At first it looks like a terrible idea, but it doesn't take long to realize that this is pure joy captured on video.
The clip was filmed in late November by Jonas Landmark and Karin Bäckborns on Lake Blanktjärn in central Sweden. Their dogs Trissa and Vilma tagged along too.
While the ice is actually around 10 cm thick, it looks paper thin (you can actually see the fish swimming underneath their feet).
From the looks of things, this is an example of congelation ice, which can form on a freshwater lake that is mostly free of impurities. Stanford scientist Miles Traer recently explained to io9 that the ideal scenario for ice like this involves "a slow freeze, big ice crystals, close to no air bubbles and water devoid of dust and other particle impurities."
Landmark told the Weather Network that the lake doesn't usually look this but that the conditions were just "perfect."
"It was as being at an aquarium," he said.
So. Freaking. Cool.
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