Jason
Pluto
May all your hits be crits
Posts: 5,579
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Post by Jason on Jul 21, 2008 20:35:54 GMT -4
Oh yeah. That was totally what I was thinking.
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Post by stutefish on Jul 22, 2008 13:02:21 GMT -4
Oh yeah. That was totally what I was thinking. Heh. That post describes her latest attempt to compare the UN climate model's predicted trend to the trend actually recorded in the real climate over the last eight years. The blog is mostly about her ongoing series of attempts to reconcile these two things (the UN model's predictions and the Earth's actual climate trends). It's a pretty detailed--and highly technical--record of her analysis: Problems, solutions, setbacks, re-evaluations, etc. The comments section for each post is also pretty full of lively debate. There's lot of suggestions for improving the analysis, identification of problems with the data or the assumptions being made, and discussion about ways to get closer to some good statistically valid answers. For what it's worth, her latest attempt--like all the previous ones--generally "falsifies" the UN model, in the sense that it describes a global temperature trend of significantly less than the 2 degrees C per century predicted by the model. But she freely acknowledges--and openly discusses--the limitations of her analysis. Hence the blog: It's a detailed record of her attempts to improve that analysis and arrive at a sound comparison of the model and the real Earth climate.
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Post by Apollo Gnomon on Jul 23, 2008 19:19:26 GMT -4
Calipers are a use OF Vernier scale. A Vernier scale is not calipers.
Which fallacy is the above question? Is that a Red Herring combined with begging the question?
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Post by Apollo Gnomon on Jul 23, 2008 19:41:51 GMT -4
I'll try again. Do you think the Earth's atmosphere is currently experiencing a warming trend? When it comes to whether a global warming trend is actually occurring, I'm an agnostic. There seems to be evidence both for and against a current warming trend, and I am not completely convinced by either side. arctic.atmos.uiuc.edu/cryosphere/IMAGES/sea.ice.anomaly.timeseries.jpgNote the distinct downward trend in arctic sea ice. For the first time since Europeans started sailing in arctic waters, there is a "north west passage." Loss of arctic ice will decrease the amount of heat reflected back into space: www.agu.org/pubs/crossref/1997/97PA00721.shtmlA common type of question about global warming, but irrelevant. An apple is a rose, but a rose is not an apple. What I mean by that is that a hot planet can result from several causes. Pointing to the "end of the Ice Age" (or the various beginnings and and end of various ice ages, large and small) or pointing to a few statistical outliers in the data set of heat-by-year does NOT invalidate the premise that fossil fuel combustion is contributing to change in planetary climate now.
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Jason
Pluto
May all your hits be crits
Posts: 5,579
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Post by Jason on Jul 24, 2008 9:21:28 GMT -4
The standard method of taking a temperature in the ocean in 1860 was to haul a bucket up the side of a ship and stick a thermometer in it. Do you see some possible sources of error with such a method?
Not invalidating a premise is not very strong proof for a premise, is it?
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Post by Apollo Gnomon on Jul 24, 2008 15:44:00 GMT -4
The standard method of taking a temperature in the ocean in 1860 was to haul a bucket up the side of a ship and stick a thermometer in it. Do you see some possible sources of error with such a method? No. Not as described. A few questions would be in order, basically I'd like to know more about the methodology and instrumentation. Does it change the amount of arctic sea ice observed for the last 200+ years?
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Jason
Pluto
May all your hits be crits
Posts: 5,579
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Post by Jason on Jul 24, 2008 16:36:08 GMT -4
First of all, the observations of arctic sea ice 200 years ago can't really be considered accurate. Once weather satellites were in place to observe it then we might consider the records more or less accurate from that point on - say around the 1970s onward. Second, the Antarctic ice has been increasing. Does that mean we're in a phase of global cooling?
Possible errors with the "bucket" method - the bucket will be a different temperature than the sea water both before and after immersion, which will effect the temperature of the water contained in it - wind conditions will have a greater affect on a bucket than on the ocean both while being hauled up and while taking readings, they may cool the water or warm it - sunlight will heat the water in the bucket quickly - the thermometer will begin at air temperature, and inserting it into the bucket will in fact either heat or cool the water slightly - depending on how hot or cold the thermometer was before insertion in the bucket the water may have cooled or heated a few degrees from the sea temperature before the thermometer gives an accurate reading (before it has matched the water temperature). And that's just off the top of my head. When you're talking about net differences of 1 degree or less Celsius all these little things can give a false reading. The document I refrenced earlier showing anomalies in temperature data showed that ocean temperature readings in the 19th century were the most uncertain precisely because of these factors.
