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Ice Ages & Astronomical Causes Origin of the 100 kyr Glacial Cycle
Figure 1-5 Climate for the last 420 kyr, from Vostok ice |
Posted on 09/27/2003 7:50:35 AM PDT by Forgiven_Sinner
Do abrupt climate shifts occur as part of a natural cycle? Despite growing evidence that humans affect climate via urbanization and greenhouse gas emissions, the natural climate cycle may have the final say.
Research from Dr. Stefan Rahmstorf at Germany`s Potsdam Institute for Climate Impact Research suggests that the earth`s climate is characterized by an extraordinarily regular cycle of about 1470 years.
He found that the five most recent cycles had a standard deviation of only 32 years.
Rahmstorf examined ice cores from Greenland. Going back before the 20th century, when weather stations were nonexistent or widely dispersed, ice cores and tree rings provide the most objective and reliable climate record.
Rahmstorf also found that the most recent cold period of the cycle was most likely the "Little Ice Age" of the 16th to 18th Centuries.
These findings suggest that the warming of the past century or so is probably nothing more than the next phase of this repeating pattern of cyclical warming and cooling.
Recent observations and forecast models suggest that the current warming may be the engine to spur rapid global cooling.
Ocean scientists have found that some of the largest rivers in the world are dumping 7% less fresh water into the Arctic Ocean than they did in the 1930s.
According to scientists at the Woods Hole Oceanographic Institution, decreased fresh water flow has the potential to shut down a global water flow pattern called the thermohaline circulation.
In its current state, the thermohaline circulation brings cold, deep, salty water south from the poles, while warm surface water moves from the tropics toward the poles. If the circulation were to shut off, abrupt cooling would likely spread through much of the northern Hemisphere, including Europe and the U.S.
This scenario has caused temperatures to plummet an average of 5 to 10 degrees in 20 years in the past. 11,000 years ago, such global cooling occurred and glaciers were seen in much of the northern U.S.
Photo Credit: NOAA Photo Library. The Ross Ice Shelf looms over the Bay of Whales. It was here that Roald Amundsen staged the first successful assault on the South Pole.
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When we need the fuel to keep us warm it will be too late.
The fable of the ants and the grasshopper is as relevent today than ever.
50 years from now, half of the people in Canada will begin migrating south.
Those of you young enough might remember my prediction.
We are all going to die at any second!
Keep remembering!
From what I can gather, we are in a short-term warming trend in a cycle that has the earth on the edge of a new Ice Age, which as this author says, could unfold in a 20-year time-frame.
Twenty years! And it could 'start' tomorrow.
Oh wait, none of their dire predictions regarding global warming for the past 15 years have come true? So its back to crying ice age.
It is so hard to keep up which what doom and gloom prediction is in fad.
In another dozen years the 'environmental experts' will be whining about something new --maybe global rounding or some such thing. And if you dare to mention Kyoto they'll stare blankly as they do now when you remind them how they used to accuse Ronald Reagan of plunging us into an ice age.
Finally, an explanation why they already live close to the border.
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Ice Ages & Astronomical Causes Origin of the 100 kyr Glacial Cycle
Figure 1-5 Climate for the last 420 kyr, from Vostok ice |
Mankind's impact is only 0.28% of Total Greenhouse effect
" There is no dispute at all about the fact that even if punctiliously observed, (the Kyoto Protocol) would have an imperceptible effect on future temperatures -- one-twentieth of a degree by 2050. "
Dr. S. Fred Singer, atmospheric physicist
Professor Emeritus of Environmental Sciences at the University of Virginia,
and former director of the US Weather Satellite Service;
in a Sept. 10, 2001 Letter to Editor, Wall Street Journal
Anthropogenic (man-made) Contribution to the "Greenhouse
Effect," expressed as % of Total (water vapor INCLUDED)
Based on concentrations (ppb) adjusted for heat retention characteristics % of All Greenhouse Gases % Natural
% Man-made
Water vapor 95.000% 94.999%
0.001% Carbon Dioxide (CO2) 3.618% 3.502%
0.117% Methane (CH4) 0.360% 0.294%
0.066% Nitrous Oxide (N2O) 0.950% 0.903%
0.047% Misc. gases ( CFC's, etc.) 0.072% 0.025%
0.047% Total 100.00% 99.72
0.28%
The reality is a doubling of atmospheric CO2 concentration over current levels, that the IPCC "story line" pretends, even if were true, could not induce significant temperature change whatever its source.
Climate Catastrophe, A spectroscopic Artifact?
"It is hardly to be expected that for CO2 doubling an increment of IR absorption at the 15 µm edges by 0.17% can cause any significant global warming or even a climate catastrophe.
The radiative forcing for doubling can be calculated by using this figure. If we allocate an absorption of 32 W/m2 [14] over 180º steradiant to the total integral (area) of the n3 band as observed from satellite measurements (Hanel et al., 1971) and applied to a standard atmosphere, and take an increment of 0.17%, the absorption is 0.054 W/m2 - and not 4.3 W/m2.
This is roughly 80 times less than IPCC's radiative forcing.
If we allocate 7.2 degC as greenhouse effect for the present CO2 (as asserted by Kondratjew and Moskalenko in J.T. Houghton's book The Global Climate [14]), the doubling effect should be 0.17% which is 0.012 degC only. If we take 1/80 of the 1.2 degC that result from Stefan-Boltzmann's law with a radiative forcing of 4.3 W/m2, we get a similar value of 0.015 degC."
A Lukewarm Greenhouse
"The average warming predicted by the six methods for a doubling of CO2, is only +0.2 degC."
I love how these throw-away lines are slipped into these articles...as if this "evidence" is unquestionable.
But scientists have found evidence of tropical climates at the poles. When do we get that part of the cycle?
The antarctic has not always been where it is located today, at one time that landmass was much closer to the equator, it moves due to continental drift to the southern pole, hence no tropical climate for that land mass anymore.
If you want to guess on a world wide heat up with no or little polar ice, figure on at least a few million years to get through the current series of ice ages.
We have got anywhere from 10 to 50 million years before another real heatup to global tropical temps if ever.
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Global Temperature and Atmospheric CO2 over Geologic Time
Late Carboniferous to Early Permian time (315 mya -- 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ). Temperature after C.R. Scotese
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