Researchers from the Woods Hole Oceanographic Institution have found evidence in the Western Arctic of a massive flood of fresh water believed to have been the cause of an abrupt cold snap that began around 13 kya. This abrupt climate change is known as the Younger Dryas which is believed to have ended 1000 years of global warming.
Just what brought about the Younger Dryas has been an issue for debate and speculation with most scientists believing it was brought about by a sudden influx of huge amounts of freshwater from melting ice sheets and glaciers. This fresh water rushed into the Atlantic and disrupted the deep water circulation system that moves warm water and releases heat into the atmosphere. Unfortunately, geologic evidence for this has been lacking.
Evidence of such a flood was undertaken near where the MacKenzie River enters the Arctic Ocean forming the border between Canada’s Yukon and Northwest Territories. Sediment cores were gathered along the continental slope east of the river. Analyzing these core samples the team evidence of a huge freshwater flood dating to about 13 kya.
I might also note that earlier this year researchers from the University College London and the Woods Hole Oceanographic Institution also found evidence that the North Atlantic ocean circulation has NOT been running at peak performance since the 1800s!! It is currently at its weakest point in the past 1600 years, in fact. If the circulation continues to weaken it could have even more significant impacts on weather in Europe and the US and even into Africa! A slowing of this circulation pattern is also believed to have brought about what is commonly called the “Little Ice Age” which lasted from around 1300 AD to about 1860 AD or simply for about 500 years!!