Our directory of things of interest

The river stolen by climate change

The sudden retreat of the Kaskawulsh glacier has caused the water flowing into the Slims River to dramatically recede The sudden retreat of the Kaskawulsh glacier has caused the water flowing into the Slims River to dramatically recede Tomas Kulaja
03 Jun
What impact could an unprecedented incident of ‘river piracy’ have on Canada’s Yukon territory?

When Jim Best and Dan Shugar visited the Slims River in Canada’s Yukon last summer, they made a discovery that caused the world to sit up and pay attention to this remote corner of North America. Instead of a flowing current, the pair found only a dry and dusty river bed. ‘The river had virtually dried up, and the lake into which the river flowed had dropped in water level,’ recalls Best, Professor of Sedimentary Geology at the University of Illinois.

They later discovered that the water had rerouted into a different river system – a phenomenon with the somewhat dramatic name of ‘river piracy’. Instead of flowing along the Slims river, through Kluane Lake, and eventually out into the Bering Sea, the water now travels primarily along the Kaskawulsh river, then south into the Alsek river, and ultimately into the Pacific Ocean.

Such a transformation has occurred numerous times throughout the planet’s geological history – often due to gradual erosion or the movement of a fault – but has never been observed to occur as suddenly, happening over just a few days in May 2016. ‘Geologists have seen [evidence of] river piracy before, but nobody to our knowledge has documented it actually happening [within] our lifetimes,’ explains Shugar, Assistant Professor of Geoscience at the University of Washington, Tacoma.

The dramatic switch was caused by the rapid retreat of the Kaskawulsh glacier – thanks to climate change – which caused the flow of the meltwater to be redirected, and prompts questions about the impact it could have on the surrounding Yukon territory. Best points out that while much of the southern part of the territory is ‘sparsely populated’, and therefore potential flooding caused by the extra water is unlikely to cause any ‘real human impacts’, the opposite issue could be a cause for concern further north.

‘If Kluane Lake levels go down,’ he predicts, ‘the lake could thus have no inflow and no exit flow, which would radically alter lake water nutrients and circulation, and this may impact on the lacustrine ecology. In addition, if the lake outlet were to dry up as a consequence, this river would be dry or far lower and thus the few habitations along it would be affected.’

This was published in the June 2017 edition of Geographical magazine.

Related items

Geographical Week

Get the best of Geographical delivered straight to your inbox every Friday.

Subscribe Today

Adventure Canada


Aberystwyth University University of Greenwich The University of Winchester




Travel the Unknown


Like longer reads? Try our in-depth dossiers that provide a comprehensive view of each topic

  • National Clean Air Day
    For National Clean Air Day, Geographical brings together stories about air pollution and the kind of solutions needed to tackle it ...
    The Air That We Breathe
    Cities the world over are struggling to improve air quality as scandals surrounding diesel car emissions come to light and the huge health costs of po...
    Diabetes: The World at Risk
    Diabetes is often thought of as a ‘western’ problem, one linked to the developed world’s overindulgence in fatty foods and chronic lack of physi...
    The Nuclear Power Struggle
    The UK appears to be embracing nuclear, a huge U-turn on government policy from just two years ago. Yet this seems to be going against the grain globa...
    Hung out to dry
    Wetlands are vital storehouses of biodiversity and important bulwarks against the effects of climate change, while also providing livelihoods for mill...


NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in PLACES...


IPCC Cities and Climate Change Conference: Alberta host dresses non-renewable…


Increased carbon dioxide is affecting freshwater ecosystems


The latest laser scanning technology reveals new insights into the…


Deforestation is having an unexpected effect in the Amazon: fewer…


The iconic Douglas fir tree, familiar to fans of the…


Rocky Mountain forests are not regenerating after wildfires


Cape Town is edging closer to ‘Day Zero’, the long-feared…


Ongoing restoration projects are breathing new life into Florida’s Everglades


Despite protests, an experimental pedestrianisation system is proving to be…


National Archives map historian, Rose Mitchell, highlights some of the…


An expedition into the Jordanian desert is helping teachers and…


Trivia fans take note, Mount Hope in the British Antarctic…


An enormous hydropower development in Ethiopia is expected to put…


From nuclear warnings to whether your favourite band will ‘make…


New maps of global reptile distribution reveal significant gaps in…


Indigenous conservation schemes in Peru can be more effective than…


How are the EU member nations faring in the fight…


Violence against women violates human rights, and the lack of…


Deadly heat waves could become more frequent in cities thanks…


These 13 poignant infographics are in the running for the…