the 1950's was in the middle of nowhere and now is in the middle of a city.
you are true that the number of stations changed in time, if you have any software installed that can visualize netCDFs you can for example visualize the station date of hadCRUt http://www.metoffice.gov.uk/hadobs/hadcrut4/data/current/download.html and you will see how the number of stations increases in time.
the effect of urbanization is included in the reconstruction processes, there are filters for that kind of behaviour (i.e., if it is known that there was no city and than there is a city, this station will be recalibrated). As all of the measurements only measure _anomalies_ and not full temperatures, this is easy to do and it has been shown by separate independent research groups (the latest was a group of non climate scientists from Berkeley) that the effect is small, see results from the berkeley group http://berkeleyearth.org/summary-of-findings
Also keep in mind that when you look at this graph you can see the temperature is not just increasing, it is accelerating. Hypothetically, if the rate became exponential and the temperature doubled each year, and it took 50 years to increase by 1.5C, it won't take another 50 years to increase to +3C, it will take only 1 year.
I don't think you can look at this graph and think that it is going to plummet back to norm any time soon. Of course any science newbie can easily see a trend.
What annoys me most is that subsequent posters seemingly ignore posts even directly above them... -_-
I have to jump in here, as I believe this kind of plots can be misleading.
While we have an exponentiel increase in greenhouse gases, the logarithmic nature of saturation leads to a more or less linear effect in forcing. Therefore we expect in the long run a linear response of warming towards human influence. If for periods of time "reality" warms faster, and than slower again, that has to due with indidivuel events (volcanoes, aerosol forcing changes, internal variability) and not so much with an massively increased external human forcing.
So, to make it short: I dont see an exponential warming in the next decades (As long as nothing bad happens with the tundra and methan =)
And I was wondering if/when Earth will ever get this way? What are the current projected models of the worst it will get as far as temperature and ocean levels etc. Moreover, what data do you guys use based on the current knowledge of Venus and it's runaway greenhouse effect in order to help your own research for Earth?
IIRC, for those who don't watch the docu, Venus basically erupted the entire planet because of lack of plate techtonics. The planet is believed to have had oceans, but with the lack of magnetic shield because of the slow rotation of the planet the solar winds slowly evaporated the ocean into the atmosphere, but the solar winds slowly ripped away the molecules away from the planet so now it's basically fucked.
Venus's case is completely different, as you can imagine. Before thinking about evaporating oceans, we are worrying about melting ice. And raising ocean levels (probably the most dangerous problem caused by global warming, desertification can't compare with being forced to move all the coastal population of China and India).
On August 20 2013 05:08 TricksAre4Figs wrote: Now, having said that, we know that 99% of people are scientifically illiterate and cannot interpret data themselves. We must rely on those professionals who study the field to give their best interpretations. If there is never a debate on the issue and only one side is allowed to speak then I'm afraid I can't believe they are telling the whole truth. A dissenting opinion must be allowed to make it's case in order for the truth to come out.
Imagine if astronomers discovered an asteroid heading toward Earth. They checked their calculations, double-checked them, triple-checked them. Every time they found that Earth is in the path of trajectory of the asteroid.
In that circumstance would you jump up and make a big song and dance about "dissenting opinion"? If you did, would you be surprised if you tested the patience of most astronomers?
The problem is that climate science neither has nor deserves the same level of trust as physics. Climate science is largely in the business of making poorly based claims about the far future while consistently having their models contradicted by the short term developments. Climate science should be lumped with economics and psychology, other fields which similarly apply naive models to much too complicated systems and pretend they have the scientific rigor of a natural science.
As Gringo pointed out, most climate scientists are actually trained physicists. If their field really was so complicated, that they couldn't make accurate predictions and that the models all made "embarrassingly" poor predictions as you write, then why is there such a strong, nearly unanimous consensus that human beings are causing global warming? Why is there the same near-unanimous agreement on the degree and range of consequences that will occur as a result?
They wouldn't make statements of such clear certainty if they didn't know, or if the models were so poor. Maybe you're right though, maybe they're *all* deceiving themselves or lying to the public for some hidden agenda.
Climate science automatically attracts people who believe that the climate is greatly affected by human activities. Making a career out of trying to show effects of paramount importance makes much more sense than devoting decades of study to disprove something you find questionable. It is hardly surprising that most climate scientists are positive to idea of human activities affecting the climate. You will similarly find that most astrologers believe that constellations affect people's destinies. Consensus, by itself, means very little.
Holy fallacious analogy, Batman - astrology is not a science, in case you didn't know. The reason climate scientists believe the Earth is getting warmer because of human activity is that the evidence, and the scientific studies on the subject, overwhelmingly point to it being the case. And consensus does mean something (although it is certainly not a guarantee for truth) when it is about interpretation of data and scientific rigor.
I pointed out why consensus does not guarantee scientific validity, both with the example of astrology and an example of psychology, which is indeed a science. The analogy isn't supposed to be an exact match, it is merely supposed to show that the argument from consensus - which is a fallacy - does not hold up.
I never said that consensus guaranteed scientific validity - in fact, I wrote the opposite: "[consensus] is certainly not a guarantee for truth". What I said was that the analogy you were making with astrology to argue that it was "hardly surprising that most climate scientists are positive to idea of human activities affecting the climate" was completely fallacious. Indeed, the reason "most astrologers believe that constellations affect people's destinies" is a shared belief, arguably pre-existing, unrelated to evidence. The reason climate scientists believe that human activity is affecting average temperatures, meanwhile, is rooted in data and rigorous analysis of the data.
I disagree that there is any fallacy.The astrology example shows why consensus by itself is insufficient. The priming paper from psychology shows why consensus in a peer-reviewed scientific community analyzing data is also insufficient. I agree that climate scientists are doing scientific work, but I don't think they understand the systems they are modeling well enough to make their predictions trustworthy.
