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I have to ask Haplo, have you ever taken any university level statistics courses? As one of the areas you seem to have some difficulty with is statistics, both as far as interpretation, and understanding why statistics are used in the first place.
The reason I say this is because data recorded in the natural world is by its nature 'noisy' with lots of potential sources of interference which can throw off single measurements. http://www.socialresearchmethods.net/kb/truescor.php Now what scientists do to get around this is to take multiple samples and then average them out to show trends (and hopefully get close to the true score). You will notice that most of the graphs Stealth Hunter has been posting have multiple lines, one being the short term averaged data (monthly, bimonthly, yearly,etc) and the other being the longer term averaged data (3 years, 5 years, 10 years, etc). The longer term stuff is what is used to show a trend as it levels out the ammout of error or noise that occurs sample to sample from natural fluctuation such as solar output. I remember when people were going on about I think it was 2008 being a cooler year than average, and saying that that one year proved global warming was a hoax. The problem though was that was just one year, it could (and was) just be statistical variance (in that case I believe it was due to lower solar output) or natural fluctuations. This is why when looking at trends you average things over longer intervals and over several intervals to see what the overall trend is. Here is some wiki info on solar variation for fun (which is a big factor in actual temperature) http://en.wikipedia.org/wiki/Solar_variation Anyhow, I have to inform you all that I am going to have to back out of this debate for the next month or so. I am in the middle of a major crunch period and will be for the next while (till around late April). I really hate to leave off in the middle of this when I think we have been making some good progress. Once the crunch is over I'll be more then happy to resume the debate then. I may still pop in and make some small comments, but I do not have the time for long rebuttals or any researching into the subject, it is just far to time consuming. I hope you all understand. |
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PS. I think a source of confusion for Haplo is the relationships between pack ice and the rest. He is right I believe in the sense that pack ice (free floating ice that formed from ocean water, in the ocean) will not change the water level if it melts as it displaces an equal volume already as frozen water compared to liquid water.
Problem though is when we introduce sources of ice that originate on land, like glaciers that run into the ocean and produce icebergs and the like. It is the destabilization of land based ice sources like glaciers melting faster then they regrow, that is causing the water level to increase. Especially if temperatures in the antarctic got high enough to cause those glaciers to melt. This is aside of course from all the environmental and weather havoc loosing ice in the north pole would cause. |
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Neon - I took a statistics course - but that was a decade and a half or more ago, and to be honest - your right - it was definitely not the high water mark of my courses that semester.
You take that month off and do what you need to, I will use the time to try and get a better grip on this all - and when you return we will continue. Best of luck and effort to combine for the desired outcome my friend! :yeah: |
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http://www1.lsbu.ac.uk/water/anmlies.html http://antoine.frostburg.edu/chem/se...roperties.html Anyhow thanks for the kind words and understand Stealthunter and CaptainHaplo. It is much appreciated :DL |
Fair enough. I just figured that a tiny change in such a huge non uniform body might be enough to cause larger changes in the total space that water would occupy. Thanks for the answer.
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BY training I'm an astrophysics geek. I'm open to the AGW hypothesis, but I think their current code—only glimpsed because it was leaked in the CRU debacle, they refused to ever actually publish their code—is pretty, um, un-robust. :)
I'd not go out on a limb in either direction, frankly. The notion that industrial output could alter climate is without question plausible, but with respect to policy, it needs to be very well characterized so a cost-benefit analysis can be done. So I'm not in the "hoax" camp, though I remain deeply skeptical. From reading the CRU stuff (admitted by the authors to be entirely real) it is clear that they colluded to not "show their work" via denying FOIA requests, "losing" data, etc. They also clearly work hard to minimize any historical warm periods while cherry-picking to increase recent warming trends in their model. That is something to remember, the very notion of "average temperature" is a statistical construct that requires subjective input in terms of programming. How does one weight temperatures over sea vs land? How does one compare historical temp data collected differently than modern satellite data? How do you calibrate temperature proxies (tree rings, ice cores, and so forth) accurately enough to make claims that can have the temp increase/decrease as some fraction of a degree? I think anyone claiming it's "settled science" in either direction is either intentionally disingenuous or not very smart. This is why when I hear climate scientists talking about things with great certainty I instantly distrust them since I'm used to real scientists putting appropriate (large) error bars on things. (heck, I'm used to being happy with "order of magnitude" level answers :) ). The usual response is that they have to not be so conditional when talking top non-experts. Sorry, but that is activism, not science IMO. If people are too stupid to understand uncertainty, tough, deal with it. By stating something like a tiny temp increase with certainty, you lose a lot of credibility. (there is plenty that CAN be stated with certainty, but the output of a bunch of crap, spaghetti code is not among that set) I remember asking Meave Leakey about a species attribution and lineage to modern man, and really respected her "we simply don't know" answer. |
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A good article about statistics in science.
http://www.sciencenews.org/view/feat...Are,_Its_Wrong Highly relevant to climate science since virtually all the AGW science is entirely predicated on statistical models. Another good article that is a rebuttal to the above: http://motls.blogspot.com/2010/03/de...l-methods.html Note that I think his basic premise that the first author was somehow saying all statistics are bad, or entirely discredit sciences that use it is wrong. I didn't read the first article as more than a cautionary tale that statistics need to be used properly to be meaningful. The 2d article puts by previous post about "not knowing one way or the other" into a clearer light, too. From a policy standpoint, you need to do a cost analysis of doing nothing, doing nothing and later mitigating, or doing whatever the AGW mitigation schemes are. Then, you need to weight them based on a "hard-science" probability of the different models unfolding, as well as the range of outcomes. If the AGW mitigation is not clearly superior, I think it fails the test. The notion that it's better to do something than nothing is false, since in many cases, the idea is that short of some radical change, mitigation actually doesn't do anything (chaotic effects, basically). |
I reserect this thread from its page 3 slumber to bring you yet another refutiation.
http://blogs.news.com.au/heraldsun/a...fore_your_eyes |
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Oh, it means you don't get it at all. All you need to know to see why your "refutation" makes no sense Steamwake is on page 1 of this topic.:down: |
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And my ultra quicky response is that a year (or in this case what looks like a few months) does not a trend make.
Sometimes I think high school should teach statistics relating to science, as that has to be the number one mistake made by non scientists when it comes to them trying to understand scientific data and reasoning, not knowing how to work with statistics or what they mean or indicate. Anyhow. <goes back to work> |
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