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  • Geoscientists spend their lives studying features in nature that move very, very slowly.

  • Glacial melt, plate tectonics, things like these take their sweet time to develop.

  • So, when an entire river vanishes in just four days, it's safe to assume geoscientists

  • are going to freak out.

  • A paper recently published in Nature called this very sudden disappearing actriver

  • piracy.”

  • Sadly, there were no actual pirates involved in the making of this studybut river

  • piracy, or it's less exciting name, “stream capture”, is a geomorphic phenomenon where

  • one river captures and redirects the flow of another.

  • In 2015, a team of scientists observed that the Slims River in the Yukon was [quote] "swift,

  • cold and deep," flowing from one of Canada's largest glaciers north to the Bering Strait.

  • Luckily for us, NASA was watching.

  • Check this out.

  • In 2015, a team of scientists observed that the Slims River in the Yukon was [quote] "swift,

  • cold and deep," flowing from one of Canada's largest glaciers north to the Bering Strait.

  • Then in 2016 they came back and the river was completely different.

  • Its waterflow was at a near screeching halt.

  • THEN in 2016 NASA took this picture.

  • The scientists on the ground came back and the river was completely different.

  • Its waterflow was at a near screeching halt.

  • It looked more like “a long, skinny lake,” and they could see the water level dropping

  • by the day.

  • What had happened was, a tall canyon had formed at the end of the nearby glacier,

  • rerouting melt water from the Slims to the Kaskawulsh River, joining the Alsek River

  • south.

  • Basically, the Slims river was stolen by another river, and it just completely changed course!

  • This shift is affecting fish populations, wildlife, lake chemistry in the area, even

  • sheep are changing their grazing patterns.

  • Which all sounds kind of meh.

  • BUT.

  • Think about how this could affect everything else!

  • Land degradation and lack of freshwater will impact billions of people globally.

  • Plus, there may be more consequences that we haven't even thought of yet!

  • This is the first time in modern history that scientists have actually seen a river do this.

  • A whole river was going north, now it's going south!

  • That's huge.

  • And why?

  • Of course you already know.

  • Man-made climate change.

  • But not global warming as a whole, instead, one of its many facets: glacial retreat.

  • Glaciers are these massive bodies of snow and ice that change in response to temperature

  • and precipitation.

  • When a glacier starts to retreat due to high temperature or less snowfall, glacial melt

  • will outpace new accumulation of snow and ice.

  • This affects the availability of fresh water for animals, plantseven humans!

  • This connects to the river piracy in the Yukon, because the massive Canadian glacier that

  • fed the Slims River is in retreat, thanks to a cold period centuries ago called the

  • Little Ice Age and warming due to greenhouse gases.

  • Now while this study was just one glacier and we shouldn't generalize too much, glacial

  • retreat is a worldwide phenomenon.

  • Glaciers in the Himalayas, Andes, Alps, and Rockies are all backpedaling at greater speeds

  • in response to our globe's changing climate.

  • Of course, glacial melt is happening in some of the farthest corners of our planet and

  • only a small number of communities are directly affected, for now.

  • So, while global warming is a multi-century process; things can happen quickly

  • Consequences of global warming and climate change are being seen now.

  • And huge parts of the environment can change course in just a matter of days

  • And no one knows what this will mean for the future

  • So if all these glaciers keep retreating, what happens if all the world's ice melts?

  • Check out this video here to learn more about that.

  • What's your favourite piece of evidence that climate change is happening?

  • Let us know in the comments, like this video, and subscribe!

Geoscientists spend their lives studying features in nature that move very, very slowly.

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B2 US river glacial glacier retreat melt warming

When a River Goes Missing, It's Kind of a Big Deal...

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    joey joey posted on 2021/04/14
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