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Post by thehawg on Apr 11, 2009 19:30:10 GMT
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Post by socold on Apr 13, 2009 21:02:44 GMT
One obvious flaw is that they admit temperature have risen in the last few decades (citing the satellite records - or rather just one of them), but the divergance still exists in this time period. Ie the tree proxies should have shown this warming, but as per the divergance they don't.
It's not correct that the divergance problem doesn't exist for the satellite records. The satellite records show the same amount of warming as the surface records since 1979.
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Post by magellan on Apr 14, 2009 1:32:41 GMT
One obvious flaw is that they admit temperature have risen in the last few decades (citing the satellite records - or rather just one of them), but the divergance still exists in this time period. Ie the tree proxies should have shown this warming, but as per the divergance they don't. It's not correct that the divergance problem doesn't exist for the satellite records. The satellite records show the same amount of warming as the surface records since 1979. The satellite records show the same amount of warming as the surface records since 1979 Um, no they don't.
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Post by poitsplace on Apr 14, 2009 4:50:01 GMT
One obvious flaw is that they admit temperature have risen in the last few decades (citing the satellite records - or rather just one of them), but the divergance still exists in this time period. Ie the tree proxies should have shown this warming, but as per the divergance they don't. It's not correct that the divergance problem doesn't exist for the satellite records. The satellite records show the same amount of warming as the surface records since 1979. At issue is the notion that the climate has remained constant. How far off are the proxies? The various proxies are all over the place for global temperature. However, the ones convenient to the current AGW dogma are accepted as fact even though they've been absolutely shredded by peer review. AGW proponents would rather believe the earth's climate is somehow static during the interglacial periods and that there are only localized regions showing warming/cooling. We have direct evidence that certain wind and ocean current configurations cause GLOBAL warming and cooling. AGW proponents of course say a very similar thing is responsible for the LIA/MWP but that THOSE conditions didn't warm or cool the whole planet. It's just like the recent lack of volcanic actiivty and the (until recently) high solar activity that isn't counted by alarmists...until things don't go their way. Then suddenly the renewed threat of volcanic activity and a solar minimum can be responsible again...but only for cooling.
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Post by socold on Apr 16, 2009 0:38:31 GMT
One obvious flaw is that they admit temperature have risen in the last few decades (citing the satellite records - or rather just one of them), but the divergance still exists in this time period. Ie the tree proxies should have shown this warming, but as per the divergance they don't. It's not correct that the divergance problem doesn't exist for the satellite records. The satellite records show the same amount of warming as the surface records since 1979. The satellite records show the same amount of warming as the surface records since 1979 Um, no they don't. Yep all between 0.13C and 0.15C warming per decade. UAH is deviates the most at the low end. There is nothing much of a disagreement there.
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Post by socold on Apr 16, 2009 0:42:10 GMT
One obvious flaw is that they admit temperature have risen in the last few decades (citing the satellite records - or rather just one of them), but the divergance still exists in this time period. Ie the tree proxies should have shown this warming, but as per the divergance they don't. It's not correct that the divergance problem doesn't exist for the satellite records. The satellite records show the same amount of warming as the surface records since 1979. At issue is the notion that the climate has remained constant. I disagree. The issue in question is the divergance problem. As per my point about the satellite records which diverge from the proxies too.
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Post by poitsplace on Apr 16, 2009 4:08:09 GMT
At issue is the notion that the climate has remained constant. I disagree. The issue in question is the divergance problem. As per my point about the satellite records which diverge from the proxies too. So there was no medieval warm period or little ice age because the proxies say so...but it doesn't phase you one bit when the proxies suffer epic failure on the current warming. You simply explain away the little ice age and medieval warm period as a localized phenomenon based on persistent ocean/wind currents...which (from all observed data we have TODAY) affect temperatures globally. All this stability in the global temperatures for thousands of years..in a world dominated by incredibly strong positive feedbacks. Do you know how stupid that sounds? The Earth warms, the Earth cools and we're just not sure why. It's been doing it this whole time. The idea of substantial anthropogenic global warming from CO2 is based on revisionist history, ignoring important aspects of the physics and assumptions of behavior of processes that even the experts admit...we have little understanding of.
