Posted on 05/08/2005 8:21:59 AM PDT by velyrorenry
CLIMATE change researchers have detected the first signs of a slowdown in the Gulf Stream the mighty ocean current that keeps Britain and Europe from freezing.
They have found that one of the engines driving the Gulf Stream the sinking of supercooled water in the Greenland Sea has weakened to less than a quarter of its former strength.
The weakening, apparently caused by global warming, could herald big changes in the current over the next few years or decades. Paradoxically, it could lead to Britain and northwestern and Europe undergoing a sharp drop in temperatures.
Such a change has long been predicted by scientists but the new research is among the first to show clear experimental evidence of the phenomenon.
Peter Wadhams, professor of ocean physics at Cambridge University, hitched rides under the Arctic ice cap in Royal Navy submarines and used ships to take measurements across the Greenland Sea.
Until recently we would find giant chimneys in the sea where columns of cold, dense water were sinking from the surface to the seabed 3,000 metres below, but now they have almost disappeared, he said.
As the water sank it was replaced by warm water flowing in from the south, which kept the circulation going. If that mechanism is slowing, it will mean less heat reaching Europe.
Such a change could have a severe impact on Britain, which lies on the same latitude as Siberia and ought to be much colder. The Gulf Stream transports 27,000 times more heat to British shores than all the nations power supplies could provide, warming Britain by 5-8C.
Wadhams and his colleagues believe, however, that just such changes could be well under way. They predict that the slowing of the Gulf Stream is likely to be accompanied by other effects, such as the complete summer melting of the Arctic ice cap by as early as 2020 and almost certainly by 2080. This would spell disaster for Arctic wildlife such as the polar bear, which could face extinction.
Wadhamss submarine journeys took him under the North Polar ice cap, using sonar to survey the ice from underneath. He has measured how the ice has become 46% thinner over the past 20 years. The results from these surveys prompted him to focus on a feature called the Odden ice shelf, which should grow out into the Greenland Sea every winter and recede in summer.
The growth of this shelf should trigger the annual formation of the sinking water columns. As sea water freezes to form the shelf, the ice crystals expel their salt into the surrounding water, making it heavier than the water below.
However, the Odden ice shelf has stopped forming. It last appeared in full in 1997. In the past we could see nine to 12 giant columns forming under the shelf each year. In our latest cruise, we found only two and they were so weak that the sinking water could not reach the seabed, said Wadhams, who disclosed the findings at a meeting of the European Geosciences Union in Vienna.
The exact effect of such changes is hard to predict because currents and weather systems take years to respond and because there are two other areas around the north Atlantic where water sinks, helping to maintain circulation. Less is known about how climate change is affecting these.
However, Wadhams suggests the effect could be dramatic. One of the frightening things in the film The Day After Tomorrow showed how the circulation in the Atlantic Ocean is upset because the sinking of cold water in the north Atlantic suddenly stops, he said.
The sinking is stopping, albeit much more slowly than in the film over years rather than a few days. If it continues, the effect will be to cool the climate of northern Europe.
One possibility is that Europe will freeze; another is that the slowing of the Gulf Stream may keep Europe cool as global warming heats the rest of the world but with more extremes of weather.
Thomas Sowell: Intellectuals often mistake confusion in their own minds with complexity in the real world.
Point is, global warming has become so hopelessly politicized by people who want to use it as a wedge to promote their own ridiculous Luddite schemes that any inconsistencies or counterintuitive arguments appear risible on their face and are greeted therefore with derision.
You can't have it both ways. Either Britain will become a tropical garden or tundra, but not both. Let me know when you make up your mind.
I saw that movie. It sucked. Big time.
According to the theory proposed by Felix, the increase in volcanic activity (along with a magnetic reversal of the poles) is linked to the onset of a new ice. This has been going on for millions of years with a new ice age occurring every 10,000 years. We are due for another one now.
