nikmb
New Member
Posts: 10
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Post by nikmb on Sept 4, 2009 6:51:18 GMT
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Post by poitsplace on Sept 4, 2009 9:04:36 GMT
What's this...the bulk of the warming came by the 30's and 40's when man's contribution was minimal. I tell you, CO2 sure is crazy stuff. It's "almost" as if CO2 has f*ck-all to do with climate. It's a good thing we just "know" it's the cause...otherwise we'd be forced by the actual evidence to just assume it was some kind of crazy ol' natural variation that we just didn't fully understand.
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Post by neilhamp on Sept 4, 2009 9:31:19 GMT
Darrell Kaufman claims "The 20th Century stands out in strong contrast to the cooling that should have continued. The last half-century was the warmest of the 2,000-year temperature record, and the last 10 years have been especially dramatic," he told BBC News." Checking out www.climate4you.com/ (Polar temperatures) The "warming in the last 10 years" (1.5 degrees) is far less rapid than that experienced in the 1920's (3.5 degrees). I have not yet heard anyone explain the dramatic 1920's warming.
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Post by glc on Sept 4, 2009 9:33:39 GMT
Before posters start dismissing this study as fraudulent or whatever, can we just think about it for a bit. Let's accept the findings at face value and consider what they might mean. The ice core reconstruction does look like Mann's H-S, though. / UPDATE: Well done, poitsplace, you have given it some thought. you must have posted just as I was writing this. A good start. The only thing (regarding your comment) is that the AGWers will claim that aerosols dampened the late 20 th century warming. But you're right that ~30 ppm seems to be responsible for ~1 deg warming while the next 70 ppm has done nothing much at all.
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Post by poitsplace on Sept 4, 2009 10:56:14 GMT
UPDATE: Well done, poitsplace, you have given it some thought. you must have posted just as I was writing this. A good start. The only thing (regarding your comment) is that the AGWers will claim that aerosols dampened the late 20th century warming Or they might not www.nasa.gov/topics/earth/features/warming_aerosols.html
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Post by glc on Sept 4, 2009 12:47:07 GMT
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Post by radiant on Sept 4, 2009 14:25:12 GMT
I suspect the study authors have used models to arrive at the conclusion that such a hockey stick graph exists. Either way since we have no idea how they were able to determine the temperatures 1000 years ago so that they could refute the work done by other authors that temperatures were higher 1000 years ago the sensible thing to do is to wait until we can examine the study and then disect it for observer bias and errors. This is called peer review or something like it and is essential to any scientific study to ensure that wish fullfillment does not occur due to the desire of the authors to increase their credibility with their own group who all tend to believe the same things. Fundamentally science is a flawed process involving human egos and frailities that evolves as ideas come and go and our understanding increases - a process that can often take generations to mature. Meanwhile if all of their temperatures were arrived at using a single method with no modelling i would be quite impressed. Edit: Here we go. They 'reconstructed' their own data and the data of others who confirmed their bias and used a computer model to simulate climate change over the last 2000 years. www.cbc.ca/technology/story/2009/09/03/climate-environment-arctic-change.htmlThe study, published this week in Science, was based on previously published data by Kaufman's team from studies of sediment cores taken from 14 lakes. It also included a computer simulation of climate change over the last 2,000 years, which agrees with the climate model proposed by the National Center for Atmospheric Research used to predict future climate change
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Post by nancyw on Sept 4, 2009 16:06:02 GMT
Excellent. Plus of course, the arctic doesn't receive sunlight for half the year, so the reflective properties of aerosols woud be irrelevant for much of the time. I'm not sure I understand this statement.......I'm not sure that anyplace on earth receives sunlight for more than half the year(day/night). Isn't that also true of the arctic region, except that the daylight hours are distributed more seasonally?
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Post by radiant on Sept 4, 2009 16:25:57 GMT
Excellent. Plus of course, the arctic doesn't receive sunlight for half the year, so the reflective properties of aerosols woud be irrelevant for much of the time. I'm not sure I understand this statement.......I'm not sure that anyplace on earth receives sunlight for more than half the year(day/night). Isn't that also true of the arctic region, except that the daylight hours are distributed more seasonally? I propose that because most of the arctic is at sea level it does not get as much daylight as the pointy bits in greenland where there is a massive pile of ice. As proof of this theory i offer this recent photo of the North slope of Alaska photographed the other day by one of the north west passagers
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Post by jeroen on Sept 4, 2009 17:46:57 GMT
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Post by byz on Sept 4, 2009 19:23:41 GMT
But you're right that ~30 ppm seems to be responsible for ~1 deg warming while the next 70 ppm has done nothing much at all. glc as we have discussed before CO2 to warming has a logarithmic relationship to warming so that would be expected! A little CO2 makes a BIG increase in temperature whereas a lot of CO2 after the initial amount make very little difference So going from 10 ppm to 20 ppm has a bigger effect than 300 ppm to 600 ppm ;D PS you never explained where the constant from the equation you supplied was from (as the constant had a bigger effect than the CO2) ;D
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Post by woodstove on Sept 4, 2009 19:49:34 GMT
I'd like to see some of these "hockey-stickers" actually play a little pond hockey. Or even go outside.
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Post by glc on Sept 4, 2009 20:28:42 GMT
Excellent. Plus of course, the arctic doesn't receive sunlight for half the year, so the reflective properties of aerosols woud be irrelevant for much of the time. I'm not sure I understand this statement.......I'm not sure that anyplace on earth receives sunlight for more than half the year(day/night). Isn't that also true of the arctic region, except that the daylight hours are distributed more seasonally? So there should be a signal in the seasonal trends.
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Post by glc on Sept 4, 2009 20:50:18 GMT
glc as we have discussed before CO2 to warming has a logarithmic relationship to warming so that would be expected!
Yes I know.
A little CO2 makes a BIG increase in temperature whereas a lot of CO2 after the initial amount make very little difference
That's not quite how it works.
So going from 10 ppm to 20 ppm has a bigger effect than 300 ppm to 600 ppm
Yes - but going from 315 ppm to 385 ppm should result in a bigger increase in temperature than 285 ppm to 315 ppm. In fact it should be about twice as much warming as it happens
ln(385/315) = ~2 x ln(315/285) PS you never explained where the constant from the equation you supplied was from (as the constant had a bigger effect than the CO2)
I take it you mean the alpha (5.35) constant in the Myhre et al formula. Basically (very) it's derived by calculating CO2 forcings using radiative transfer equations and using regression to fit the log function. At least I think that's what was done but I haven't read the paper so there is an element of gueswork here, but the most likely procedure would be as I've described.
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Post by magellan on Sept 5, 2009 2:22:30 GMT
Kaufman and Upside-Down Mann www.climateaudit.org/?p=6932#commentsRead carefully. Folks, this is just more of the same crap-through-a-goose "peer reviewed" fraud research in the now tabloid journal Science.
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