Beam me to Planet Gore !
Posted on 05/19/2008 2:32:40 PM PDT by cogitator
The newest analysis of trace gases trapped in Antarctic ice cores now provide a reasonable view of greenhouse gas concentrations as much as 800,000 years into the past, and are further confirming the link between greenhouse gas levels and global warming, scientists reported in the journal Nature.
They also show that during that entire period of time, there have never been concentrations of carbon dioxide and methane as high as the current levels, said Edward Brook, an associate professor of geosciences at Oregon State University, and author of a Nature commentary on the new studies.
"The fundamental conclusion that today's concentrations of these greenhouse gases have no past analogue in the ice-core record remains firm," Brook said in the report. "The remarkably strong correlations of methane and carbon dioxide with temperature reconstructions also stand."
The latest research, done by members of the European Project for Ice Coring in Antarctica, extend the data on trace gases back another 150,000 years beyond any studies done prior to this, Brook said. Ultimately, researchers would like to achieve data going back as much as 1.5 million years.
The tiny bubbles of ancient air trapped in polar ice cores have been used to provide records of trace gases in the atmosphere at distant points in the past, and better understand the natural fluctuations that have occurred, largely as a result of cyclical changes in Earth's orbit around the sun.
"These natural cycles that occur on the order of tens or hundreds of thousands of years can help us understand both the forces that have controlled and influenced Earth's climate in the past, and the implications of current changes on future climate" said Brook, who is co-chair of an international group that organizes global studies in this field.
According to the data, the current levels of primary greenhouse gases - those that are expected to cause global warming - are off the charts.
The concentration of carbon dioxide is now a bit more than 380 parts per million, compared to a range of about 200-300 parts per million during the past 800,000 years. The current concentration of methane is 1,800 parts per billion, compared to a range of about 400-700 parts per billion during that time.
In every case during that extended period, warm periods coincide with high levels of greenhouse gases. Of some interest, the latest studies are showing that the temperature increases have been even more pronounced during the most recent 450,000 years, compared to several hundred thousand years prior to that.
"It appears there may even be very long term natural cycles that have operated on much longer periods of 400,000 years or more," Brook said. "We still have quite a bit to learn about these past cycles and all the forces that control them."
Most of the time during the past 800,000 years, the Earth has experienced long, cooler periods about 80,000 to 90,000 years long, which eventually lead to ice ages.
Those have been regularly interrupted by "interglacial" periods about 10,000 to 20,000 years long that are considerably warmer - this is the stage the Earth is in right now. Abrupt climate changes on much shorter time scales are also possible, researchers believe, possibly due to shifts in ocean circulation patterns or other forces.
Scientists are continuing to search for the optimal sites in Antarctica that will allow them to take the ice core records back even further, Brook said.
Stop plate tectonics immediately.
Does Al Gore know about this? Seriously folks, if there are so many natural forces at work that are part of the alleged problem, why is Al Gore beating us over the head about our carbon footprints? And our carbon footprints may be a drop in the bucket compared to the natural forces at work.
ABSTRACT:
"Carbon dioxide in the atmosphere is the product of oceanic respiration due to the well-known but under-appreciated solubility pump. Carbon dioxide rises out of warm ocean waters where it is added to the atmosphere. There it is mixed with residual and accidental CO2, and circulated, to be absorbed into the sink of the cold ocean waters. Next the thermohaline circulation carries the CO2-rich sea water deep into the ocean. A millennium later it appears at the surface in warm waters, saturated by lower pressure and higher temperature, to be exhausted back into the atmosphere. Throughout the past 420 millennia, comprising four interglacial periods, the Vostok record of atmospheric carbon dioxide concentration is imprinted with, and fully characterized by, the physics of the solubility of CO2 in water, along with the lag in the deep ocean circulation. Notwithstanding that carbon dioxide is a greenhouse gas, atmospheric carbon dioxide has neither caused nor amplified global temperature increases. Increased carbon dioxide has been an effect of global warming, not a cause. Technically, carbon dioxide is a lagging proxy for ocean temperatures. When global temperature, and along with it, ocean temperature rises, the physics of solubility causes atmospheric CO2 to increase. If increases in carbon dioxide, or any other greenhouse gas, could have in turn raised global temperatures, the positive feedback would have been catastrophic. While the conditions for such a catastrophe were present in the Vostok record from natural causes, the runaway event did not occur. Carbon dioxide does not accumulate in the atmosphere."