Over the last 700,000 years actually the periodicity is 100,000 years, interrupted with 10,000 years,on average, of warm period,
Ice Ages & Astronomical Causes
Figure 1-5 Climate for the last 420 kyr, from Vostok ice
From this plot, it is clear that most of the last 420 thousand years (420 kyr) was spent in ice age. The brief periods when the record peaks above the zero line, the interglacials, typically lasted from a few thousand to perhaps twenty thousand years. See also: Origin of the 100 kyr Glacial Cycle & Spectrum of 100-kyr glacial cycle: Orbital inclination, not eccentricity
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this is mainly related to astronomical factors relating to variations in the Earth's orbit more than geological reasons.
Looking back 1 million years and more, even that picture changes drastically, primarily due to continental drift and similar effects happening on the wider geological scales of time.
Ice Ages & Astronomical Causes
The ice records take us back only to 420,000 years in the past. However, oxygen isotope records in sea floor cores allow us to go further. One of the best sets of data comes from a location in the northern Atlantic Ocean known as the Ocean Drilling Project Site 607 . This site has climate data going back three million years, and is shown in Figure 1-6. But before you look at the figure, let us warn you. In the paleoclimate community, there is a convention that time is shown backwards. That is, the present is plotted on the left-hand edge, and the past is towards the right. We are going to use this opportunity to change our convention, for the remainder of the book, so that you will have less trouble reading the literature. (The literature of "global warming" scientists, in contrast, follows the other convention, which we have used up until now.) We apologize for this change in convention, but we do not take blame for it. In Figure 1-6, the 10 kyr years of agriculture and civilization appear as a sudden rise in temperature barely visible squeezed against the left hand axis of the plot. The temperature of 1950 is indicated by the horizontal line. As is evident from the data, civilization was created in an unusual time. There are several important features to notice in these data, all of which will be discussed further in the remainder of the book. For the last million years or so (the left most third of the plot) the oscillations have had a cycle of about 100 kyr (thousand years). That is, the enduring period of ice is broken, roughly every 100 kyr, by a brief interglacial. During this time, the terminations of the ice ages appear to be particularly abrupt, as you can see from the sudden jumps that took place near 0, 120, 320, 450, and 650 thousand years ago. This has led scientists to characterize the data as shaped like a "sawtooth," although the pattern is not perfectly regular. Figure 1-6 Climate of the last 3 million years But as we look back beyond a 1000 kyr (1 million years), the character changes completely. The cycle is much shorter (it averages 41 kyr), the amplitude is reduced, the average value is higher (indicating that the ice ages were not as intense) and there is no evidence for the sawtooth shape. These are the features that ice age theories endeavor to explain. Why did the transition take place? What are the meanings of the frequencies? (We will show that they are well-known astronomical frequencies.) In the period immediately preceding the data shown here, older than 3 million years, the temperature didnt drop below the 1950 value, and we believe that large glaciers didnt form perhaps only small ones, such as we have today in Greenland and Antarctica. |
Looking back beyond the 3 million year window, we find a much different pattern of events and global temperatures which have roots in continental drift and potentially our position in the galactic arms as we swing in and out of galactic dust clouds and variations in cosmic ray flux in the disc of our Galaxy.
Global Surface 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 |
Ok: do most scientists agree that Global Warming exists or not?
What kind of scientists, Political or those involved in the acutal emperical study of the field of paleoclimatology and atmospheric sciences?
Physical science is not subject to a vote or concensus, that's politics. Physical science is a matter of the scientific method, observation through physical measurement, and hypothesis tested in the observations of further physical measurement in the test of the predictions of hypothesis.
"Facts are stubborn things; and whatever may be our wishes, our inclination, or the dictates of our passions, they cannot alter the state of facts and evidence."
--John Adams
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.
Global warming and global cooling exist due to natural causes. Depends on your time frame as to whether you can use it for a political agenda rather than science.
Politics controls the hype, physical data measurement controls the physical reality:
"Carbon dioxide, the main culprit in the alleged greenhouse-gas warming, is not a "driver" of climate change at all. Indeed, in earlier research Jan Veizer, of the University of Ottawa and one of the co-authors of the GSA Today article, established that rather than forcing climate change, CO2 levels actually lag behind climatic temperatures, suggesting that global warming may cause carbon dioxide rather than the other way around."