Of course, climate skeptics will usually always aim for the messenger and the predictions (which, by the way, are made with ceteris paribus assumptions) because they're usually completely unable to dispute the actual data and scientific studies which show that:
I am pointing out why climate scientists are well-educated professionals who have studied this topic for decades, should be viewed with some skepticism. The argument from authority is, fundamentally, about the reliability of the scientists. This has nothing to do with shooting the messenger.
On August 21 2013 15:07 Darkwhite wrote: I will be done shooting the messenger whenever people stop arguing from authority.
First, an argument from authority is not necessarily a fallacy. Second, like I wrote in my first post, I am not arguing that the two propositions I put forward in my previous post (1. the Earth has steadily been getting warmer since the 19th century and 2. human activity is almost certainly the driving cause) are true because scientists say they're true - I'm defending their validity because the data and rigorous scientific analysis of the data point towards them being true. Third, my reply stemmed from your statement that "consensus, by itself, means very little". The point is that 1) The consensus we're talking about here is not "by itself", it's like I said based on robust data and data analysis 2) The consensus we're talking about does hold more weight than complete disagreement among the scientific community, even though like we mentioned it's not a guarantee for truth.
Argument from authority is not explicitly a fallacy, but it depends on the reliability of said authority - discussion of which you like to paint as shooting the messenger. I literally couldn't care less what you pretend to be arguing right now, if you read the post I was actually replying to with the so called fallacy, that post made argument from a combination of authority and consensus. It is reproduced below, though you could just expand the nested quotes too.
As Gringo pointed out, most climate scientists are actually trained physicists. If their field really was so complicated, that they couldn't make accurate predictions and that the models all made "embarrassingly" poor predictions as you write, then why is there such a strong, nearly unanimous consensus that human beings are causing global warming? Why is there the same near-unanimous agreement on the degree and range of consequences that will occur as a result?
They wouldn't make statements of such clear certainty if they didn't know, or if the models were so poor. Maybe you're right though, maybe they're *all* deceiving themselves or lying to the public for some hidden agenda.
1) the Earth has steadily been getting warmer since the 19th century 2) human activity is almost certainly the driving cause
Instead of making fallacious analogies to social sciences, how about you tell us with which part of the data & the scientific analyses behind these two statements you disagree?
The first is true, and a simple matter of reading data. The second is speculation about the causes of observed effects in a complicated system. There is certainly a component to climate change entirely unrelated to human activity, and it is far from settled which one is the dominant. My specific disagreement, though, is with neither of these two claims, but rather about the reliability of: - projected climate changes fifty plus years into the future - the supposedly catastrophic consequences of these changes
Why would you say it is "far from settled"? What are you basing that claim on?
I have also claimed, specifically, that there have been worrisome discpreancies between predictions and actual developments. A graph showing disagreement between temperature increase projections and the actual behavior of nature was posted earlier, which is reproduced below. I would like to hear why this keeps happening, and how this is consistent with the idea that people need to shut up and trust the research: Maybe this isn't even one of the accepted models - I honestly don't know.
As GreenGringo pointed out, the "actual" line falls within the confidence interval on the graph, and as dabbeljuh mentioned, prediction failures have been overstated. Regardless, my reply was not about predictions but about the points I mentioned earlier.
The line just barely falls within their five percent confidence. Given their wide confidence intervals, it is nearly impossible to be any more wrong that this in five years.
On August 22 2013 02:12 Judicator wrote: Not to comment on the actual discussion, but about your faith in the peer review process...you would be surprised at the amount of pretty shitty twiddling of free variables that make it to publication. Justifications are given some times, but alternatives are not, aka what would the model look like with a different set of free variables.
Not really. I've had papers rejected for far more nitpicky reasons than a content-free theory whose free variables are tweaked in an arbitrary and ad hoc way to fit to the data. That is the experience of most scientists. The peer review process is stringent. Commit a howler like that and your competitors to scientific glory will seize upon it and make you look like an idiot.
On August 22 2013 02:12 Judicator wrote:Now as a reader/peer what can you do to get to the bottom of it? Go read the paper(s) itself. Otherwise your doubt that "such a procedure" is completely pointless to what Darkwhite wrote, it doesn't matter if YOU believe the methods are biased (pro tip: a lot of science is belief driven), what matters is if Darkwhite's questioning of model validity is based in something substantial.
So I'm supposed to read every link posted by every denialist on a forum? No. The burden of proof is on HIM, not on me for subscribing to the overwhelming consensus of climate scientists, borne out by all kinds of disparate and mutually reinforcing evidence they have.
We have a professional climate scientist in this thread and if Darkwhite is curious about the tweaking of free variables he could simply have asked Dabbeljuh.
On August 22 2013 02:12 Judicator wrote:The concept of the 5% significance itself is a joke when 20 years or so ago in academia, the gold standard was 10%. So actually go look at some of the methodologies being used, and then comment. Darkwhite reads like he has to some extent, others do not.
And if you read my post, you'll see that that wasn't even a part of the objection. I couldn't care if the projection falls outside the confidence interval altogether as long as it does only a local scale. It's not the job of ANY theory in science to explain every every anomaly and every fluctuation that occurs on a graph.
I'm on your side here, but you aren't understanding how the burden of proof works. You're saying that the burden of proof is on him, and thats true, but if he provides a bunch of sources then that IS his proof. You don't have to read them if you don't want, but you can't go around saying hes got no proof when you just don't want to read the proof he is providing.
No, I'm afraid the tactic of referring to a large study and making vague claims about it is not an honest debating technique even between scholars who CAN be relied on to read the studies.
In a forum like this it is utterly inappropriate. Because frankly, lots of people who do it in forums haven't read the papers they refer to. They're merely pretending to have read stuff. Anyone can do it. A 14-year-old who doesn't know Newton's laws could come in here and post a link to an arcane paper and assure us that he's read it.
If he's going to claim that they tweaked the free variables to fit the data, then I want proof. Which particular study does it? On what page do they make it clear?
