19/04/2017 12:34 AM AEST | Updated 19/04/2017 1:19 AM AEST

Canada's Slims River Disappeared In Just Four Days

This is unprecedented.

A vast river vanished in just four days after the glacier it flowed from retreated due to climate change.

The Slims River in Canda is the first in modern history to have disappeared at such a speed, according to scientists who observed the process.

Normally, it takes thousands of years for a river to expire, as tectonic forces, natural damning or erosion reroute the water into a different path.

But at the end of May 2016, the Kaskawulsh Glacier retreated so far that its meltwater was diverted into another river in an event described by researchers as “geologically instantaneous”, according to Science Alert.

Dan Shugar/University of Washington Tacoma
Photo shows the meltwater stream along the toe of Kaskawulsh Glacier seen on the left that is diverting fresh water from one river to the other.

“Geologists have seen river piracy, but nobody to our knowledge has documented it happening in our lifetimes,” lead author Dan Shugar, a geoscientist at the University of Washington Tacoma, said in a statement.

“People had looked at the geological record — thousands or millions of years ago — not the 21st century, where it’s happening under our noses.”

As a result of the event, glacial meltwater that for hundreds of years ran into the Bering Sea will now end up in the Pacific.

The redistribution has already taken its toll on both regions’ ecosystems, with disruptions to lake chemistry, fish populations and the behaviour of wildlife reported.

Jim Best/University of Illinois

Researchers said the act of river piracy highlighted the power of climate change to redraw landscapes.

John Clague, a co-author of the study, said: “[This] event is a bit idiosyncratic, given the peculiar geographic situation in which it happened, but in a broader sense it highlights the huge changes that glaciers are undergoing around the world due to climate change.”