Posted on 10/28/2006 11:42:19 PM PDT by Dallas59
The rise of the Appalachian Mountains seems to have triggered an ice age 450 million years ago by sucking CO2 from the atmosphere. Researchers report evidence that minerals from the mountain range washed into the oceans just before the cold snap, carrying atmospheric carbon dioxide with them. The result clarifies a long standing paradox in the historical relationship between CO2 and climate, experts say.
At the start of the so-called Ordovician ice age, about 450 million years ago, the planet went from a state of greenhouse warmth to one of glacial cold, culminating in mass extinctions of ocean life. This period has always posed a problem for climate modelers, notes geologist Matthew Saltzman of Ohio State University. "The models for CO2 that span that interval have always shown levels that are much too high to have an ice age," he explains. "That was a real paradox." Researchers believe that the last ice age, which began 40 million years ago, was kicked off by the rise of the Himalayas during the collision of tectonic plates and a corresponding plunge in atmospheric carbon dioxide. Ocean deposits of calcium carbonate, or limestone, indicate that CO2-rich rainwater stripped calcium and strontium from the Himalayan rock; these elements fused with the carbon dioxide and spilled into the sea, effectively pulling carbon from the atmosphere.
The same chemical weathering commenced before the Ordovician ice age, Saltzman and his student Seth Young reported today at a meeting of the Geological Society of America. The pair analyzed the ratio of strontium isotopes in rocks from Nevada and Europe that date to the Ordovician climate reversal. Right before the ice age begins the ratio becomes low in strontium 87, which accumulates as rock ages, suggesting weathering of relatively young rock. And indeed at that time the Appalachians would have been forming from a Japan-like arc of islands smashing onto what is now North America. "We have pretty good evidence that in fact there was a weathering event that had to involve a significant removal of carbon dioxide," Saltzman says. "If you include the strontium data [in CO2 models] then you can very easily force the drop in CO2 that hadn't been there."
The result helps clear up a "particularly enigmatic" ice age, says geoscientist Lee Kump of Pennsylvania State University. "Solving the enigma is an important step forward" in building confidence in the relationship between CO2 and climate change, he says. --
I was thinking the opposite. That the article implies that strip mining (or possibly deforestation) would expose more new rock that would fuse with co2 and wash into the sea thus lowering the co2 level in the atmosphere. But what do I know? Perhaps the guy in a previous reply who suggested we remove the Appalachians has the right idea?
I am sincerely interested in the hard Science of Climate models and both the historical study of our atmosphere and yes, the CO2 modeling. Of greatest interest to me personally is the far and wide ranging predictions and forecasts that have been quoted in the media and indeed, generated by many, many different computer driven models.
Now, according to my sources, temps have risen within a normal range, and we have nothing to fear from rises in CO2, since our planet has been designed to balance out or self-adjust, IMO.
http://www.cato.org/pubs/regulation/reg15n2g.html
Richard S. Lindzen
Summary of Scientific Issues:
Before even considering "greenhouse theory,'' it may be helpful to begin with the issue that is almost always taken as a given--that carbon dioxide will inevitably increase to values double and even quadruple present values. Evidence from the analysis of ice cores and after 1958 from direct atmospheric sampling shows that the amount of carbon dioxide in the air has been increasing since 1800. Before 1800 the density was about 275 parts per million by volume. Today it is about 355 parts per million by volume. The increase is generally believed to be due to the combination of increased burning of fossil fuels and before 1905 to deforestation. The total source is estimated to have been increasing exponentially at least until 1973. From 1973 until 1990 the rate of increase has been much slower, however. About half the production of carbon dioxide has appeared in the atmosphere.
Predicting what will happen to carbon dioxide over the next century is a rather uncertain matter. By assuming a shift toward the increased use of coal, rapid advances in the third world's standard of living, large population increases, and a reduction in nuclear and other non-fossil fuels, one can generate an emissions scenario that will lead to a doubling of carbon dioxide by 2030--if one uses a particular model for the chemical response to carbon dioxide emissions. The Intergovernmental Panel on Climate Change Working Group I's model referred to that as the "business as usual'' scenario. As it turns out, the chemical model used was inconsistent with the past century's record; it would have predicted that we would already have about 400 parts per million by volume. An improved model developed at the Max Planck Institute in Hamburg shows that even the "business as usual'' scenario does not double carbon dioxide by the year 2100. It seems unlikely moreover that the indefinite future of energy belongs to coal. I also find it difficult to believe that technology will not lead to improved nuclear reactors within fifty years.
Nevertheless, we have already seen a significant increase in carbon dioxide that has been accompanied by increases in other minor greenhouse gases such as methane and chlorofluorocarbons. Indeed, in terms of greenhouse potential, we have had the equivalent of a 50 percent increase in carbon dioxide over the past century. The effects of those increases are certainly worth studying--quite independent of any uncertain future scenarios.
Please carefully consider further study of the:
Max Planck Institute for Meteorology (MPI-M), Hamburg, Germany
Global climate modeling
Scientists:
Group leader: Erich Roeckner (A Lefty Green Party fan - no doubt)
Staff members:
Manik Bali, Jan Baudisch, Luca Bonaventura, Renate Brokopf, Traute Crueger, Monika Esch, Reiner Schnur, Jana Sillmann, Min Wei
General aim
The overall mission is to contribute to the understanding of climate variability from inter-annual to centennial time scales. This comprises the response of the Earth System to both natural and anthropogenic forcing, the role of feedbacks with particular emphasis on the interactions between the physical climate system and the carbon cycle, and the detection and attribution (D&A) of anthropogenic climate change.
http://www.mpimet.mpg.de/en/wissens...dellierung.html
Why don't we discuss why the last ice age ended, and round about 10,000 to 8,000 years ago?
Why did temps rise on average 6 - 7 C
Next, if the last ice age peaked around 15,000 years ago, could this be studied in relation to Co2 levels or in the perspective of other factors?
Dang, nice panorama! Did you take that photo?
With my Olympus and a program by the name of "The Panorama Factory".
Thank you for that information.
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Links or a book reference, please?
Cheers!
Here you go:
Enjoy!
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