I am not expecting you to read a study. Someone else posted a single graph, and I wanted to discuss what the results meant. I also provided a source for my guess that the model was designed in 2008, such that everything up to this point is post hoc fitting, while the rest are predictions. If you insist to keep the discussion entirely free of results and data, we'll be left with nothing but peacocking.
I did not intend to specifically claim that they have fitted entirely free variables. I meant to say that any idiot can give you a perfectly backwards fitted curve in five minutes by Fourier expansion, and that for this reason, I consider the post hoc extremely weak evidence, particularly when the forwards fit is poor.
I assume everybody would find it much less impressive if, today I produced a model which matched the results of Premier League 2008-09 very well, than if I made predictions for 2014-15 which later turned out accurate. The first of these would prove nearly nothing, whereas the second would give you a real reason to trust my model.
On August 22 2013 00:20 Darkwhite wrote: You do understand that the predictions of the model were not made in 1950? As far as I have been able to figure out, this particular model was designed in 2008, but I might be misinterpreting something. I hope the Intergovernmental Panel on Climate Change are recognized as serious: http://cmip-pcmdi.llnl.gov/cmip5/ If I understand the data correctly, the relatively good match from 1950-2008 is a trivial matter of backwards fitting, which is merely a question of how many free variables you make room for and says very little about the validity of the model. On the other hand, in the five years since 2008, the only period for which we are actually comparing predictions and results, there is a very significant discrepancy, such that we currently are at the very border of the 5%-significance level. Is any of this incorrect?
Yes, most of it. As I mentioned in my earlier post (where you dismissed the technical aspects as not so important), those runs are not backwards fitted (btw fitting in a highly nonlinear high dimensional system with models that are incredibly expensive to run is not as trivial as a polynomial fit, it is a challenge, though). They are started as free running runs in 1850 from non initialised equilibrium runs. While some mean quantities are fitted in the model construction process, things like the warming in the 20C are not. This is a model response. the full behaviour in the 20C can be used as a test, not only starting from 2003. The only difference is the forcing (i.e., the model inputs): from 1850 to 2001 it is "observed", from 2001 onwards it is projected. This does not really matter for the short period, though. It is amazing that the model runs are so close to reality (or better, that reality behaves so much like the ensemble mean.), some of that can be explained by the anomaly reference period of 1960-1980 (in this period by construction the anomalies are zero for all runs and reality). It is expected and correct behaviour that reality will over and undershoot the xx% signifinance interval of the multimodel ensemble - for 100-xx% of the time.
The difference is that any number of variables in the model is tweaked and any number of terms are included or excluded on the basis of whether it produces a decent match with the historical data. This invalidates the match, for this period, as proof of accuracy. In the language of machine learning, you are claiming your model's match with the training data as proof of its validity, even in the face of its failures with the test data. There is nothing amazing about managing to overfit a model to the training data, it's just a common mistake.
I have no problem with the technical parts, though I honestly don't consider them relevant. If the best models climate science can deliver keep making poor predictions, even in the very short term of five to ten years, this raises serious doubts about the validity of their long term warming predictions.
its a pity that you dont consider them relevant, as they are for understanding the peculiarities of the climate system.
For example, contrary to intuition, It is much harder to do shortterm then longterm. I know the metaphor is old, but imagine a hot pot of water. It is easy to predict that it will boil after a certain while of increased radiative forcing, it is however physically impossible to predict when and where the first bubbles will appear. Chaotic properties of the climate system _prevent_ exact predictions, the only thing that people can do with models are probabilistic expectations. Given a million Earths, we expect with our current models that - on average - they would warm as the ensemble mean. It is physically and mathematically impossible to predict the singular trajectory of the system beyond its "memory" ... while it is possible to predict, that a change in boundary conditions will lead to a change in mean behaviour after a while, when the forced change is bigger than natural variability (see again detection and attribution).
There are cases where the short term is more difficult to predict than the long term. A good example would be the average of die rolls. Your example with the hot pot of water is, however, not as much old as it is completely wrong. It compares predicting completely different events, both in the long term. Water bubbling is mostly local behavior, though dependent on the temperature of the system, whereas temperature is largely unlocalized because water conducts heat very well.
However, there are also cases where the long term is more difficult to predict than the short term. In fact, these are much more common overall. You will notice that meteorologists can predict the daily weather fairly well on the weekly horizon, because any number of difficult effects become negligible in this perspective, while longer term predictions of the daily weather are extremely unreliable.
It is far from obvious that climate projections will be more accurate in the extreme long term than in the short term. It does, however, mean that any models are left with zero burden of proof. Backwards matching is essentially a given, because no scientist will place his trust in a model which contradicts whatever has already happened and extra terms will always be enough to fix this. Short term predictive accuracy is off the table by fiat, because this is allegedly too chaotic to predict. And long term predictive accuracy is also off the table, because the data won't be here for another fifty years.
At this point, the hypotheses are practically unfalsifiable and barely even science. Whatever does not directly address this is mostly irrelevant excuses.
On August 20 2013 05:08 TricksAre4Figs wrote: Now, having said that, we know that 99% of people are scientifically illiterate and cannot interpret data themselves. We must rely on those professionals who study the field to give their best interpretations. If there is never a debate on the issue and only one side is allowed to speak then I'm afraid I can't believe they are telling the whole truth. A dissenting opinion must be allowed to make it's case in order for the truth to come out.
Imagine if astronomers discovered an asteroid heading toward Earth. They checked their calculations, double-checked them, triple-checked them. Every time they found that Earth is in the path of trajectory of the asteroid.
In that circumstance would you jump up and make a big song and dance about "dissenting opinion"? If you did, would you be surprised if you tested the patience of most astronomers?
