Skip to comments.Fingerprint of ancient abrupt climate change found in Arctic [Younger Dryas]
Posted on 07/15/2018 11:22:34 PM PDT by SunkenCiv
A research team led by Woods Hole Oceanographic Institution (WHOI) found the fingerprint of a massive flood of fresh water in the western Arctic, thought to be the cause of an ancient cold snap that began around 13,000 years ago... The cause of the cooling event, which is named after a flower (Dryas octopetala) that flourished in the cold conditions in Europe throughout the time, has remained a mystery and a source of debate for decades. Many researchers believed the source was a huge influx of freshwater from melting ice sheets and glaciers that gushed into the North Atlantic... However, geologic evidence tracing its exact path had been lacking. In 2013... aboard the U.S. Coast Guard Cutter Healy, the team gathered sediment cores from along the continental slope east of the Mackenzie River. After analyzing the shells of fossil plankton found in the sediment cores, they found the long sought-after geochemical signal from the flood. "The signature of oxygen isotopes recorded in foraminifera shells preserved in the sediment allowed us to fingerprint the source of the glacial lake discharge down the MacKenzie River 13,000 years ago," said co-principal investigator Neal Driscoll, a professor of geology and geophysics at Scripps Oceanography. "Radiocarbon dating on the shells provided the age constraints. Circulation models for the Arctic Ocean reveal that low-salinity surface water is efficiently transported to the North Atlantic. How exciting it is when the pieces of a more than 100-year puzzle come together."
(Excerpt) Read more at phys.org ...
In 2013, a team of researchers set sail to the eastern Beaufort Sea in search of evidence for the flood near where the Mackenzie River enters the Arctic Ocean, forming the border between Canada's Yukon and Northwest territories. From aboard the US Coast Guard Cutter Healy in ice-covered waters, the team gathered sediment cores from along the continental slope east of the Mackenzie River. Above, the piston corer is shown in horizontal position, with the gravity corer hanging vertically ready to be launched. Credit: Lloyd Keigwin, Woods Hole Oceanographic Institution
The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
Younger Dryas keyword, sorted:
Now the Dems will blame it on Trump! A guy can’t win, can he? Oh wait, that’s all he’s been doing.
Guess then that they will have to blame it on Bush.
So seldom do I, if ever, read mention of our Sun and our Suns role in our planets climate. Has this been your experience also, Civ or have I been reading the wrong material ?
There's no question that the Sun can cause ice to melt, and when the meltwater accumulated behind a wall of ice, the result when the ice dam gave way was like the massive runoff that formed the Channeled Scablands..
Not win? He's won more times since he announced his candidacy than I've won in my entire life! :^)
The problem with how this is presented is that the last BIG drop in temps was not 13,000 years ago, it started over 100,000 years ago. That “sharp” decline appears to have taken around 10k years, and then after that it gradually (with some fluctuations including the cold snap discussed in the article) got even colder, until it finally warmed fairly rapidly to approx. current temps (the beginning of our current ~11,700 yr. old interglacial period.)
In other words, the flood occurred during what was already a vicious and long period of glaciation that almost did in humans — but also likely helped forge us. A brief warm spell likely triggered the flood, melting huge quantities of Canadian glaciers, but at present there simply isn’t enough ice in Canada (even in winter) to cause a repeat performance. I somewhat doubt that at present such an occurrence (a sudden release of huge quantities of fresh water) could similarly encore anywhere in the Northern Hemisphere, except maybe in Greenland — but I suspect Greenland would drain more gradually and “evenly”. Antarctica might be a different story, but I know of no evidence to support that. (Ok, I don’t claim to know “everything”!!!) :-)
The last drop in temps was indeed sudden and recent, and is called the Younger Dryas.
As you point out, the conditions have never become like the glaciation since those long-ago times, and nothing we can do would have such drastic impact.
Yes, but Younger Dryas was really only a blip at the end of the already long and very cold period I described.* It's barely visible on the 450k yr. graphs, and doesn't compare (except in suddenness) to the big drops after most interglacial periods.
*I may have been "off" slightly -- looking more closely at more graphs, it appears to me that Younger Dryas may have occurred as temps were recovering, but not fully recovered, from the minimum of the last glacial. This makes sense: It suggests even more (2 or more miles deep) long-frozen Canadian ice melting than I'd thought! But either way, it's a "blip" in the overall trend / pattern.
Change the time scale by a factor of about 400k and YD may be roughly (very roughly) analogous to a cold snap following a few warmer days in (around here) early March.
Agreed mostly on the rest of your comment, but a large scale nuclear war might do it ("nuclear winter") -- different mechanisms, though...
The mainstream media does not carry much from the solar scientists. You have to seek out the information. The problem is that by simply reporting facts, the solar scientists totally refute greenhouse gas climate change by being totally accurate in predicting climate change based on solar activity.
What they have learned over the last 50 years about the makeup and behavior of the sun has allowed them to predict near term climate and weather cycles and based on the accuracy of those predictions, explain past events and cycles.
They are not the friend of the global warming crowd because they are actually predicting a cooling cycle over the next 30 to 50 years.
The world was warming, and the Younger Dryas was a sudden cooling event, and that’s all that’s being discussed in the article.
We know the magnetic poles switch every so often. It’s logical to assume the climate is affected by that switch. I blame any current climate change on the current movement of the magnetic North Pole.
My understanding of the impact of the Younger Dryas is that the prior warming had led to greater northern reach of flora and fauna, extending the human bounty northward into Eurasia whose populations subsequently increased.
The sudden cooling of the Younger Dryas forced a concentration of these humans and their food supplies into the mid-east latitudes, still plentiful, resulting in settlement and, next, farming.
Am I at least treading water here?
It must have been disruptive, at least, but there was still a lot of glacial cover over higher latitudes and altitudes.
The original Brexit?
Heh... there’s at least one really nice documentary about the separation event.
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