Retreating Yukon glacier makes river disappear
A valley of mud and dust where Slims River used to flow into Kluane Lake
It's been the main source of water into Yukon'sKluaneLake for centuries, but now the Slims River has suddenly slimmed down to nothing.
"What folks have noticed this spring is that it's essentially dried up," said Jeff Bond of the Yukon Geological Survey.
"That's the first time that's happened, as far as we know, in the last 350 years."
What's happened is some basicglacier hydrology,Bond says essentially, the KaskawulshGlacierhas retreated to the point where its melt water is now going in a completely different direction, away from the Slims Valley.
Instead of flowing north 19 kilometresfrom the glacier's toeinto KluaneLake (and ultimately, the Bering Sea), that melt water is now drainingeastward viathe Kaskawulsh River towards the Pacific Ocean off the Alaska panhandle.
It's a reminder that glacier-causedchange is not always glacial-paced.Last year, the Slims River was still a potentially dangerous waterway, now the area ismore prone to dust storms.
"It's certainly not unusual to see rapid drainage changes in and around these glaciers. It's a common situation," Bond said.
"Until vegetationreallystarts to stabilize that floodplain, it's going to be a dusty place, I'd imagine ...It will be a really interesting study to see how that floodplain evolves in the next ten years or so."
KluaneLakewaterlevelexpected to drop
It's possible the Slims River was only ever just a temporary variance in the landscape a 300-oddyear hydrological whim.
Scientists say itonly began flowing aroundthe year 1700, when the so-called "Little Ice Age" caused the Kaskawulshglacier to advance, and then divert most of its melt water from the KaskawulshRiverto the Slims Valley.
As a result, KluaneLake grew.
Now, with the Slims River gone, hydrologists are expecting the lake level todrop.
"How much that lowers kind of depends on the outlet, the depth of the water at the outlet right now.I'm predicting it could be at least a meter," Bond said.
With files from Vic Istchenko