***
"Veizer and Shaviv's greatest contribution is their time scale. They have examined the relationship of cosmic rays, solar activity and CO2, and climate change going back through thousands of major and minor coolings and warmings. They found a strong -- very strong -- correlation between cosmic rays, solar activity and climate change, but almost none between carbon dioxide and global temperature increases."
Climatic temperature is predominantly driven by Solar heating/cooling arising from variation of solar irradiance, due variations in distance from the Sun, and Solar radiance,
Global Warming on Triton (Neptune's moon)
plus variations in Earth's orbital alignment with mean solar system plane and geophysical events affecting planetary albedo.
Ice Ages & Astronomical Causes Origin of the 100 kyr Glacial Cycle Figure 1-1 Global warming Figure 1-2 Climate of the last 2400 years Figure 1-3 Climate of the last 12,000 years Figure 1-4 Climate of the last 100,000 years Figure 1-5 Climate for the last 420 kyr, from Vostok ice |
http://newton.ex.ac.uk/aip/physnews.252.html#1
INTERPLANETARY DUST PARTICLES (IDPs) are deposited on the Earth at the rate of about 10,000 tons per year. Does this have any effect on climate? Scientists at Caltech have found that ancient samples of helium-3 (coming mostly from IDPs) in oceanic sediments exhibit a 100,000-year periodicity. The researchers assert that their data, taken along the Mid-Atlantic Ridge, support a recently enunciated idea that Earth's orbital inclination varies with a 100-kyr period; this notion in turn had been broached as an explanation for a similar periodicity in the succession of ice ages. (K.A. Farley and D.B. Patterson, Nature, 7 December 1995.)
Farley & Patterson 1998, http://www.elsevier.com/gej-ng/10/20/36/33/37/32/abstract.html
Farley http://www.gps.caltech.edu/~farley/
Farley http://www.elsevier.nl/gej-ng/10/18/23/54/21/49/abstract.html
http://www.publicaffairs.noaa.gov/pr96/dec96/noaa96-78.html
ABRUPT CLIMATE CHANGE DURING LAST GLACIAL PERIOD COULD BE TIED TO DUST-INDUCED REGIONAL WARMING
Preliminary new evidence suggests that periodic increases in atmospheric dust concentrations during the glacial periods of the last 100,000 years may have resulted in significant regional warming, and that this warming may have triggered the abrupt climatic changes observed in paleoclimate records, according to a scientist at the Commerce Department's National Oceanic and Atmospheric Administration. Current scientific thinking is that the dust concentrations contributed to global cooling.
I'm confused, how did Bush cause all of this 100,000,000 years ago.
The acutal interval between ice ages is 11,500 years over the last 500,000 years.
The periodicity of those intervals, on the otherhand relates directly to the 100kyr period of the inclination of earths orbit to the planetary mean.
The issue being what allows for the increase in temperature for approximately 10kyrs, out of each 100,000 years when most of the earths orbit lies outside of the planetary accretion(i.e. dust) disc of the mean solar orbit.
Spectrum of 100-kyr glacial cycle: Orbital inclination, not eccentricity Origin of the 100 kyr Glacial Cycle
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http://newton.ex.ac.uk/aip/physnews.252.html#1
INTERPLANETARY DUST PARTICLES (IDPs) are deposited on the Earth at the rate of about 10,000 tons per year. Does this have any effect on climate? Scientists at Caltech have found that ancient samples of helium-3 (coming mostly from IDPs) in oceanic sediments exhibit a 100,000-year periodicity. The researchers assert that their data, taken along the Mid-Atlantic Ridge, support a recently enunciated idea that Earth's orbital inclination varies with a 100-kyr period; this notion in turn had been broached as an explanation for a similar periodicity in the succession of ice ages. (K.A. Farley and D.B. Patterson, Nature, 7 December 1995.)
