Ice-skating, fishing and driving heavy trucks on frozen lakes could soon be activities of the past as a result of climate change, scientists have found.
There are greater than 58.5 million lakes on Earth covered by ice, either on a seasonal or year-round basis. Viewers of ‘Frozen Planet II’ have been treated to a few of these spellbinding vistas within the UK recently.
But while we’re well aware that the poles are melting at an alarming rate – with the Arctic warming 3 times faster than the remainder of the planet – less is thought in regards to the toll global heating is taking up the world’s frozen lakes.
People living by these icy bodies of water have witnessed a widespread lack of lake ice, with many experiencing delayed winter freezing or an earlier melt.
Now, using a sophisticated ‘lake simulator’, scientists have determined that seasonal lake ice can be 0.23 metres thinner on average by the tip of the century. Lakes will even be bare for 38 days more on average.
“Our results reveal that the [annual] duration of secure ice over the subsequent 80 years will shorten by two to 3 weeks depending on the longer term warming level,” says Dr Lei Huang, co-author of two recent studies on the subject published in Nature and Earth’s Future journals.
“In regions where lakes are used as ice roads to move heavy goods and supplies, the variety of days with secure ice conditions will decline by greater than 90 per cent, even for a moderate warming of 1.5°C above early twentieth century conditions.”
Lake communities are on thin ice
Seasonal ice is vital to many lake ecosystems and the individuals who depend upon them.
Northern Indigenous communities already suffer amongst the very best winter drowning rates through ice. There have been increasingly search and rescue incidents related to thinning ice cover in Alaska and Canada’s northern territories, where Indigenous people depend on traditional hunting and fishing for his or her livelihoods.
Within the Far North, roads over frozen lakes are used as critical transport routes for getting food, fuel, medical supplies and machinery to distant communities in winter – avoiding the necessity for expensive air travel. However the trucks need the ice to be at the very least one metre thick.
Without human intervention, the researchers estimate that the duration of secure ice for winter roads is projected to say no by as much as 99 per cent inside a 3°C warmer world.
Perched on the shore of Lake Superior, one among North America’s Great Lakes, the town of Bayfield, Wisconsin, also faces a less stable future. Currently, an ice road is used to move children to high school on Madeline Island, replacing the summer ferry, however the ice should be at the very least 30cm thick to make sure a secure crossing.
“In keeping with our computer model simulations, many densely populated regions within the mid-latitudes are projected to experience a big deterioration in secure ice conditions for recreational activities,” says Dr Iestyn Woolway from Bangor University within the UK.
“Already, a 1.5°C warming above early twentieth century conditions can result in greater than 60 per cent loss within the duration of secure lake ice. This may negatively impact local communities that depend on the ice recreation industry.”
In Sweden, the ice fishing industry alone generates €890 million in revenue annually. Though the researchers note that declining winter sums could possibly be offset with increasing income within the open-water summer season.
How are thinning lakes impacting the ecosystem and animals?
Just as people face more perilous journeys within the Far North, so animals have riskier crossings to make across frozen lakes and rivers.
Around 10,000 migratory caribou drowned within the Quebec-Labrador Peninsula within the Nineteen Eighties due to thin ice.
Global heating also threatens unique lake ecosystems which have adapted to recurring frozen lake conditions over tens of hundreds of years.
“Lake organisms are suffering severe changes of their habitat,” in accordance with the Nature study, meaning some cold species could turn into locally extinct in polar lakes.
This is occurring as scientists and explorers make recent discoveries about these unique ecosystems. Only a decade ago, divers found ancient, alien-like structures called giant stromatolites rising from the underside of Lake Untersee in East Antarctica. These primitive life-forms might point to the existence of life on other frozen planets, David Attenborough told viewers of his BBC show.
It’s still hard to say exactly how individual lakes can be impacted. “We have now to confess that our simulation can have larger uncertainties in [the Great Lakes] than in small lakes, because ice dynamics are more complicated in these large lakes, and we don’t consider the role of lake size within the ice decline in the present study,” Dr Huang tells Euronews Green.
In each Lake Superior and Russia’s Baikal Lake, he adds that lake ice loss is predicted to have large impacts on aquatic ecosystems due to altered nutrient cycling and lightweight availability. But, “the underlying dynamics and drivers remain to be uncovered.”