#KaskawulshGlacier, #Yukon, #SlimsRiver, #BeringSea, #KaskawulshRiver, #GulfOfAlaska, #PacificOcean, #DanShugar, #University of Washington, #Haines Junction #JamesBest, #USA, #Nature Geoscience, #University Of Illinois, #Kluane National Park and Reserve
Dan Shugar, a geoscientist at the University of Washington Tacoma and lead author of a study published on April 17 in the journal Nature Geoscience, and his team were able to document the retreat of Kaskawulsh Glacier, one of Canada’s largest glaciers, abruptly and radically altering the regional drainage pattern in spring 2016, media reports said.
This magnitude of retreat, reported by scientists, which suddenly switched direction had not been documented before in modern times, CBCNews reports said.
"Climate change is happening, is affecting us and it's not just about far-off islands in the South Pacific. It's not just about sea-level rise for them, said Shugar, and added, "The effects can be very rapid and can be somewhat unanticipated," CBCNews reports said
This geologic phenomenon, also known as stream capture or river piracy, pointed to a direction where a stream or river is diverted toward another body of water caused usually by a landslide or glacial dam collapse.
"This was the first event we could find where river piracy occurred right under our noses and due to contemporary climate change," said Shugar, CBCNews reports said.
Previous cases of river piracy may have taken place thousands of years ago or more, said Shugar in an interview with CBC News.
Shugar and his team of scientists had stumbled upon this change last summer by accident when Shugar and colleague James Best, a professor of geology and geography from the University of Illinois, travelled to the Slims River in the Kluane National Park and Reserve west of Haines Junction, Yukon.
"We went there anticipating low flow and it turned out to be no flow," said Shugar, CBCNews reports said.
Both Best and Shugar were taken aback by this change. Instead of seeing blue, shimmering shallow water, they could see only exposed and dried sediments which turned into a huge dust storm due to blowing of strong winds.
The group decided to research further with a mapping drone to help survey the area and discovered that previously glacier had melted into two ponds and flowed into the Slims and had carved a new 30-metre canyon through the glacier towards a lower elevation.
As a result of the glacier retreating about 1.6 kilometres over the past 100 years, the meltwater had now found a steeper gradient down to one river instead of the other, said Best.
Although their colleague and co-author John Clague had guessed in a 2006 study that the Slims River would eventually disappear, they did not predict the timeframe.
River gauges showed there was an abrupt drop in the water level in just four days between May 26 and May 29, 2016.
Best said that witnessing this phenomenon provided them with a very good opportunity for research that has implications and long-lived potential effects, not only on the landscape but everything that inhabits and lives on and in the landscape.
(Reporting by Asha Bajaj)
Image of River Piracy: Courtesy of The Daily Star