An entire river just disappeared in Canada, and it took only a few days for it to vanish.
It was known as the Slims River, and although it no longer exists, it probably won’t be forgotten anytime soon, as it bears the dubious distinction of being the first river to vanish completely due to climate change.
To be clear, the Slims didn’t just evaporate. It changed course in such a way that its flow was subsumed entirely by another nearby waterway called the Kaskawulsh River. And Slims wasn’t just some insignificant stream: its average width was almost 500 meters.
This phenomenon — of one river absorbing or capturing the flow of another river — is well-known to geologists, who refer to it as “river piracy“. But it’s a phenomenon that usually plays out over centuries or millennia, not days. Which is why the near-instantaneous piracy of the Slims has scientists sounding the alarm.
To see how this ties in with climate change, look at the source of the erstwhile Slims: the meltwater runoff of the Kaskawulsh Glacier, a glacier which has been melting at a much higher rate thanks to increased temperatures resulting from anthropogenic climate change.
It seems the increased melting fed so much water into the Slims River that it burst its banks, but not by way of flooding. Instead, it was able to punch an entirely new channel in the ice, diverting its course entirely, and feeding into the Kaskawulsh River.
This change is likely to be permanent, scientists say.
To get an idea of what has been lost, take a look at this footage which shows the Rivers Slims and its surrounding area just a few years ago, an area that will now become unrecognisable and barren without its supply of fresh water:
This raises some serious questions about the stability of rivers globally. When looked at as water resources for human populations, rivers are generally stable and reliable, aside from natural flooding, droughts, or major man-made diversions resulting from dams.
Thankfully, no large human population was relying on the Slims for food, shipping, energy, or drinking water. But imagine how all of those would be affected for any city unlucky enough to be built on a river that suddenly disappears due to river piracy.
Once again, nature reminds us that we are running headlong into unpredictable territory. And as man-made climate change shows no signs of slowing down, let’s all hope “river piracy” doesn’t become part of our everyday language.