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No one can ever say for sure what the future will bring, but this new video has summed up all the science-backed predictions that we can reasonably make about how Earth will change over the next 1 billion years. It’s highly unlikely that anyone will be around to see most of these changes come to pass, so consider this an exclusive front-row seat to a world where supercontinents reign supreme, Mount Everest is no longer the tallest mountain on our planet, Earth enters another glacial period regardless of current global warming trends. and then the Sun becomes a lot hotter. Just another reason we should be glad we live at the time we do. Reposted from Science Alert and RealLifeLore

An ancient flood seems to have stalled the circulation of the oceans, plunging the Northern Hemisphere into a millennium of near-glacial conditions. Thirteen thousand years ago, an ice age was ending, the Earth was warming, the oceans were rising. Then something strange happened – the Northern Hemisphere suddenly became much colder, and stayed that way for more than a thousand years. For some time, scientists have been debating how this major climatic event – called the “Younger Dryas” – happened. The question has grown more urgent: Its answer may involve the kind of fast-moving climate event that could occur again. This week, a scientific team made a new claim to having found that answer. On the basis of measurements taken off the northern coasts of Alaska and Canada in the Beaufort Sea, the scientists say they detected the signature of a huge glacial flood event that occurred around the same time. This flood, they posit, would have flowed from the Arctic into the Atlantic Ocean and shut down the crucial circulation known as the “Atlantic meridional overturning circulation” (or AMOC) – plunging Europe and much of North America back into cold conditions. “Even though we were in an overall warming period, this freshwater, exported from the Arctic, slowed down the vigor, efficiency of the meridional overturning, and potentially caused the cooling observed strongly in Europe,” said Neal Driscoll, one of the study’s authors and a professor at the Scripps Institution of Oceanography. The work, published in Nature Geoscience, was led by Lloyd Keigwin of the Woods Hole Oceanographic Institution along with researchers at that institution, Scripps and Oregon State University. The result remains contested, though, with other researchers still arguing for different theories of what caused the Younger Dryas – including a very differently routed flood event that would have entered the ocean thousands of miles away. Nonetheless, the story is relevant because today, we’re watching another – or rather, a further – deglaciation, as humans cause a warming of the planet. There is also evidence that the Atlantic circulation is weakening again, although scientists certainly do not think a total shut-off is imminent, and are still debating the causes of what is being observed. Either way, the new research underscores that as the Earth warms and its ice melts, major changes can happen in the oceans. And could happen again. The researchers behind the current study, working on board the U.S. Coast Guard Cutter Healy, analyzed sediments of deep ocean mud, which contain the shells of long-dead marine organisms called foraminifera. In those shells, the scientists detected a long-sought-after anomaly recorded in the language of oxygen atoms. The shells contained a disproportionate volume of oxygen−16, a lighter form (or isotope) of the element that is found in high levels in glaciers. That is because oxygen−16, containing two fewer neutrons and therefore lighter than oxygen−18, evaporates more easily from the ocean but does not rain out again as readily. As a result, it often falls as snow at high latitudes and is stored in large bodies of ice. “This is the smoking gun for fingerprinting glacial lake outbursts,” Driscoll said. And that means the findings may also represent the trigger for the Younger Dryas. The thinking is that as the ice age ended and the enormous Laurentide ice sheet atop North America began to retreat, the resulting meltwater fed a bevy of large lakes atop the depressed surface of the continent. That included the massive glacial Lake Agassiz, which stretched from the Great Lakes northwestward across much of Canada. The approximate maximum extents of major glacial lakes that formed from the retreat of the western Laurentide Ice Sheet. (Shannon Klotsko, Scripps Institution of Oceanography, University of California at San Diego) Prior research had shown that for a while, much of the resulting freshwater drained down the Mississippi River and into the Gulf of Mexico. But at some point, as the ice sheet continued to shrink, the flow of water appears to have been suddenly rerouted to the north or to the east, where it could do more potential damage to the ocean circulation in the Atlantic. There has long been scientific debate about where all the meltwater actually entered the ocean, though – with some contending that it would have occurred through the St. Lawrence River, which flows past today’s Montreal and Quebec City and thus out into the Atlantic. The new research holds that, instead, the floodwater exited through the Mackenzie River, which stretches across today’s Northwest Territories, emptying straight into the Arctic Ocean. It would certainly have been an enormous flow of fresh water. “I would say somewhere between the Mississippi and the Amazon,” Keigwin said. That could have interfered with the Atlantic circulation, which is crucial because it carries warm water northward, and so heats higher latitudes. Eventually, the waters of the circulation become very