Farley & Patterson 1998, http://www.elsevier.com/gej-ng/10/20/36/33/37/32/abstract.html
Farley http://www.gps.caltech.edu/~farley/
Farley http://www.elsevier.nl/gej-ng/10/18/23/54/21/49/abstract.html
http://www.publicaffairs.noaa.gov/pr96/dec96/noaa96-78.html
ABRUPT CLIMATE CHANGE DURING LAST GLACIAL PERIOD COULD BE TIED TO DUST-INDUCED REGIONAL WARMING
Preliminary new evidence suggests that periodic increases in atmospheric dust concentrations during the glacial periods of the last 100,000 years may have resulted in significant regional warming, and that this warming may have triggered the abrupt climatic changes observed in paleoclimate records, according to a scientist at the Commerce Department's National Oceanic and Atmospheric Administration. Current scientific thinking is that the dust concentrations contributed to global cooling.
Yeah, but the wines man think about the wines.
I'm confused, how did Bush cause all of this 100,000,000 years ago.
A Bush ancestor did it. Remember the story of Moses and the burning Bush?
Cause all kinds of havoc, so the story goes. ;O)
Canadian wine will just have to do.
Yah nothing like that Montreal champaign--shudder.
I appreciate the graphs and charts, but can you explain in layman's language the difference or seeming inconsistency between the Climap contention that ice ages begin or end, almost like clockwork, every 11,500 years, i.e., it's a dependable, predictable, natural cycle--Pacemaker of the Ice Ages, they called it and Muller's Glacial 100 kyr Glacial Cycle.
Glaciation is a combination of local phenomena as well as global climate changes of the earth as a whole, move the local land mass, there is a change in orientation of the magnetic record recorded in the surface for different periods. And yes amount of local glaciation as well.
And yes magnetic poles do wander, and there is an effect on incidence of cosmic radiation and hence cloud cover, a phenomena well observed. Thus one would expect a consequent local variation in local glacial coverage as the pole wanders around a mean as cloud cover over local regions change.
Global climate patterns, as a consequence of total heating and cooling of the atmosphere and surface of landmass as a whole is another thing altogether.
"Global" climate change is a distinctly different phenomena from variation of temperature as it is averaged across the entire surface of the planet that "global" warming phenomena are concerned with.
Is this a reply to my question? If so, you still have not answered it.
Will compasses point south? No, this headline doesnt come from some supermarket tabloid, it comes from the New York Times and it backs up what Ive been saying for years that we are headed for a geomagnetic reversal.
Magnetic field strength has waned 10 to 15 percent over the past 150 years, the article says, and the deterioration has accelerated. The fact that it (magnetic field strength) is dropping so rapidly gives you pause, says Dr. John A. Tarduno, professor of geophysics at the University of Rochester. The odds of a reversal are more likely than not, says Tarduno. (New York Times, July 13, 2004, by William J. Broad) http://www.nytimes.com/2004/07/13/science/13magn.html
The article goes on to say that the last magnetic reversal occurred some 780,000 years ago, and that there is no correlation between magnetic reversals and extinctions. I disagree with both of those contentions. I have evidence that there have been at least eleven magnetic reversals in the past 780,000 years - probably many more. I also have evidence that extinctions and reversals do in fact go hand-in-hand.
* * *
Link between ice ages and magnetic reversals
That there is a link between magnetic reversals and ice ages is undeniable.
At least twelve magnetic reversals can be linked to glaciation during the last three million years alone.
A magnetic reversal about three million years ago marked the onset of glaciation. A magnetic reversal about two million years ago marked the onset of glaciation. And yet another reversal about one million years ago marked the onset of glaciation.
The Jaramillo magnetic reversal maked the onset of glaciation, as did the Brunhes magnetic reversal.
The Biwa I, Biwa II, Biwa III, and Blake (at the end Eemian) magnetic reversals coincided with glaciation, and so did the Lake Mungo, Mono Lake, and Gothenburg magnetic reversals (or excursions).
Many of those catastrophic cooling episodes, says Michael Rampino of NASA, may have actually been triggered by the magnetic reversal (or excursion).
Why should this concern us?
Several reasons:
One: We appear to be headed for another magnetic reversal right now. During the past 2000 years, magnetic field strength has fallen some 50 to 65 percent. Unfortunately, the rate of decline is picking up. Five percent of the decline has occurred during the last 100 years alone. This decline, say geophysicists, may be a precursor to a new reversal attempt.