The problem is that climate science neither has nor deserves the same level of trust as physics. Climate science is largely in the business of making poorly based claims about the far future while consistently having their models contradicted by the short term developments. Climate science should be lumped with economics and psychology, other fields which similarly apply naive models to much too complicated systems and pretend they have the scientific rigor of a natural science.
As Gringo pointed out, most climate scientists are actually trained physicists. If their field really was so complicated, that they couldn't make accurate predictions and that the models all made "embarrassingly" poor predictions as you write, then why is there such a strong, nearly unanimous consensus that human beings are causing global warming? Why is there the same near-unanimous agreement on the degree and range of consequences that will occur as a result?
They wouldn't make statements of such clear certainty if they didn't know, or if the models were so poor. Maybe you're right though, maybe they're *all* deceiving themselves or lying to the public for some hidden agenda.
Climate science automatically attracts people who believe that the climate is greatly affected by human activities. Making a career out of trying to show effects of paramount importance makes much more sense than devoting decades of study to disprove something you find questionable. It is hardly surprising that most climate scientists are positive to idea of human activities affecting the climate. You will similarly find that most astrologers believe that constellations affect people's destinies. Consensus, by itself, means very little.
Holy fallacious analogy, Batman - astrology is not a science, in case you didn't know. The reason climate scientists believe the Earth is getting warmer because of human activity is that the evidence, and the scientific studies on the subject, overwhelmingly point to it being the case. And consensus does mean something (although it is certainly not a guarantee for truth) when it is about interpretation of data and scientific rigor.
I pointed out why consensus does not guarantee scientific validity, both with the example of astrology and an example of psychology, which is indeed a science. The analogy isn't supposed to be an exact match, it is merely supposed to show that the argument from consensus - which is a fallacy - does not hold up.
I never said that consensus guaranteed scientific validity - in fact, I wrote the opposite: "[consensus] is certainly not a guarantee for truth". What I said was that the analogy you were making with astrology to argue that it was "hardly surprising that most climate scientists are positive to idea of human activities affecting the climate" was completely fallacious. Indeed, the reason "most astrologers believe that constellations affect people's destinies" is a shared belief, arguably pre-existing, unrelated to evidence. The reason climate scientists believe that human activity is affecting average temperatures, meanwhile, is rooted in data and rigorous analysis of the data.
I disagree that there is any fallacy.The astrology example shows why consensus by itself is insufficient. The priming paper from psychology shows why consensus in a peer-reviewed scientific community analyzing data is also insufficient. I agree that climate scientists are doing scientific work, but I don't think they understand the systems they are modeling well enough to make their predictions trustworthy.
Your astrology analogy implied that there was a consensus among climate scientists because of pre-existing beliefs, while I've repeatedly explained to you why pre-existing beliefs are not the reason for the existence of the consensus among climate scientists. Regarding the psychology analogy, 1) climate science is not a social science 2) I already explicitly said that I did not consider the consensus to be sufficient. If you "don't think" they understand the systems well enough, show us which part of their developments you have doubts about, not simply a graph in which the temperatures of a few years are close to the limit of the confidence interval.
Of course, climate skeptics will usually always aim for the messenger and the predictions (which, by the way, are made with ceteris paribus assumptions) because they're usually completely unable to dispute the actual data and scientific studies which show that:
I am pointing out why climate scientists are well-educated professionals who have studied this topic for decades, should be viewed with some skepticism. The argument from authority is, fundamentally, about the reliability of the scientists. This has nothing to do with shooting the messenger.
On August 21 2013 15:07 Darkwhite wrote: I will be done shooting the messenger whenever people stop arguing from authority.
First, an argument from authority is not necessarily a fallacy. Second, like I wrote in my first post, I am not arguing that the two propositions I put forward in my previous post (1. the Earth has steadily been getting warmer since the 19th century and 2. human activity is almost certainly the driving cause) are true because scientists say they're true - I'm defending their validity because the data and rigorous scientific analysis of the data point towards them being true. Third, my reply stemmed from your statement that "consensus, by itself, means very little". The point is that 1) The consensus we're talking about here is not "by itself", it's like I said based on robust data and data analysis 2) The consensus we're talking about does hold more weight than complete disagreement among the scientific community, even though like we mentioned it's not a guarantee for truth.
Argument from authority is not explicitly a fallacy, but it depends on the reliability of said authority - discussion of which you like to paint as shooting the messenger.
The reason I paint it that way is because I have yet to see a single argument or piece of evidence which legitimately puts doubts over the qualifications of the entire community of scientists which agree over the two propositions I mentioned. If your argument is only that "consensus doesn't imply truth", then we agree and I already addressed that. The attacks on the said scientific community have however gone way beyond that over the last few pages.
On August 22 2013 21:23 Darkwhite wrote: I literally couldn't care less what you pretend to be arguing right now, if you read the post I was actually replying to with the so called fallacy, that post made argument from a combination of authority and consensus. It is reproduced below, though you could just expand the nested quotes too.
I'm not "pretending" to be arguing anything - I am arguing the points I mentioned. In case you didn't notice, I'm a different poster than the one you initially replied to, and if you don't want to discuss what I raised then don't reply to me. Also, I replied to aspects of your post that went beyond "consensus does not equate truth".
1) the Earth has steadily been getting warmer since the 19th century 2) human activity is almost certainly the driving cause
Instead of making fallacious analogies to social sciences, how about you tell us with which part of the data & the scientific analyses behind these two statements you disagree?
The first is true, and a simple matter of reading data. The second is speculation about the causes of observed effects in a complicated system. There is certainly a component to climate change entirely unrelated to human activity, and it is far from settled which one is the dominant. My specific disagreement, though, is with neither of these two claims, but rather about the reliability of: - projected climate changes fifty plus years into the future - the supposedly catastrophic consequences of these changes
Why would you say it is "far from settled"? What are you basing that claim on?