http://www.rocketscientistsjournal.com/2006/10/co2_acquittal.html
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The graph above represents temperature and CO2 levels over the past 400,000 years. It is the same exact data Al Gore and the rest of the man-made global warmers refer to. The blue line is temps, the red CO2 levels. The deep valleys represent 4 separate glaciation periods. Now look very carefully at this relationship between temps and CO2 levels and keep in mind that Gore claims this data is the 'proof' that CO2 has warmed the earth in the past. But does the graph indeed show this? Nope. In fact, rising CO2 levels all throughout this 400,000 year period actually lagged behind temperature increases --by an average of 800 years! So it couldn't have been CO2 that got Earth out of these 4 past glaciations. Yet Gore dishonestly and continually claims otherwise.-Eye On The Left
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"The above chart shows the range of global temperature through the last 500 million years. There is no statistical correlation between the level of carbon dioxide in the atmosphere through the last 500 million years and the temperature record in this interval. In fact, one of the highest levels of carbon dioxide concentration occurred during a major ice age that occurred about 450 million years ago. Carbon dioxide concentrations at that time were about 15 times higher than at present.":
http://www.tcsdaily.com/article.aspx?id=010405M
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FWD:
So, greenhouse [effect] is all about carbon dioxide, right?
Wrong. The most important players on the greenhouse stage are water vapor and clouds. Carbon dioxide has been increased to about 0.038% of the atmosphere (possibly from about 0.028% pre-Industrial Revolution) while water in its various forms ranges from 0% to 4% of the atmosphere and its properties vary by what form it is in and even at what altitude it is found in the atmosphere.
In simple terms the bulk of Earth's greenhouse effect is due to water vapor by virtue of its abundance. Water accounts for about 90% of the Earth's greenhouse effect -- perhaps 70% is due to water vapor and about 20% due to clouds (mostly water droplets), some estimates put water as high as 95% of Earth's total tropospheric greenhouse effect (e.g., Freidenreich and Ramaswamy, 'Solar Radiation Absorption by Carbon Dioxide, Overlap with Water, and a Parameterization for General Circulation Models,' Journal of Geophysical Research 98 (1993):7255-7264).
The remaining portion comes from carbon dioxide, nitrous oxide, methane, ozone and miscellaneous other 'minor greenhouse gases.' As an example of the relative importance of water it should be noted that changes in the relative humidity on the order of 1.3-4% are equivalent to the effect of doubling CO2.
http://www.junkscience.com/Greenhouse/
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Water Vapor Rules the Greenhouse System
Water vapor constitutes Earth's most significant greenhouse gas, accounting for about 95% of Earth's greenhouse effect (4). Interestingly, many 'facts and figures' regarding global warming completely ignore the powerful effects of water vapor in the greenhouse system, carelessly (perhaps, deliberately) overstating human impacts as much as 20-fold.
Water vapor is 99.999% of natural origin. Other atmospheric greenhouse gases, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and miscellaneous other gases (CFC's, etc.), are also mostly of natural origin (except for the latter, which is mostly anthropogenic).
Human activites contribute slightly to greenhouse gas concentrations through farming, manufacturing, power generation, and transportation. However, these emissions are so dwarfed in comparison to emissions from natural sources we can do nothing about, that even the most costly efforts to limit human emissions would have a very small-- perhaps undetectable-- effect on global climate.
http://www.geocraft.com/WVFossils/greenhouse_data.html
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Correlation does not necessarily imply causality. In fact, it is just as reasonable to conclude that warm periods result in increases in greenhouse gases rather than the other way around.
boink
Of course, the main discussion will be on the glacial/interglacial transition (or just general AGW discussion).
It’s great that the record has been pushed back 150K...any idea on the quality of their work? Any word on comments from other teams?
From BBC News [yr: 2004]:
"A new [2004] analysis shows that the Sun is more active now than it has been at anytime in the previous 1,000 years. Scientists based at the Institute for Astronomy in Zurich used ice cores from Greenland to construct a picture of our star's activity in the past. They say that over the last century the number of sunspots rose at the same time that the Earth's climate became steadily warmer."..."In particular, it has been noted that between about 1645 and 1715, few sunspots were seen on the Sun's surface. This period is called the Maunder Minimum after the English astronomer who studied it. It coincided with a spell of prolonged cold weather often referred to as the "Little Ice Age". Solar scientists strongly suspect there is a link between the two events - but the exact mechanism remains elusive."
http://news.bbc.co.uk/1/hi/sci/tech/3869753.stm
It's really hard to imagine how this little ball of fire could have any impact on our climate at all.
