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Related: About this forumCatastrophic failure of ice age dam changed ocean circulation and climate
Catastrophic failure of ice age dam changed ocean circulation and climate
February 12, 2016
The catastrophic release of fresh water from a vast South American lake at the end of the last Ice Age was significant enough to change circulation in the Pacific Ocean, according to new research co-authored by a PhD student from the University of Bristol.
"This study is important because we are currently concerned about the volumes of fresh water entering the oceans from the melting ice sheets in Greenland and Antarctica and this gives us an indication of the likely effects," the study's lead author, Professor Neil Glasser from Aberystwyth University said.
The study, published today in Scientific Reports, reveals that the lake, which was about one third the size of Wales, drained several times between 13,000 and 8,000 years ago, with devastating consequences.
At its high point the lake extended over 7,400km2, held 1500km3 of water and occupied a basin which now contains Lago General Carrera in Chile and Lago Buenos Aires in Argentina.
Held back by a dam formed by a large ice sheet, the lake drained rapidly as the ice sheet shrank in size.
More:
http://phys.org/news/2016-02-catastrophic-failure-ice-age-ocean.html#jCp
HooptieWagon
(17,064 posts)Britain was a peninsula connected to Europe. Glacier melt created a large lake where North Sea currently is. Dammed by the glacier to the north, eventually the lake over-topped the isthmus, and flowed into the Atlantic, creating the English Channel.
Trajan
(19,089 posts)In the Pacific Northwest ... With Glacial Lake Missoula breaking down every few millennia and sending a half mile high wall of water careening through the terrain from Montana to the Pacific Ocean via The Columbia Gorge (this is how the gorge was created) ...
The Willamette Valley was a 'settling pond' for those glacial floods, and it is a bountiful farming area for that reason ...
GliderGuider
(21,088 posts)Similar time period, similar events.
https://en.wikipedia.org/wiki/Lake_Agassiz
Around 13,000 years ago, the lake came to cover much of Manitoba, northwestern Ontario, northern Minnesota, eastern North Dakota, and Saskatchewan. At its greatest extent, it may have covered as much as 440,000 km2 (170,000 sq mi), larger than any currently existing lake in the world (including the Caspian Sea) and approximately the size of the Black Sea
Lake Agassiz's major drainage reorganization events were of such magnitudes that they had significant impact on climate, sea level and possibly early human civilization. Major freshwater release into the Arctic Ocean is considered to disrupt oceanic circulation and cause temporary cooling. The draining of 13,000 years ago may be the cause of the Younger Dryas stadial.[1][8][9] The draining at 9,90010,000 years ago may be the cause of the 8,200 yr climate event. A recent study by Turney and Brown links the 8,500 years ago drainage to the expansion of agriculture from east to west across Europe; he suggests that this may also account for various flood myths of prehistoric cultures, including the Biblical flood narrative.[10]
NickB79
(19,258 posts)1100 km3 for Lake Michigan, 2900 km3 for Lake Superior.