I have also claimed, specifically, that there have been worrisome discpreancies between predictions and actual developments. A graph showing disagreement between temperature increase projections and the actual behavior of nature was posted earlier, which is reproduced below. I would like to hear why this keeps happening, and how this is consistent with the idea that people need to shut up and trust the research: Maybe this isn't even one of the accepted models - I honestly don't know.
As GreenGringo pointed out, the "actual" line falls within the confidence interval on the graph, and as dabbeljuh mentioned, prediction failures have been overstated. Regardless, my reply was not about predictions but about the points I mentioned earlier.
The line just barely falls within their five percent confidence. Given their wide confidence intervals, it is nearly impossible to be any more wrong that this in five years.
dabbeljuh replied to that earlier on, so I'm just going to direct you to his post. Also, you did not reply to my question "Why would you say it is "far from settled"? What are you basing that claim on?".
On August 20 2013 05:08 TricksAre4Figs wrote: Now, having said that, we know that 99% of people are scientifically illiterate and cannot interpret data themselves. We must rely on those professionals who study the field to give their best interpretations. If there is never a debate on the issue and only one side is allowed to speak then I'm afraid I can't believe they are telling the whole truth. A dissenting opinion must be allowed to make it's case in order for the truth to come out.
Imagine if astronomers discovered an asteroid heading toward Earth. They checked their calculations, double-checked them, triple-checked them. Every time they found that Earth is in the path of trajectory of the asteroid.
In that circumstance would you jump up and make a big song and dance about "dissenting opinion"? If you did, would you be surprised if you tested the patience of most astronomers?
The problem is that climate science neither has nor deserves the same level of trust as physics. Climate science is largely in the business of making poorly based claims about the far future while consistently having their models contradicted by the short term developments. Climate science should be lumped with economics and psychology, other fields which similarly apply naive models to much too complicated systems and pretend they have the scientific rigor of a natural science.
As Gringo pointed out, most climate scientists are actually trained physicists. If their field really was so complicated, that they couldn't make accurate predictions and that the models all made "embarrassingly" poor predictions as you write, then why is there such a strong, nearly unanimous consensus that human beings are causing global warming? Why is there the same near-unanimous agreement on the degree and range of consequences that will occur as a result?
They wouldn't make statements of such clear certainty if they didn't know, or if the models were so poor. Maybe you're right though, maybe they're *all* deceiving themselves or lying to the public for some hidden agenda.
Climate science automatically attracts people who believe that the climate is greatly affected by human activities. Making a career out of trying to show effects of paramount importance makes much more sense than devoting decades of study to disprove something you find questionable. It is hardly surprising that most climate scientists are positive to idea of human activities affecting the climate. You will similarly find that most astrologers believe that constellations affect people's destinies. Consensus, by itself, means very little.
A fine example of scientific consensus gone wrong is given below. It details how a very influential priming experiment, which has been cited thousands of times in psychology papers, has probably been a false positive all along. Note that this is a very simple and straightforward experiment, which can be replicated on a budget of less than ten thousand dollars, and the original paper is from 1996. http://chronicle.com/article/Power-of-Suggestion/136907/
Plenty of scientists in all fields - particularly the ones who make headlines in the media - make very bold claims with very dubious evidence. The only vaccine against false prophets is continuous and rigorous experimental verification, which is precisely the thing which is nearly impossible in climate science. The only way to test the accuracy of your models is to wait for the years to tick by. Historically, the short-term accuracy has been terrible, which leaves very little credibility for the long term projections.
I won't bother replying to or quoting the last half of your post, which is desperately arguing against claims I have never made. My position is simply to regard climate science with the same sort of moderate skepticism as economics and psychology. All these sciences generally deal with much more complicated systems than physics and cannot test their models with the same relative ease, and also have much less stellar credentials.
You are doing more than just expressing skepticism though, you are effectively saying that nearly all climate scientists are wrong to have any confidence in the predictions they're making because their models are too poor to be taken seriously in the short term (~5 years), much less the long term, which is a very significant claim.
My only concern is that you seem to be making these comments without having any real expertise in climate science. You may have some understanding on how modelling data works, but I don't think that its really sufficient for you to absolutely say that the entire field should be considered as relatively non-rigorous, and largely equivalent to economics or psychology. What appears obvious from your perspective may be invalid in the presence of complementary data (as dabbeljuh points out there are many different lines of evidence that show the general trend).
What I would suggest is that you not make such definitive claims before engaging in a proper debate with a real climate scientist (as you are doing now). If your comment was more along the lines of "How can I trust climate science when their modelling is shown to consistently provide false predictions in the near and long term?" that would be fine, but instead you seem to be going beyond that and making authoritative claims, which is what I take issue with.
Also I suppose you are right in that it is possible for the entire field of scientists to be exhibiting a sort of "priming" effect as your article references (I haven't read it fully yet but I will), but it would be good to recognize that the same psychological effects which made astrology widely accepted would be much harder to reproduce today in the face of modern scientific scrutiny. That's why I think that all of this is highly unlikely. I'm sure there could be some problems with regard to certain studies, but on such a large scale amongst (tens of thousands? not sure) of scientists all cross-checking each other and verifying data, its very difficult to believe that effects like group think or priming are having such misleading effects. Not to say its impossible or anything.
On August 20 2013 05:08 TricksAre4Figs wrote: Now, having said that, we know that 99% of people are scientifically illiterate and cannot interpret data themselves. We must rely on those professionals who study the field to give their best interpretations. If there is never a debate on the issue and only one side is allowed to speak then I'm afraid I can't believe they are telling the whole truth. A dissenting opinion must be allowed to make it's case in order for the truth to come out.
Imagine if astronomers discovered an asteroid heading toward Earth. They checked their calculations, double-checked them, triple-checked them. Every time they found that Earth is in the path of trajectory of the asteroid.
In that circumstance would you jump up and make a big song and dance about "dissenting opinion"? If you did, would you be surprised if you tested the patience of most astronomers?
