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| Latecommer |
The Glacial Record and its RamificationsIn several papers that I have read in the past weeks,( Petit et al, Kininmonth, Archibald) I have observed that it appears to be accepted that the Milankovitch cycle of 100,000 yrs discribes, at its coolest point, a period of time when dust accumulation indicated a drying period.That is the 'science' of the matter, and I now stray to the anecdotal record of history and ask; What caused the "dust bowl" event of the 1930's when the temperatures were at the highest of the last century. As I understand history, the drought conditions accompaning the hot climate lasted 8 to 10 years and caused the migration of many people from of the lower midwest toward both coasts. Was this just an exception to the general cool/dry conditions that have marked the major dust deposits in the ice core records? |
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| scpg02 |
I thought the dust bowl had more to do with bad agricultural practices as anything else. | ||||
| Latecommer |
I imagine that was a part of it, but the extent of the problem (Minnesota to Texas) indicates at least a fluxuation in climate....to the point of an extended drought, Which occured at what was a warmer decade, According to theory, as I understand it, The 30's should have been one of higher humidity and rainfall.
Just curious about it never being mentioned in any of the papers I have read. |
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| hypatia |
One of my family members, recalls the winds from those years being very strong, stronger then normal. Very high temps too, with weeks of 100 F degree weather. | ||||
| Andre |
Re: The Glacial Record and its Ramifications
Happen to notice the little conflict: cool-arid in the ice ages versus warm-arid during the dust bowl? There will be a lot more about that. |
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| Latecommer |
Andre,
Can I assume that you, in main, agree with Jaworowski and his paper "CO2: the Greatest Scientific Scandal Of Our Time"? Do you agree in specific that the Ice Core data IPCC so depends on to reconstruct past CO2 concentrations and relative isotopic measurements, is fatally flawed? Assuming a yes to the above, can you point to the deciding factors toward this POV? Thanks, Doug |
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| scpg02 |
CO2: The Greatest Scientific
Scandal of Our Time by Zbigniew Jaworowski, M.D., Ph.D., D.Sc. |
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| Andre |
I've seen it, are you in yahoo CS group Maggie?
I have hesitated to post it here, for several reasons. I find it too offensive. If I was to be a genuine honest warmer, I'm sure that I was too shocked by the attacks to contemplate anything of the actual information. I would have sticked to exposing the problems between ice cores and other CO2 proxies/measurements. As HPD has suggested, this news should have been brought cautiously, expressing all kind of doubts. For instance, about the important role of the paper of Ernst-Georg Beck. His digging up all the chemical measurements publications CO2 and assessing them, is very valuable. But you cannot state with confidence that a certain CO2 spike (page 45, fig 3) at a certain point, even for the duration of weeks, resembles the global average. The error that I found, Doug, was in:
The difference between gas age and ice age in ice cores is a well studied feature. As the top layers of the snow are open, the air passes through freely and renews itself constantly. At a depth of about 80-90 meters down, the pressure gets so high that the snow compresses to solid ice with the air bubbles now isolated. Therefore it's the accumulation rate of snow that determines the age difference between air and the ice around it. Fast accumulating ice sheets take dozens of years. The inland of Antarctica is desert though with very little accumulation. The biggest difference there, between gas age and ice age is somewhere at 5-6000 years, not several ten thousands. The "ten" is exagarated. And as I have stated before, if you attack establisment, be sure that your work is flawless, because it will be scrutinized by hundreds/thousands of main streamers and one tiny error and the paper is flawed. Furthermore Jaworowski does not even use all the evidence available, in the stomata research for instance. Leaf stomata from some plants are sensitive for the CO2 concentration. The more CO2, the less stomata. So if you recover fossil plant remains with known stomata behavior, you can reconstruct the CO2 mixing ratios. He uses several examples but he had overlooked McElwain et al 2002 who reconstruct three different proxies with four different plant species all during the Younger Dryas, to get this result fro reconstructing CO2: Also he had overlooked Chap V of the PhD thesis of Lenny Kouwenberg here. Look at pag 7, fig 5.4. See the 400 ppmv CO2 spike around 500AD? Of course the author tries to unexplain it but that's speculation. What is required is duplication. And the stomata generated CO2 levels during the Younger Dryas have been duplicated at several places in the world. it is compiled by Rundgren and Björck 2003, who show this figure: 
which is consistent with several other recontructions like McElwain et al 2002. The early Younger Dryas dip is not visible in the Antarctic ice cores. Reference: Mats Rundgren and Svante Björck 2003 How variable were atmospheric CO2 levels during the last deglaciation? Evidence from stomatal index measurements of a Swedish high-resolution leaf record, XVI INQUA Congress July 23-30, 2003 Reno, Nevada, USA Abstract no. 53595 J.C. McElwain, F.E. Mayle And D.J. Beerling, 2002, Stomatal evidence for a decline in atmospheric CO2 concentration during the Younger Dryas stadial: a comparison with Antarctic ice core records. Journal Of Quaternary Science (2002) 17(1) 21–29 |
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| scpg02 |
Nope. |
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| Andre |
Climate sceptics is a very active members only Yahoo discussion group. In the old days it was strictly reserved for scientists and journalists. Nowadays, I believe the current moderator David Wojick has loosened up a bit. If you tell him that you know me(climatesceptics-subscribe@yahoogroups.com), he may let you in. But beware if you subscribe to receiving all mails. I have counted over 50 in one day. Also recommending CCNet of Benny Peiser. |
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| Latecommer |
Thank you Andre,
I found his style offensive as well, but enjoyed the substance of his paper. I agree that a few tentative first steps to raise interest in the idea would have been prudent. thank you for your explaination Doug |
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