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Post by tacoman25 on Apr 16, 2009 6:05:58 GMT
The satellite records show the same amount of warming as the surface records since 1979 Um, no they don't. Yep all between 0.13C and 0.15C warming per decade. UAH is deviates the most at the low end. There is nothing much of a disagreement there. However, in recent years GISS has easily had the largest divergence, showing 2005 and 2007 to be much warmer than the other sources.
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Post by glc on Apr 16, 2009 7:46:52 GMT
However, in recent years GISS has easily had the largest divergence, showing 2005 and 2007 to be much warmer than the other sources. Probably because they try to estimate the Arctic - and there's good reason to believe that they have done a reasonable job. The arctic ice melt in 2007 , for whatever reason, suggests an anomalously warm arctic region. More recently, the arctic has been less warm and GISS anomalies have been lower. Using the same base period as the satellites (1979-1997), GISS anomalies have been lower than UAH in Jan, Feb and March this year. Jan: GISS +0.25 ; UAH +0.30 Feb: GISS +0.15 ; UAH +0.36 Mar: GISS +0.18 ; UAH +0.21
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Post by gettingchilly on Apr 16, 2009 22:52:22 GMT
Lets not forget that the only time you would ever use a proxy is if the real data is missing so it's a best guess reconstruction. If your bank sent you a "proxy" bank statement, you would be on the phone straight away wanting the real data. Bottom line is, proxy's are ropey at best but if that's all that you have then give it a go. If you have real data then discard the proxy. Comparisons of real data with proxy data are of no real value whatsoever as real data is what matters. Assuming of course that the "real" data has not been deviously adjusted.
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Post by icefisher on Apr 17, 2009 1:36:12 GMT
Lets not forget that the only time you would ever use a proxy is if the real data is missing so it's a best guess reconstruction. If your bank sent you a "proxy" bank statement, you would be on the phone straight away wanting the real data. Bottom line is, proxy's are ropey at best but if that's all that you have then give it a go. If you have real data then discard the proxy. Comparisons of real data with proxy data are of no real value whatsoever as real data is what matters. Assuming of course that the "real" data has not been deviously adjusted. I agree completely. I wonder if anybody knows of a paper dealing with the "proxy" issue itself.
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Post by thehawg on Apr 17, 2009 2:58:50 GMT
Lets not forget that the only time you would ever use a proxy is if the real data is missing so it's a best guess reconstruction. If your bank sent you a "proxy" bank statement, you would be on the phone straight away wanting the real data. Bottom line is, proxy's are ropey at best but if that's all that you have then give it a go. If you have real data then discard the proxy. Comparisons of real data with proxy data are of no real value whatsoever as real data is what matters. Assuming of course that the "real" data has not been deviously adjusted. That's a quote I can take to the bank. Thanks for that one.
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jtom
Level 3 Rank
Posts: 248
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Post by jtom on Apr 17, 2009 4:07:20 GMT
"Comparisons of real data with proxy data are of no real value whatsoever as real data is what matters."
I have to take issue with that. One determines the validity of a proxy by comparing it to real data. If it appears to correlate, it can be hypothesized to be a valid proxy. However, if it is ever shown to substantially deviate from real data, the validity of using it as a proxy for those periods absent data must be reconsidered.
If a proxy can be shown to be invalid based on data today, then it can not be used as a proxy for earlier events.
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Post by tacoman25 on Apr 17, 2009 6:18:41 GMT
However, in recent years GISS has easily had the largest divergence, showing 2005 and 2007 to be much warmer than the other sources. Probably because they try to estimate the Arctic - and there's good reason to believe that they have done a reasonable job. The arctic ice melt in 2007 , for whatever reason, suggests an anomalously warm arctic region. More recently, the arctic has been less warm and GISS anomalies have been lower. Using the same base period as the satellites (1979-1997), GISS anomalies have been lower than UAH in Jan, Feb and March this year. Jan: GISS +0.25 ; UAH +0.30 Feb: GISS +0.15 ; UAH +0.36 Mar: GISS +0.18 ; UAH +0.21 Perhaps. But they have still been closer this year than they were in 2005 or 2007. Especially if you look at the other temperature sources besides UAH.
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Post by jimg on Apr 17, 2009 6:22:53 GMT
Yeah, what jtom said.
I was going to say that but he beat me to it.
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