Posted on 05/13/2003 10:19:07 PM PDT by EdZ
We have learned much about the workings of natural sinks like the oceans and terrestrial plants, but are just beginning to understand how their behavior might change as atmospheric CO2 concentrations rise.
Organic carbon buried in sediments as coal, natural gas, and oil over literally hundreds of millions of years is being consumed as a result of human activities and returned to the atmosphere as carbon dioxide (CO2) on a time scale of a few centuries... Because of anthropogenic emissions, atmospheric CO2 has climbed to levels that are presently more than 30% higher than before the industrial revolution,1,2 as seen in figure 2. Indeed, geochemical measurements made on ancient ocean sediments suggest that atmospheric CO2 levels over the past 20 million years were never as high as they are today.3
The increase in atmospheric CO2 has drawn a great deal of attention because of the impact it has on the trapping of long wavelength radiation emitted from Earth's surface. More than half of the increase in the direct trapping that has occurred since preindustrial times is attributed to CO2, with the rest coming from other gases such as methane, nitrous oxide, and chlorofluorocarbons. The effect of this increased trapping on Earth's climate depends on a number of complex feedbacks. Nevertheless, the strong consensus of the scientific community is that the increased trapping will lead to global warming; it probably accounts for most of the 0.6 ± 0.2 °C warming that occurred during the last century.3 Humankind thus appears to be playing a significant role in altering Earth's climate.
(Excerpt) Read more at aip.org ...
The above article also discusses how natural carbon sinks will respond to global climate change.
http://www.junkscience.com/news/robinson.htm
http://www.ncpa.org/ba/ba230.html
it [CO2] probably accounts for most of the 0.6 ± 0.2 °C warming that occurred during the last century
This statement is where I depart from the article.
I have no disagreement that human activities have raised the CO2 level by a measurable amount, although I suspect that a full accounting for agriculture and animal husbandry as sources of greenhouse gasses would exonerate the much-maligned SUV as a primary culprit.
However a connection between greenhouse gases and global warming that fails to take into account the variation in the sun's energy output is fundamentally flawed.
It appears that the earth's surface has been both warmer and colder than it presently is in the past few thousand years. Any connection between these natural temperature variations and human activity is clearly erroneous.
Whether the current warming is caused by human activity or natural processes is not at all clear.
The concept of tying our economy in a knot on the basis of fragmentary information and quite possibly erroneous conclusions is the height of foolishness.
. Indeed, geochemical measurements made on ancient ocean sediments suggest that atmospheric CO2 levels over the past 20 million years were never as high as they are today.
Why stop at 20 million years?
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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But the the lack of a cause effect nexus from CO2 to temperature is abit of concern too!
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The increase in atmospheric CO2 has drawn a great deal of attention because of the impact it has on the trapping of long wavelength radiation emitted from Earth's surface.
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
The reality is a doubling of atmospheric CO2 concentration over current levels, that the IPCC "story line" pretends, even if true, could not induce significant temperature change whatever its source.
A Lukewarm Greenhouse
"The average warming predicted by the six methods for a doubling of CO2, is only +0.2 degC."
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."
Nevertheless, the strong consensus of the scientific community is that the increased trapping will lead to global warming;
Consensus, maybe among the Political Science community.
Those actually within the applied sciences dealing with facts instead of imagination, seem to have a somewhat different view of things:
Petition Project: http://www.oism.org/pproject/s33p357.htm
During the past 2 years, more than 17,100 basic and applied American scientists, two-thirds with advanced degrees, have signed the Global Warming Petition.
Specifically declaring:
"There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gasses is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate."
Signers of this petition so far include 2,660 physicists, geophysicists, climatologists, meteorologists, oceanographers, and environmental scientists (select this link for a listing of these individuals) who are especially well qualified to evaluate the effects of carbon dioxide on the Earth's atmosphere and climate.
Signers of this petition also include 5,017 scientists whose fields of specialization in chemistry, biochemistry, biology, and other life sciences (select this link for a listing of these individuals) make them especially well qualified to evaluate the effects of carbon dioxide upon the Earth's plant and animal life.
Nearly all of the initial 17,100 scientist signers have technical training suitable for the evaluation of the relevant research data, and many are trained in related fields.
atmospheric CO2 levels over the past 20 million years were never as high as they are today.
Of course the altenative question becomes, why were temperatures higher than they are today during those same last 20 million years? Even within the last 700 thousand years. Note as well that CO2 tends to change after the change in temperature starts, both rising and falling.
This may come as a shock to many Americans, but burning fossil fuels is causing atmospheric carbon dioxide to increase.
Fossil fuels release less than 4% of the total CO2 coming from other sources, and once more:
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
CO2 is great for growing more forests and reclaiming deserts:
Greenhouse Gas Might Green Up The Desert;
Weizmann Institute
Seems the more gets pumped in the greener it gets, sinking Carbon out of the atmosphere more rapidly, seems the Global Warming folks always want to ignore the benefits and the sinks, concentrating more on sources for political kick.
Climatic temperature change OTOH generally gives rise to changes in atmospheric CO2 concentration through changes of biomass, warming of ocean with release of CO2 from solution with rising temperatures.
6.4.1.1. Sources of Atmospheric CO2
Sources of atmospheric CO2 can today be divided into two groups: natural and anthropogenic. Natural sources include the respiration of animals (60Gt per annum) and the surface ocean (90Gt per annum) (Schimel et al., 1995). Anthropogenic sources include the combustion of fossil fuels (power stations and transport) and cement production (5.5Gt per annum)and land-use changes (mainly deforestation) (1.6Gt per annum)
6.4.1.2. Sinks of Atmospheric CO2
The surface ocean also acts as a natural sink for atmospheric CO2, with an annual removal flux of 92Gt carbon. The interaction of CO2 between atmosphere and surface ocean was more fully addressed in section 5.3.1.2 (Equations 14 to 17). The other major natural sink is the primary productivity of land vegetation (photosynthesis), which sequesters 61.4Gt carbon every year (Schimel et al., 1995). The regrowth of Northern Hemisphere forests represents the only major anthropogenic sink of atmospheric CO2, although enhanced fertilisation effects due to elevated CO2 concentrations and other climatic feedbacks have also been considered.
This may come as a shock to many Global Warming hucksters but your fearless leader, James Hansen, has decided that CO2 emissions from fossil fuels ARE NOT the primary cause of global warming:
Carping about CO2 from fossil fuels is, like, soooooo 1990s.
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