Two: When ice ages begin, they begin incredibly fast. At the end Eemian, for example, the climate descended from a period of warmth such as today's - such as today's - into full-blown glacial severity in less than twenty years.
Three: I think we're headed into such a twenty-year period right now.
Four: The North Magnetic Pole is moving! "The magnetic pole, which has steadily drifted for decades, has picked up its pace in recent years and could exit Canadian territory as soon as 2004," said Larry Newitt of the Geological Survey of Canada. "It's speed has increased considerably during the past 25 years," the geophysicist said. See: CNN.com - North Magnetic Pole - March 20, 2002.
Five: According to John Tarduno, professor of geophysics at the Univerity of Rochester (NY), the next magnetic reversal could occur within a matter of centuries.
Tarduno based his findings on detailed studies of the Earth's magnetic field made during four trips above the Arctic Circle. (Published in the Proc. of the National Academy of Sciences, 16 Oct 2002.) See also: www.rochester.edu/pr/News/NewsReleases/latest/tarduno-cylinder.html
_______________________________
Ice ages also correlate with magnetic activity on the Sun.
According to Mukul Sharma, Assistant Professor of Earth Sciences at Dartmouth, the Sun displays a 100,000-year cycle of magnetic activity that corresponds to the Earth's ice age history.
Sharma's calculations suggest that when the Sun is magnetically more active, the Earth experiences a warmer climate, and vice versa, when the Sun is magnetically less active, there is a glacial period. Right now, the Earth is in an interglacial period (between ice ages). This is also a time of high solar activity.
This cycle appears to match the 100,000-year ice-age cycle first theorized by Milutin Milankovitch, which suggests that ice ages correspond to the cyclical varations in the Earth's orbit around the Sun. (Earth & Planetary Science Ltrs, Vol. 199, issues 3-4, June 10, 2002)
(One of the methods Sharma used to determine historic magnetic activity on the Sun was through the study of berillium 10, which I thoroughly agree with. In fact, I mention berillium 10 production several times in my book.)
(See Not by Fire but by Ice for more citations.)
Thanks for the ping
lots of knew info has been added since the thread started.
Well yes I do understand now, a burning bush would create heat. Kind of explains why the Arabs seem to still be pissed off at the Bush family.
I appreciate the graphs and charts, but can you explain in layman's language the difference or seeming inconsistency between the Climap contention that ice ages begin or end, almost like clockwork, every 11,500 years, i.e., it's a dependable, predictable, natural cycle--
A glaciation in specific place may last 11,500 years, as an average, that is not the same as repeating every 100,000 years of the deep ice age cycle, nor is glaciation in particular place an indicator of "global" scope per-se.
The second factor is that you can have two cyclical effects simultaneously, a lessor one superimposed over a large one.
Note the deep ice age periods vary, albeit offset at a lower temperature level.
Figure 1-4 Climate of the last 100,000 years
As opposed to the major 100kyr cycles of induced by astronomic factors:
Figure 1-5 Climate for the last 420 kyr, from Vostok ice
Figure 1-5 Climate for the last 420 kyr, from Vostok ice
It should be considered if indeed the "claims" of the website have any validity beyond picking specific data points to bolster a shaky hypothesis.
It is easy to claim a thing on a website, and another altogether to stand up to critical scrutiny with all factors considered.
(One of the methods Sharma used to determine historic magnetic activity on the Sun was through the study of berillium 10, which I thoroughly agree with. In fact, I mention berillium 10 production several times in my book.)
Be10 is an indicator of overall solar activity which results in variation in solar brightness as well as variation of cosmic ray densities that are a significant factor in the formation of cloud cover on the earth affecting total incident radiation at surface level warming the earth on a global basis.
Variations of the magnetic field of the earth can cause variations in cosmic ray density over the earth and hence variation in global cloud coverage which can induce the same kind of effects.
What I question is this 11,500 year number as a periodic phenomena that is claimed.
I cerainly see no evidence in the polar ice BE10 data, that is the primary proxy for temperature that is repesented in the artic and antartic icecore data either in its raw from available on the net or the graphical form it has been presented in Muller's paper.
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