The problem is that climate science neither has nor deserves the same level of trust as physics. Climate science is largely in the business of making poorly based claims about the far future while consistently having their models contradicted by the short term developments. Climate science should be lumped with economics and psychology, other fields which similarly apply naive models to much too complicated systems and pretend they have the scientific rigor of a natural science.
As Gringo pointed out, most climate scientists are actually trained physicists. If their field really was so complicated, that they couldn't make accurate predictions and that the models all made "embarrassingly" poor predictions as you write, then why is there such a strong, nearly unanimous consensus that human beings are causing global warming? Why is there the same near-unanimous agreement on the degree and range of consequences that will occur as a result?
They wouldn't make statements of such clear certainty if they didn't know, or if the models were so poor. Maybe you're right though, maybe they're *all* deceiving themselves or lying to the public for some hidden agenda.
Climate science automatically attracts people who believe that the climate is greatly affected by human activities. Making a career out of trying to show effects of paramount importance makes much more sense than devoting decades of study to disprove something you find questionable. It is hardly surprising that most climate scientists are positive to idea of human activities affecting the climate. You will similarly find that most astrologers believe that constellations affect people's destinies. Consensus, by itself, means very little.
A fine example of scientific consensus gone wrong is given below. It details how a very influential priming experiment, which has been cited thousands of times in psychology papers, has probably been a false positive all along. Note that this is a very simple and straightforward experiment, which can be replicated on a budget of less than ten thousand dollars, and the original paper is from 1996. http://chronicle.com/article/Power-of-Suggestion/136907/
Plenty of scientists in all fields - particularly the ones who make headlines in the media - make very bold claims with very dubious evidence. The only vaccine against false prophets is continuous and rigorous experimental verification, which is precisely the thing which is nearly impossible in climate science. The only way to test the accuracy of your models is to wait for the years to tick by. Historically, the short-term accuracy has been terrible, which leaves very little credibility for the long term projections.
I won't bother replying to or quoting the last half of your post, which is desperately arguing against claims I have never made. My position is simply to regard climate science with the same sort of moderate skepticism as economics and psychology. All these sciences generally deal with much more complicated systems than physics and cannot test their models with the same relative ease, and also have much less stellar credentials.
You are doing more than just expressing skepticism though, you are effectively saying that nearly all climate scientists are wrong to have any confidence in the predictions they're making because their models are too poor to be taken seriously in the short term (~5 years), much less the long term, which is a very significant claim.
My only concern is that you seem to be making these comments without having any real expertise in climate science. You may have some understanding on how modelling data works, but I don't think that its really sufficient for you to absolutely say that the entire field should be considered as relatively non-rigorous, and largely equivalent to economics or psychology. What appears obvious from your perspective may be invalid in the presence of complementary data (as dabbeljuh points out there are many different lines of evidence that show the general trend).
What I would suggest is that you not make such definitive claims before engaging in a proper debate with a real climate scientist (as you are doing now). If your comment was more along the lines of "How can I trust climate science when their modelling is shown to consistently provide false predictions in the near and long term?" that would be fine, but instead you seem to be going beyond that and making authoritative claims, which is what I take issue with.
Also I suppose you are right in that it is possible for the entire field of scientists to be exhibiting a sort of "priming" effect as your article references (I haven't read it fully yet but I will), but it would be good to recognize that the same psychological effects which made astrology widely accepted would be much harder to reproduce today in the face of modern scientific scrutiny. That's why I think that all of this is highly unlikely. I'm sure there could be some problems with regard to certain studies, but on such a large scale amongst (tens of thousands? not sure) of scientists all cross-checking each other and verifying data, its very difficult to believe that effects like group think or priming are having such misleading effects. Not to say its impossible or anything.
So, you agree that consensus is not sufficient, yet you feel obliged to spout nonsense like holy fallacious analogy, Batman when I point it out, and instead of redacting this you hide behind the defense that it's not what you're discussing.
I wanted to get the arguments from consensus and authority out of the way first, before moving on to the part where predictions don't match reality, but that's been going on in parallel with dabbeljuh anyway, which is why I haven't been explicit about it in direct replies to you.
On August 20 2013 05:08 TricksAre4Figs wrote: Now, having said that, we know that 99% of people are scientifically illiterate and cannot interpret data themselves. We must rely on those professionals who study the field to give their best interpretations. If there is never a debate on the issue and only one side is allowed to speak then I'm afraid I can't believe they are telling the whole truth. A dissenting opinion must be allowed to make it's case in order for the truth to come out.
Imagine if astronomers discovered an asteroid heading toward Earth. They checked their calculations, double-checked them, triple-checked them. Every time they found that Earth is in the path of trajectory of the asteroid.
In that circumstance would you jump up and make a big song and dance about "dissenting opinion"? If you did, would you be surprised if you tested the patience of most astronomers?
The problem is that climate science neither has nor deserves the same level of trust as physics. Climate science is largely in the business of making poorly based claims about the far future while consistently having their models contradicted by the short term developments. Climate science should be lumped with economics and psychology, other fields which similarly apply naive models to much too complicated systems and pretend they have the scientific rigor of a natural science.
As Gringo pointed out, most climate scientists are actually trained physicists. If their field really was so complicated, that they couldn't make accurate predictions and that the models all made "embarrassingly" poor predictions as you write, then why is there such a strong, nearly unanimous consensus that human beings are causing global warming? Why is there the same near-unanimous agreement on the degree and range of consequences that will occur as a result?
They wouldn't make statements of such clear certainty if they didn't know, or if the models were so poor. Maybe you're right though, maybe they're *all* deceiving themselves or lying to the public for some hidden agenda.
Climate science automatically attracts people who believe that the climate is greatly affected by human activities. Making a career out of trying to show effects of paramount importance makes much more sense than devoting decades of study to disprove something you find questionable. It is hardly surprising that most climate scientists are positive to idea of human activities affecting the climate. You will similarly find that most astrologers believe that constellations affect people's destinies. Consensus, by itself, means very little.