cold as they travel northward, but because they are also quite salty, they sink because of their high density and travel back south again. Freshening is therefore the Achilles’ heel of the circulation. And the new study argues that although the glacial water would have entered the seas very far away near the present Alaska-Canada border, it would have then circulated around the Arctic, eventually traveling south past Greenland and entering the key regions that are crucial to the overturning circulation, which tend to be off Greenland’s southern coasts. Not everyone is convinced, though – including some researchers who have previously published results suggesting that the outburst flood or flow was instead to the east, through the St. Lawrence River. “They have produced a nice signal of the release of freshwater into the Arctic Ocean, but the conclusions are based on an uncertain chronology which, when trying to tie together events so closely, requires some independent confirmation,” Peter Clark, an Oregon State University geoscientist who has published evidence supporting the St. Lawrence River theory, said in an email. Anders Carlson, Clark’s co-author and colleague at Oregon State University, sent a geological study finding that, as he put

A recent Smithsonian Magazine article gives some interesting insights to present-day Jökulhlaups (glacial outburst floods) that are but minuscule relatives of the cataclysmic Ice Age Floods. Iceberg Lake was on the edge of a western tributary of the Tana Glacier, but in 1999 the lake suddenly vanished. Dammed on its southern end by ice, the water, with persistently warming temperatures, had bored a hole under the ice and escaped through tunnels to emerge ten miles away and empty into the Tana River. The sudden drainage of a glacier-dammed lake is not uncommon. “Some lakes in Wrangell-St. Elias regularly drain,” Loso said. Hidden Creek Lake, for instance, near McCarthy, drains every summer, pouring millions of gallons through channels in the Kennicott Glacier. The water gushes out the terminus of the Kennicott, causing the Kennicott River to flood, an event called a jokulhlaup—an Icelandic word for a glacial-lake outburst flood. “The Hidden Creek jokulhlaup is so reliable,” said Loso, “it has become one of the biggest parties in McCarthy.” But the disappearance of Iceberg Lake was different, and unexpected. It left an immense trench in the ground, the ghost of a lake, and it never filled up again. The roughly six-square-mile mudhole turned out to be a glaciological gold mine. The mud, in scientific terms, was laminated lacustrine sediment. Each layer represented one year of accumulation: coarse sands and silts, caused by high runoff during the summer months, sandwiched over fine-grained clay that settled during the long winter months when the lake was covered in ice. The mud laminations, called varves, look like tree rings. Using radiocarbon dating, Loso and his colleagues determined that Iceberg Lake existed continuously for over 1,500 years, from at least A.D. 442 to 1998. “In the fifth century the planet was colder than it is today,” Loso said, “hence the summer melt was minimal and the varves were correspondingly thin.” The varves were thicker during warmer periods, for instance from A.D. 1000 to 1250, which is called the Medieval Warming Period by climatologists. Between 1500 and 1850, during the little ice age, the varves were again thinner—less heat means less runoff and thus less lacustrine deposition. “The varves at Iceberg Lake tell us a very important story,” Loso said. “They’re an archival record that proves there was no catastrophic lake drainage, no jokulhlaup, even during the Medieval Warming Period.” In a scientific paper about the disappearance of Iceberg Lake, Loso was even more emphatic: “Twentieth-century warming is more intense, and accompanied by more extensive glacier retreat, than the Medieval Warming Period or any other time in the last 1,500 years.” Loso scratched his grizzled face. “When Iceberg Lake vanished, it was a big shock. It was a threshold event, not incremental, but sudden. That’s nature at a tipping point.” One of the most startling, and devastating, consequences of this rapid melting of the ice was the Icy Bay landslide. The Tyndall Glacier, on the southern coast of Alaska, has been retreating so quickly that it is leaving behind steep, unsupported walls of rock and dirt. On October 17, 2015, the largest landslide in North America in 38 years crashed down in the Taan Fjord. The landslide was so enormous it was detected by seismologists at Columbia University in New York. Over 200 million tons of rock slid into the Taan Fjord in about 60 seconds. This, in turn, created a tsunami that was initially 630 feet high and roared down the fjord, obliterating virtually everything in its path even as it diminished to some 50 feet after ten miles. “Alder trees 500 feet up the hillsides were ripped away,” Anderson says. “Glacial ice is buttressing the mountainsides in Alaska, and when this ice retreats, there is a good chance for catastrophic landslides.” In other ranges, such as the Alps and the Himalaya, he says, the melting of “ground ice,” which sort of glues rock masses to mountainsides, can release enormous landslides into populated valleys, with devastating consequences. “For most humans, climate change is an abstraction,” Loso says when I meet him in his office, which is down a long, dark, heavily beamed mine building in Kennecott. “It’s moving so slowly as to be basically imperceptible. But not here! Here glaciers tell the story. They’re like the world’s giant, centuries-old thermometers.” Read the entire article “A Daring Journey Into the Big Unknown of America’s Largest National Park” online at SmithsonianMag.com