The authors compared death records and temperature data in Canada, Estonia, Germany, Latvia, Finland, Russia, Sweden, Italy, Japan, and the northern United States. They analyzed about 4,000 records in total over a 26-year period, although the time period varies depending on the data available in each country.
Researchers have found that more cold-weather drownings occur in the spring, when daily low temperatures rise too much to support stable ice structures. At the same time, these warmer temperatures make it more pleasant to spend time outdoors, meaning more people are spending time on the ice.
Northern Canada and Alaska have higher drowning rates, even in very cold weather. Dr Sharma says it‘s probably because people there are just spending more time on the ice. Indigenous communities near the Arctic depend on waterways for food and transport, which means more time on the ice in winter and an increased risk of drowning.
The coronavirus pandemic could also put more people at risk.
“If this winter looks anything like this summer,” said Dr. Sharma, “a lot of people have spent time in cabins in Ontario because we can’t go anywhere.
She said ice with standing water, slush or holes in the surface was generally dangerous. “Snow cover is when it gets tough,” said Dr Sharma. “People think there is so much snow on the ice that the ice must be thick,” but snow can also act as insulation, causing the ice to melt faster.
“We, as individuals, need to adapt our decision-making,” she added, and focus on how changing winters affect local rivers, lakes and streams. “It may not be as safe today as it was 30 or 40 years ago.”