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Post by Apollo Gnomon on Jul 25, 2008 2:14:15 GMT -4
First of all, the observations of arctic sea ice 200 years ago can't really be considered accurate. Crap like this is why I don't read here more than about quarterly anymore. What about observations of sea ice by the sailors trying to get from the Atlantic to the Pacific? There was at least one expedition that got iced in and had to overwinter on or near their ships, waiting for the ice to thaw. I read a book on this sometime in the last year, not remembering the specifics as I type this. I think it took 3 years for one expedition to make it to the Pacific. There is currently an international territorial dispute over the arctic, now that the ice is receding to a degree that makes commercial navigation an economically viable prospect. Link, please, I don't know about this one. I like to think there is a difference between random drunken sailors and scientists. Perhaps I'm an optimist. Can you provide me with any data on this collection method, or are you just speculating? Thermometry is a more mature science than you might think. Bimetallic strip thermometers have been in existence since the -um- mid 1800's. Mercury thermometers are accurate and reliable. They were invented WAY back in the early 1700's What's the data set size for the "bucket" collected samples? Generally speaking, the larger the data set, the less significant individual measurement mistakes become. Given a sufficiently large data set, the mean of all the errors should approximate the most accurate sample. I've noticed that people who "disbelieve" in global warming rely on the same tried and true (or is that tired and trite) techniques that the Hoax Believers use -- slamming down anomalous little factoids on the table and saying "Yeah, well what about THIS?" instead of engaging the data. Is the earth warming at this time? Could the mechanisms of the anthropogenic global warming theory produce the effect of warming earth's atmosphere and oceans? Is the current (if extant) warming trend explainable by any other theory? I can find many different effects, worldwide, suggesting that the earth is currently in a warming trend. I can run the numbers myself and verify that increased CO2 partial pressure increases the infrared absorption by the atmosphere, and that the CO2 then re-radiates that heat at frequencies that do not leave the atmosphere (greenhouse effect). Feedback loops create non-linear effects, and in this case we get increased heat melting polar ice, so the earth is reflecting less heat back into space. So, where's your beef? I don't get it. I've noticed a high degree of overlap between people who believe in Creation and people who disbelieve in global warming. I've also noticed that a large percentage of those in both groups do not actually understand logarithmic numbers, and thus do not fully comprehend how massive time is, and how cosmically small Earth, and by extension humans really are. Just an observation. {edit to correct sentence fragments}
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Jason
Pluto
May all your hits be crits
Posts: 5,579
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Post by Jason on Jul 25, 2008 11:34:52 GMT -4
What about observations of sea ice by the sailors trying to get from the Atlantic to the Pacific? Anecdotal. Conditions in the particular part of the Atlantic where they were might have been bad indeed without indicating that the entire Arctic ocean had thicker ice coverage. Links on antarctic ice expansion: This.This USA Today story. And this BBC News story, which generally supports global warming but also notes how difficult it is to get accurate temperature measurements over Antarctica and accurate measurements of ice in the Arctic, even with satellites. Sure. This document I mentioned earlier in the thread is all about problems and anomalies in compiling a particular set of global temperature data. The wooden bucket sample method is mentioned on pg. 13 of the .pdf. There are several graphs showing how the data is not especially accurate until 1950 or so - see page 21 in particular. This page can give you some of the datasets used in compositing the HadCRUT3 dataset. If the basic data collection method is flawed then a larger sample size can provide some increase in accuracy, but when the net change we're interested in is so small, having a large sample size might not be enough to provide accuracy with a flawed collection method. It's the nature of the debate. The Earth's climate is a very complex system, accurate measurements of temperature only go back around 150 years at the most, and the net change in data points over time is rather small. Questions about accuracy are therefore rational. As I said earlier, I'm not sure if it is. Maybe it is, maybe it isn't. In theory yes. But are they? That is the $25,000 question, isn't it? You can verify that this happens in lab conditions, or by theory. Can you verify that it authentically occur rs on a global scale? Can you eliminate all other factors that might be causing an observed warming trend? My opinion is that we aren't at that point yet. My main beef is that global warming believers are agitating for hugely expensive programs and limits on industry in order to fight a problem that might not even be there, or that might not be caused by human activity (in which case limiting carbon emissions from human sources will have little to no benefit). I fully support rational measures to improve the environment and switch to more efficient, cleaner technologies, but they have to be rational. They have to show definite cost/benefit gains over other areas we might want to spend our time and resources. I think my religious beliefs have very little to do with whether or not I believe in human-caused global warming. Which begs the question of why you think puny human activity over such a small period of time (the Industrial Revolution occurred only around 200 years ago, after all) has been able to have such a profound effect on a system as massive as the Earth's climate.
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Post by Apollo Gnomon on Jul 25, 2008 15:24:41 GMT -4
Q: What about observations of sea ice by the sailors trying to get from the Atlantic to the Pacific? A: Anecdotal.
Well, alrighty then. I guess I'm done banging my head on THIS wall. Nothing else I have to say will be worth the effort, if you can dismiss facts you don't like this easily.
Just like the HBs , innit? Guess I'll check back in next quarter.
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Jason
Pluto
May all your hits be crits
Posts: 5,579
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Post by Jason on Jul 25, 2008 15:38:44 GMT -4
Q: What about observations of sea ice by the sailors trying to get from the Atlantic to the Pacific? A: Anecdotal. Well you don't expect us to accept everything sailors report as fact, do you? No, it's emphatically not just like a dialoge with hoax believers. We're not discussing one of the most remarkable and extensively documented historical events on record here - we're discussing a possible predicted future catastrophe and its alleged causes. If you can't see the difference between the two then you aren't looking very hard.
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Post by Ginnie on Jul 27, 2008 14:36:10 GMT -4
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Post by Apollo Gnomon on Jul 27, 2008 18:40:14 GMT -4
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Jason
Pluto
May all your hits be crits
Posts: 5,579
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Post by Jason on Jul 28, 2008 17:44:33 GMT -4
Here's a story saying that there is more ice than expected in the Arctic Ocean this year.
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Post by dmundt on Jul 29, 2008 18:22:37 GMT -4
I caught a cool draft coming in the living room window today. This is quite unusual for July. Global warming must not be happening.
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