Big freeze plunged Europe into ice age in months

Nov 30, 2009

In the film, 'The Day After Tomorrow' the world enters the icy grip of a new glacial period within the space of just a few weeks. Now new research shows that this scenario may not be so far from the truth after all.

William Patterson, from the University of Saskatchewan in Canada, and his colleagues have shown that switching off the North Atlantic circulation can force the into a mini 'ice age' in a matter of months. Previous work has indicated that this process would take tens of years.

Around 12,800 years ago the northern hemisphere was hit by a mini ice-age, known by scientists as the Younger Dryas, and nicknamed the 'Big Freeze', which lasted around 1300 years. Geological evidence shows that the Big Freeze was brought about by a sudden influx of freshwater, when the glacial Lake Agassiz in North America burst its banks and poured into the North Atlantic and Arctic Oceans. This vast pulse, a greater volume than all of North America's Great Lakes combined, diluted the North Atlantic conveyor belt and brought it to a halt.

Without the warming influence of this temperatures across the Northern hemisphere plummeted, ice sheets grew and human civilisation fell apart.

Previous evidence from Greenland ice cores has indicated that this sudden change in climate occurred over the space of a decade or so. Now new data shows that the change was amazingly abrupt, taking place over the course of a few months, or a year or two at most.

Patterson and his colleagues have created the highest resolution record of the 'Big Freeze' event to date, from a mud core taken from an ancient lake, Lough Monreach, in Ireland. Using a scalpel layers were sliced from the core, just 0.5mm thick, representing a time period of one to three months.

Carbon isotopes in each slice reveal how productive the lake was, while oxygen isotopes give a picture of temperature and rainfall. At the start of the 'Big Freeze' their new record shows that temperatures plummeted and lake productivity stopped over the course of just a few years. "It would be like taking Ireland today and moving it up to Svalbard, creating icy conditions in a very short period of time," says Patterson, who presented the findings at the European Science Foundation BOREAS conference on humans in the Arctic, in Rovaniemi, Finland.

Meanwhile, their isotope record from the end of the Big shows that it took around two centuries for the lake and climate to recover, rather than the abrupt decade or so that ice cores indicate. "This makes sense because it would take time for the ocean and atmospheric circulation to turn on again," says Patterson.

Looking ahead to the future Patterson says there is no reason why a 'Big Freeze' shouldn't happen again. "If the Greenland ice sheet melted suddenly it would be catastrophic," he says.

Source: European Science Foundation (news : web)

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tpb
3.7 / 5 (6) Nov 30, 2009
Quote
"If the Greenland ice sheet melted suddenly it would be catastrophic,"

Yes it would, but it can't.
R_R
1.7 / 5 (6) Nov 30, 2009
Polar ice sheets would melt rapidly under certain conditions. One condition would be large meteor impacts. I firmly believe that one of these catastrophic impacts took place in 10,500 BC on the Ice Age ice sheets at Hudson Bay. Understanding the amount of heat and ice displacement (Carolina Bays),this could quite possibly place all the ducks in a row to account for the rapid melting of ice. The severity of the impact I am discussing had the power to cause Pole Shift that repositioned these ice fields to a lower latitude causing the meltings completion. There is much more evidence to support this theory at www.thegreatpyramidspeaks.com . Happy to see this is being discussed.
omatumr
1.8 / 5 (5) Nov 30, 2009
Has global warming already been replaced by global cooling?
DGBEACH
3.7 / 5 (3) Dec 01, 2009
Has global warming already been replaced by global cooling?

Well evidently you have to watch the movie "The day after tomorrow" to understand. However in the movie it was those "holes in the atmosphere" produced by massive weather systems (?) which cooled things down so quickly...but that's not the way things really work, is it.
So which "huge glacial lake" would be bursting its banks THIS time? Are there even any left? How quickly can ALL THAT ICE actually melt? Obviously not fast enough to cause what they're suggesting.
Scare mongers!
toyo
4.8 / 5 (5) Dec 01, 2009
All kudos to Patterson and friends, but I remain sceptical about how much can be read into data derived, no matter how accurately, from: "a mud core taken from an ancient lake".
I have not read his work and there is no link to it, so I cannot check, but if, as is implied by the above, there was ONE sample from ONE lake, I'm afraid I'm not buying it.
IMHO it'll take a lot more samples from a lot more places to characterise accurately an event that spanned the whole of the Northern hemisphere.
Local variances have been shown to be rather large, and 'ONE swallow does not a summer make'.

PS DGBEACH, A glacial lake is not a lake full of ice, it's one fed by a glacier. :)
DGBEACH
5 / 5 (1) Dec 01, 2009
PS DGBEACH, A glacial lake is not a lake full of ice, it's one fed by a glacier. :)
...duh
Since there are no glacial lakes left which could quickly dilute the oceans with fresh water, as happened 12800 yrs ago, we will have to wait until the glaciers melt. My question is how long will that take!
R_R
1.8 / 5 (5) Dec 01, 2009
Then-North America covered in ice while directly on the other side of todays pole in Siberia millions of Elephants and other mammals living comfortably.

Now-North America ice free and Siberia permanently frozen with complete Mammoth carcasses continually surfacing.

What is the explanation from these geniuses who apperently have all the answers?

People that are passionate about finding the real answers will take the time to read and consider all new information with one common goal, to eventually end up with resonable explanations of facts being discussed. Unfortunatly it appears to me that the drivers behind the information highway is more monetary than factual. Our society has been spoon fed information to reduce our capacity in auctually thinking for ourselves. Unfortunatally I view our society as a bunch of sheep with bells being herded on by the all masterful sheep dog and I for one am making a break for it. Ba Ba for now.