Looks to me like the recent geological history is showing that Earth is in a comparitive deep freeze compared to the rest of the time life has been on earth.
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 nation’s 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.
Wadhams’s 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.
Years ago, I read descriptions of London that talked of the Thames being frozen in winter and the Londoners having fairs on the river. It sounds as though Britain, now that the industrial age is past, is going to return to it's true weather patterns.
Is this a reply to my question? If so, you still have not answered it.
#134 was in response to your #126 post of website making a number of claims though little in what I would recognize as hard data or analysis.
My #139 is in response to your question from #133.
A little patience goes along way. One does not necessarily sit on a forum continuously, there are more than one call on one's time. And I do not consider Global Warming as my most important task to answer to.
Save as many as you can.
Looks to me like the recent geological history is showing that Earth is in a comparitive deep freeze compared to the rest of the time life has been on earth.
| http://www.climateark.org/articles/reader.asp?linkid=24095
Galactic dust cooling Earth? Shaviv and climatologist Ján Veizer of Ruhr University, Germany, reckon that the spiral arms of our galaxy hold the secret to the Earth's see-sawing climate. Every 150 million years, blasts of cosmic rays cool the planet on its stately passage through the cosmos, they argue2. *** SNIP *** Shaviv attempts to explain how the Sun's natural variability affects the number of cosmic rays hitting the Earth, says Harrison. The Sun also produces radiation similar to cosmic rays, especially at the hottest part - called the solar maximum - of its 11-year cycle. Previous studies have failed to tease apart the climatic impacts of this radiation, of cosmic rays from the galaxy, and of warmth from the Sun. |
See the research at CERN in the proposed CLOUD study alluded to in the above article
See also, Svensmark: ==>COSMIC RAYS AND EARTH'S CLIMATE
It should be mentioned that this would almost assuredly make the northeast U.S. get colder as well.
Though this is not a big issue. Yeah, it will get a bit colder, but nothing to panic about.
Sorry if my question sounded like I was impatient. Since you didn't indicate what you were replying to, I was just seeking a clarification. You can resond or not respond in your own good time. I don't sit on the forum continuously either.
Based on the graphs, it appears that over the last 420 kyrs (Vostok Ice) a fairly regular pattern emerges. If that is the case, we should see a fairly precipitous drop in temperature in the not too distant future.
Whoaooo! Best post I've read in months! You've done my debate research for me.
Based on the graphs, it appears that over the last 420 kyrs (Vostok Ice) a fairly regular pattern emerges. If that is the case, we should see a fairly precipitous drop in temperature in the not too distant future.
Very possibly in geological terms, though the time scale of the graph can leave 5-10 centuries(a pixelwidth) in which such a move could develop. That is one of the problems with most graphs in geological time scales on a computer, one looses sight of what a single pixel can represent. A lot can happen in a millenium.
A more uptodate paper on glacial cycles, a collaboration of J. Kirkby, of the CERN CLOUD project, and Dr. Muller's work in Astronomical relationships attempting to bring the effects of changes in the shorter term geomagnetic effects adn100kyr astrophysical effects on cosmic ray flux together.
The glacial cycles and cosmic raysAuthors: J. Kirkby, A. Mangini, R.A. Muller
Full Text PDF: http://www.arxiv.org/PS_cache/physics/pdf/0407/0407005.pdf |
You've done my debate research for me.
Wait till you get through #123 and beyond, there's more. LOL
I did, thanks.
Since you didn't indicate what you were replying to
A place to look, is on the bottom line of any comment, in the links part:
==> [ Post Reply | Private Reply | To 142 | View Replies | Report Abuse ]
The | To 142 | in this case for your comment, is a link pointing to the comment being replied to.
Under this reply you will likewise find a similar link | To 148 | to the comment you authored that this reply is for.
Neat huh??? John Robinson done good in the bells & whistles department :O)
Thanks. It took me several years to learn that one.
No need for spin, numbers are numbers.
That would hardly be definitive...for example, if the sun is actually hotter now, it would be driving CO2 out of solution from the oceans.
The main heat trapping gas is water vapor...which varies according to a great many factors, from ambient temperature to land-mass distribution, to weather patterns, and so forth.
Beans..
Weather back home ping!
Which isn't saying too much.
Dropping the Kyoto requirements for particulates might be a simple step. Teller noted several ideas a few years ago, most of which were less than a Billion dollars a year, by which the entire globe could be cooled.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.