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For the First Time On Record, Human-Caused Climate Change Has Rerouted an Entire River (washingtonpost.com)
A team of scientists on Monday documented what they're describing as the first case of large-scale river reorganization as a result of human-caused climate change (Editor's note: could be paywalled; alternative source). From a report: They found that in mid-2016, the retreat of a very large glacier in Canada's Yukon territory led to the rerouting of its vast stream of meltwater from one river system to another -- cutting down flow to the Yukon's largest lake, and channeling freshwater to the Pacific Ocean south of Alaska, rather than to the Bering Sea. The researchers dubbed the reorganization an act of "rapid river piracy," saying that such events had often occurred in the Earth's geologic past, but never before, to their knowledge, as a sudden present-day event. They also called it "geologically instantaneous." "The river wasn't what we had seen a few years ago. It was a faded version of its former self," lead study author Daniel Shugar of the University of Washington at Tacoma said of the Slims River, which lost much of its flow because of the glacial change. "It was barely flowing at all. Literally, every day, we could see the water level dropping, we could see sandbars popping out in the river."
Addendum to my last:
Note that I live near the Mississippi River, which, until it was leveed all to hell-and-gone, routinely shifted its channel from year to year. So the notion of a river rerouting itself isn't terribly surprising to me, nor is it really that big a deal, unless it reroutes itself over someone's house or a town (which the Mississippi used to do from time to time in the 19th Century).
"I do not agree with what you say, but I will defend to the death your right to say it"
Note that I live near the Mississippi River, which, until it was leveed all to hell-and-gone, routinely shifted its channel from year to year. So the notion of a river rerouting itself isn't terribly surprising to me, nor is it really that big a deal, unless it reroutes itself over someone's house or a town (which the Mississippi used to do from time to time in the 19th Century).
Sure, but this is well known from rivers that run over a plain - they tend to meander, silt builds up etc. The effect is rather more dramatic when the source dries up or goes to another river. It is the same, basic processes that are behind, but whereas the meandering river phenomenon is common, the interesting thing about this case is that it can be attributed directly to climate change: the glacier has melted away to such a degree that it now drains away through an entirely different channel. It would be great if people would not be so dismissive about these things - the scientists that bring these things up don't do so in order to get high approval rating on social media; they aren't airheaded celebrities craving attention; they point out observations that they think are potentially important, and which they suggest you should have a look at. It may feel great saying stuff like 'Yeah, shit happens; so what?" - right until the day when shit happens to you, particularly if you could have done something about it if only you could have been bothered.