But the main arguments being made for a solar-climate connection is not so much to do with the heat of the Sun but rather with its magnetic cycles. When the Sun is more magnetically active (typically around the peak of the 11 year sunspot cycle --we are a few yrs away at the moment), the Sun's magnetic field is better able to deflect away incoming galactic cosmic rays (highly energetic charged particles coming from outside the solar system). The GCRs are thought to help in the formation of low-level cumulus clouds -the type of clouds that BLOCK sunlight and help cool the Earth. So when the Sun's MF is acting up (not like now), less GCRs reach the Earth's atmosphere, less low level sunlight-blocking clouds form, and more sunlight gets through to warm the Earth's surface...naturally. Clouds are basically made up of tiny water droplets. When minute particles in the atmosphere become ionized by incoming GCRs they become very 'attractive' to water molecules, in a purely chemical sense of the word.-Eye On The Left
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There's a relatively new book out on the subject titled The Chilling Stars. It's written by one of the top scientists advancing the theory (Henrik Svensmark).
And here is the website for the place where he does his research:
2008: "The Center for Sun-Climate Research at the DNSC investigates the connection between variations in the intensity of cosmic rays and climatic changes on Earth. This field of research has been given the name 'cosmoclimatology'"..."Cosmic ray intensities – and therefore cloudiness – keep changing because the Sun's magnetic field varies in its ability to repel cosmic rays coming from the Galaxy, before they can reach the Earth." :
http://www.spacecenter.dk/research/sun-climate
100,000-Year Climate Pattern Linked To Sun's Magnetic Cycles:
ScienceDaily (Jun. 7, 2002) HANOVER, N.H.
Thanks to new calculations by a Dartmouth geochemist, scientists are now looking at the earth's climate history in a new light. Mukul Sharma, Assistant Professor of Earth Sciences at Dartmouth, examined existing sets of geophysical data and noticed something remarkable: the sun's magnetic activity is varying in 100,000-year cycles, a much longer time span than previously thought, and this solar activity, in turn, may likely cause the 100,000-year climate cycles on earth. This research helps scientists understand past climate trends and prepare for future ones.
http://www.sciencedaily.com/releases/2002/06/020607073439.htm
So, in other words, your study proves exactly nothing regarding anthropogenic global warming.
Of course.
But also you realize, of course, that such a view does nothing to contradict the idea that carbon dioxide could be leading to global warming....right?
After all, it's not like we have an example from the past in which man pumped CO2 into the atmosphere at our current rate, raising the atmospheric concentration to its current level (that is, raising it above the quasiequilibrium level and potentially making CO2 become a forcing element, not reactive). It's not like Homo erectus was buring THAT much stuff, even after discovering fire! :-)
Additionally, the temperature increase could very well have been the result of feedbacks, following initiation by a change in insolation.
Nope. This is the first I heard of it. It just amazed me that the core goes back 800Kyr. I thought EPICA was about as far as it would get.
The best natural analogue, well out of reach of ice core but not oceanic sediment cores, is the Paleocene-Eocene Thermal Maximum. It occurred over much longer time-scales, but it did show the expected cause-and-effect relationship.
I recall reports of EPICA being back 800K a while ago, but hadn’t seen details. Looks like it was true. :-)
I thought that the latest on the PETM was that the temperature signal preceded.
No mention of what happened 800,001 years ago.
ping
Anyone who has taken lessons for Scuba diving knows that gases are absorbed and released into and out of water quite freely depending on temperature and pressure. With all due respect to people who stayed in college longer than did I, I cannot help but think that this trapped CO2 they are measuring must migrate in the ice.
It it not “trapped” in the ice like one traps a bug in a sealed bottle. It is free to move, and indeed it has had 800,000 years to move.
I would be interested in details about how this group of scientists have firmly resolved the issue of CO2 v temperature change. Which came was the leading variable in upward temperature movement and then which was leading in downward movements?
If you've got time (I don't right now), find the reference and educate me!
Oh, no? There were at least two prior times in the geologic record (450 million and ~180 million) when CO2 levels were over ten times what they are now and they were both during major cold spells. (the top graph shows CO2 concentrations, the bottom, temperatures)
"The above chart shows the range of global temperature through the last 500 million years. There is no statistical correlation between the level of carbon dioxide in the atmosphere through the last 500 million years and the temperature record in this interval. In fact, one of the highest levels of carbon dioxide concentration occurred during a major ice age that occurred about 450 million years ago. Carbon dioxide concentrations at that time were about 15 times higher than at present.":
http://www.tcsdaily.com/article.aspx?id=010405M
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