Monday, April 5, 2010

Mega Flood Lake Agassiz




I have posted extensively on the topic of the events that took place around 11,000 to 13,000 years ago.  A lot of evidence supports the idea of a crustal shift triggered by a comet impact into the ice cap close by the then North Pole position.  Some of it is direct but a huge amount of the evidence is indirect or inferential.

Most telling is that a direct crustal shift does end the million year Ice Age while nothing else does.  In addition the ice is exactly were it belongs and the geological evidence is then in the right place geographically.

All the good direct evidence is long since lost under three hundred feet of water.

This article discusses the collapse of Lake Agassiz.  The assumption is that the collapse triggered a cooling spell which is quite reasonable.  It would have taken centuries for ocean temperatures to normalize.

It also seems reasonable for the crustal shift to create the necessary conditions for the creation of the lake itself.  That may not be true at all.  The land barrier would become much more secure if the lake formed thirty degrees north over many millennia.  The crustal shift would then lift up the lake itself sufficiently to effect the broad swift emptying that in fact took place.

It may actually solve a problem.  You will observe that there are no large lakes positioned on the ice caps anywhere today.  It is not unreasonable at all to presume that they are simply impossible because natural elasticity and failure modes assure us such water will penetrate the ice and escape.

Therefore Lake Agassiz was bounded by land and perhaps even at sea level while trapped against the polar ice cap.  The move south lifted this water hundreds of feet higher and possibly even forced large amounts of the water to be pushed out by collapsing ice.

It is also possible that the original conditions for Lake Agassiz were set up by a prior shift in the crust and this final shift merely emptied the lake.  The possibility of an earlier shift is creditable because the last shift was clearly engineered and that would not be possible unless the engineers had first hand confirmation of the possibility.

We are still a long ways from working out time lines with any particular confidence of say even a century or so.  It really needs a round table with specialists.



Mega-flood triggered Europe's last big freeze... and global warming could plunge us into the cold again, warn scientists


Last updated at 2:00 AM on 02nd April 2010


Europe was plunged into a mini ice age 13,000 years ago after global warming  caused a mega-flood, geologists said today. 

Mark Bateman from the University of Sheffield, said a catastrophic flood was caused when an ice sheet in the U.S melted causing a huge amount of freshwater to be dumped into the Arctic Ocean.

This led to the shutting down of the Gulf Stream ocean circulation pattern that brings warmth to Europe.

A huge lake (pictured), the size of the UK, dumped fresh water into the Arctic Ocean around 13,000 years ago

'We're talking about a lake the size of the UK emptying very quickly,' Dr Bateman said.
'We don't know the exact period of time but we're talking about a catastrophic flood.'

The finding has confirmed past theories about the likely cause of a sudden cooling period called the Younger Dryas when temperatures in Europe, similar to today, quickly returned to ice age conditions. The cooling lasted for about 1,400 years.

'Our research shows that if you put a large volume of fresh water into the North Atlantic in a very short space of time, this is what happens,' Dr Bateman said.

His team's work is published in the latest issue of the journal Nature.

The Gulf Stream acts like a conveyer belt by bringing warm water from the tropics to Europe while cold salty water sinks to the depths in the far north. This 'overturning' circulation draws in yet more warm water from the south.

The last of winter sea ice in Liverpool Bay and exposed cliff sediment at the MacKenzie Delta in Arctic Canada. Scientists fear global warming could cause another massive flood leading to a big freeze

Climate scientists fear rapid global warming could trigger a sharp increase in the amount of meltwater from Greenland.

This surge in freshwater could trigger a tipping point that overwhelms the Gulf Stream, shutting it down and likely plunging Europe into another deep freeze.

Dr Bateman and his team confirmed the path of the floodwaters from Lake Agassiz that covered part of what is now Canada and the northern United States. The lake had formed in front of the ice-sheet that once covered a large part of North America.

Scientists had previously guessed that a giant flood unleashed from the lake probably caused the Younger Dryas cooling but couldn't confirm the route of the floodwaters.

A research team log sediments in a cliff exposure at Liverpool Bay, Northwest Territory, Arctic Canada. They said a massive flood caused the Gulf Stream to shut down 13,000 years ago.

Dr Bateman found that the waters flowed down the Mackenzie River, Canada's longest, rather than the Saint Lawrence Seaway that had previously seemed the most likely route.
Studying sediments from cliff sections along the river delta, he said the evidence spanned a large area at many altitudes. This could only be explained by a mega-flood from Lake Agassiz.

Dating of the sediments helped the team pin down the date of the flooding, showing that it occurred right at the start of the Younger Dryas.

Satellite observations and computer models by scientists have shown that the Greenland ice sheet is melting at an accelerating rate, dumping large amounts of ice and meltwater into the North Atlantic.

A study published in the journal Science last November said recent summers further accelerated Greenland's mass loss to the equivalent of 273 cubic kilometers of water per year in the period 2006-2008.


Read more: 

http://www.dailymail.co.uk/sciencetech/article-1262750/Mega-flood-triggered-Europes-big-freeze--global-warming-plunge-cold-warn-scientists.html#ixzz0k7cfmjkv

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