A fine example of scientific consensus gone wrong is given below. It details how a very influential priming experiment, which has been cited thousands of times in psychology papers, has probably been a false positive all along. Note that this is a very simple and straightforward experiment, which can be replicated on a budget of less than ten thousand dollars, and the original paper is from 1996. http://chronicle.com/article/Power-of-Suggestion/136907/
Plenty of scientists in all fields - particularly the ones who make headlines in the media - make very bold claims with very dubious evidence. The only vaccine against false prophets is continuous and rigorous experimental verification, which is precisely the thing which is nearly impossible in climate science. The only way to test the accuracy of your models is to wait for the years to tick by. Historically, the short-term accuracy has been terrible, which leaves very little credibility for the long term projections.
I won't bother replying to or quoting the last half of your post, which is desperately arguing against claims I have never made. My position is simply to regard climate science with the same sort of moderate skepticism as economics and psychology. All these sciences generally deal with much more complicated systems than physics and cannot test their models with the same relative ease, and also have much less stellar credentials.
You are doing more than just expressing skepticism though, you are effectively saying that nearly all climate scientists are wrong to have any confidence in the predictions they're making because their models are too poor to be taken seriously in the short term (~5 years), much less the long term, which is a very significant claim.
My only concern is that you seem to be making these comments without having any real expertise in climate science. You may have some understanding on how modelling data works, but I don't think that its really sufficient for you to absolutely say that the entire field should be considered as relatively non-rigorous, and largely equivalent to economics or psychology. What appears obvious from your perspective may be invalid in the presence of complementary data (as dabbeljuh points out there are many different lines of evidence that show the general trend).
What I would suggest is that you not make such definitive claims before engaging in a proper debate with a real climate scientist (as you are doing now). If your comment was more along the lines of "How can I trust climate science when their modelling is shown to consistently provide false predictions in the near and long term?" that would be fine, but instead you seem to be going beyond that and making authoritative claims, which is what I take issue with.
Also I suppose you are right in that it is possible for the entire field of scientists to be exhibiting a sort of "priming" effect as your article references (I haven't read it fully yet but I will), but it would be good to recognize that the same psychological effects which made astrology widely accepted would be much harder to reproduce today in the face of modern scientific scrutiny. That's why I think that all of this is highly unlikely. I'm sure there could be some problems with regard to certain studies, but on such a large scale amongst (tens of thousands? not sure) of scientists all cross-checking each other and verifying data, its very difficult to believe that effects like group think or priming are having such misleading effects. Not to say its impossible or anything.
I am saying that the results I have seen are not enough to place trust in either their projections for climate change nor their calls for policy revision. I really don't see why you take offense at having climate science compared to economics or psychology. Both are legitimate sciences, they just happen to dealing with extremely complicated systems, which sets them very firmly apart from the reliability of the more familiar parts of physics, such as gravity and astronomy.
If you think this is too definite a claim for a well-educated physicist to make, then we'll just have to disagree.
I have never said climate science suffers from priming - the link details how one of the progenitor experiments of priming is probably a false positive. You really need to spend less time making false inferences about what I'm writing.
Nobody knows if the net effects would be good or bad, and probably nobody can know. We are talking, after all, about effects across the world over a century. How accurately could somebody in 1900 have predicted what would matter to human life in 2000? What reason do we have to think we can do better?
Should we, for instance, assume that Bangladesh will still be a poor country a century hence, or that it will by then have followed the path blazed by South Korea, Taiwan, Singapore and Hong Kong—and so be in a position to dike its coast, as Holland did several centuries ago, or move housing some miles further inland, at a cost that can be paid out of petty change? Should we assume that population increase makes agricultural land more valuable and the expansion of the area over which crops can be grown more important, or that improvements in crop yield make it less? While there may be people who believe that they know the answer to such questions, the numbers required to justify such belief are at best educated guesses, in most cases closer to pure invention. Someone who wants to prove that global warming is bad can make high estimates for the costs, low estimates for the benefits, and so prove his case to his own satisfaction. Someone with the opposite agenda can reverse the process and prove his case equally well.
If we cannot calculate in any detail what the actual consequences of global warming and associated costs and benefits will be, an alternative is to ask whether we have any reason to expect, a priori, that costs will be larger than benefits. There are, I think, two answers.
The first is that any change, whether warming or cooling, is presumptively bad, because current human activity is optimized against current conditions. Farmers grow crops suited to the climate where they are growing them; a change in climate will require a costly change in what they grow and how they grow it. Houses are designed for the climate they are built in and located in places not expected, under current circumstances, to flood. Putting it in economic terms, we have born sunk costs based on the current environment, and a change in that environment will eliminate some of the quasi-rents that we expected as the return for those costs.
This is a real argument against rapid change. But the global warming controversy involves changes over not a year or a decade but a century. Over a century, most farmers will change the crop they find it most profitable to grow multiple times; if average temperatures are trending up, those changes will include a shift towards crops better suited to slightly warmer weather. Over a century, most houses will be torn down and replaced; if sea level is rising, houses currently built on low lying coastal ground will be rebuilt a little farther inland—not much farther if we are talking, as the IPCC estimates suggest we should be, about a rise of a foot or two. Hence the presumption that change is bad is a very weak one for changes as slow as those we have good reason to expect from global warming.
It is hard to see any other reason to expect gobal warming to make us, on net, worse off. The earth and its climate were not, after all, designed for our convenience, so there is no good reason to believe that their current state is optimal for us. It is true that our species evolved to survive under then existing climatic conditions but, over the period for which humans have existed, climate has varied by considerably more than the changes being predicted for global warming. And, for the past many thousands of years, humans have lived and prospered over a range of climates much larger than the range that we expect the climate at any particular location to change by.
If we have no good reason to believe that humans will be substantially worse off after global warming than before, we have no good reason to believe that it is worth bearing sizable costs to prevent global warming.
I am saying that the results I have seen are not enough to place trust in either their projections for climate change nor their calls for policy revision. I really don't see why you take offense at having climate science compared to economics or psychology. Both are legitimate sciences, they just happen to dealing with extremely complicated systems, which sets them very firmly apart from the reliability of the more familiar parts of physics, such as gravity and astronomy.
If you think this is too definite a claim for a well-educated physicist to make, then we'll just have to disagree.
I have never said climate science suffers from priming - the link details how one of the progenitor experiments of priming is probably a false positive. You really need to spend less time making false inferences about what I'm writing.
I agree that climate science differs from a "clear" natural science as gravity or astronomy, I dont agree that you can directly compare it to economics and psychology. The reasons have been mentioned above, the root of climate sciences are physics, observations and reproducable and falsifiable hypotheses. I fear that you and I will not agree on that topic in this thread. But believe me that when I entered this field with a degree in physics and courses in machine learning (which I also enjoyed tremendously), I shared some of your criticisms, and it took a while to get rid of the typical "physicist supremacy dogma" which essentially all physicist share when looking at or entering neighbouring science communities (most of my physicist friends are now in biotech or medicine or nanotech research and they experienced the same feeling whereever they went - so it must clearly be true =) ).
your arguments concerning using training data as verification data are partially warranted, though not completely correct. We as in the climate science community are aware of this problem and try to design tests that are meaningful. I hope you can give thousands of trained physicists and mathematicians the benefit of a doubt, we know of the danger of overfitting since probably the second semester of our respective studies, and try to adress it by developing "independent" tests that do not rely on directly tuned quantities. We know that it would be much cooler to have a 200 year training period and to then verify the models perfectly in the 20C, but unfortunately most observations dont go back longer than 10-50 years, and in extreme simple cases as in temperatures -150 years. This is a challenge for the tuning community.
As I have told you, though, in this thread a couple of times already: the argument that _some_ aspects of some parts of a specific subgroup of climate science are difficult, does not invalidate the full line of evidence in any scientific way. It is only a scientific intellectual challenge to think harder and find better ways to construct and evaluate models in a reasonable way.
Best regards, (btw while I dont agree with most of your point, I feel that your skepticism is based on a healthy respect of how science should work, so I hope you give my arguments also some consideration - we are after all both natural scientists)
So, if you're done shooting at the messenger, could we have a discussion over which part of the data and scientific studies which establish the validity of the two propositions I mentioned you disagree with?
Yup. Pretty much all that needs to be shown on every page. This graph is as real as it gets, raw data measured from 39,000 temperature stations worldwide, no computer models, no predictions, nothing, it is exactly what it shows.
Also keep in mind that when you look at this graph you can see the temperature is not just increasing, it is accelerating. Hypothetically, if the rate became exponential and the temperature doubled each year, and it took 50 years to increase by 1.5C, it won't take another 50 years to increase to +3C, it will take only 1 year.
I don't think you can look at this graph and think that it is going to plummet back to norm any time soon. Of course any science newbie can easily see a trend.
What annoys me most is that subsequent posters seemingly ignore posts even directly above them... -_-
Question: Why does this graph not start much sooner than 1750? What about the Medieval Warming Period? CO2 wasn't responsible for that.
So, if you're done shooting at the messenger, could we have a discussion over which part of the data and scientific studies which establish the validity of the two propositions I mentioned you disagree with?
Yup. Pretty much all that needs to be shown on every page. This graph is as real as it gets, raw data measured from 39,000 temperature stations worldwide, no computer models, no predictions, nothing, it is exactly what it shows.
Also keep in mind that when you look at this graph you can see the temperature is not just increasing, it is accelerating. Hypothetically, if the rate became exponential and the temperature doubled each year, and it took 50 years to increase by 1.5C, it won't take another 50 years to increase to +3C, it will take only 1 year.
I don't think you can look at this graph and think that it is going to plummet back to norm any time soon. Of course any science newbie can easily see a trend.
What annoys me most is that subsequent posters seemingly ignore posts even directly above them... -_-
Question: Why does this graph not start much sooner than 1750? What about the Medieval Warming Period? CO2 wasn't responsible for that.
Here are plots going back further in time. The global mean temperature can indeed fluctuate without significant interference from humans. That's not to say that current trends must not be caused by human activity.
On August 22 2013 21:23 Darkwhite wrote: I am not expecting you to read a study. Someone else posted a single graph, and I wanted to discuss what the results meant. I also provided a source for my guess that the model was designed in 2008, such that everything up to this point is post hoc fitting, while the rest are predictions. If you insist to keep the discussion entirely free of results and data, we'll be left with nothing but peacocking.
I'm sorry, but this is a distortion that is so at odds with the post history in this thread that it verges on deception.
I never said or hinted that I think the discussion should be free of results and data. I only wanted something more concrete to substantiate your claim that climate scientists arrive at their models by twiddling with free variables to retrospectively fit the data.
On August 22 2013 21:23 Darkwhite wrote:I did not intend to specifically claim that they have fitted entirely free variables. I meant to say that any idiot can give you a perfectly backwards fitted curve in five minutes by Fourier expansion, and that for this reason, I consider the post hoc extremely weak evidence, particularly when the forwards fit is poor.
But nobody was TRYING to use that model as evidence for climate change. Rather you were trying to use it as evidence against climate change.
Designing a curve by tweaking arbitrary variables to retrospectively fit the data is such an obvious scientific howler that it seems RIDICULOUS to suggest that climate scientists are doing it. That's why I asked for evidence to support your piece of slander.
By all means continue to use whatever data you like. But don't make claims about it that you know you can't support and don't speculate that climate scientists are incompetent buffoons who use whatever boundary conditions and arbitrary parameters they feel like.
EPT
![[image loading]](http://i.livescience.com/images/i/000/029/506/i02/co2-temperature.jpg?1343734352)
