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A way of life in peril as inland lakes and rivers fail to freeze

A way of life in peril as inland lakes and rivers fail to freeze

York U expert can talk to the loss of freshwater ice and its impact on communities

TORONTO, Tuesday, Dec. 17, 2019 – Melting glaciers and rising sea levels receive a lot of attention, but there has been far less research on how a warmer world affects people who rely on freshwater ice on lakes and rivers. What is known, is that ice cover for freshwaters in the northern hemisphere has steadily declined for the last 150 years, putting people’s cultural and spiritual practices at risk, and potentially their livelihoods, report York University biologist Sapna Sharma and colleagues.

Researchers note that in recent decades most of the lakes and rivers in the world’s cooler climates freeze later in the season and thaw earlier, or do not freeze at all anymore.

“The loss of ice currently affects 14,800 lakes and impacts cultural ecosystem services in all those surrounding communities, including food subsistence, transportation, religious ceremonies and recreational opportunities,” said Sharma, an associate professor in the Faculty of Science and co-author of a recent study on the cultural impacts of ice loss on inland lakes and rivers in Limnology and Oceanography Letters. “Cultural ecosystem services are an underappreciated resource directly affected by climate change and that is impacting communities that rely on freshwater ice now.”

For example, ice roads serve 31 remote Indigenous communities in northern Ontario and 18 in Manitoba, often connecting communities in the north to those in the south. Across northern Canada, the opening of ice roads has been delayed at times by as much as three weeks, yet winter ice roads are crucial for social, mental health and financial reasons.

As places across the northern hemisphere deal with warmer winters, events that are socio-economically and culturally important to local communities, like ice fishing tournaments, cross-country skiing and ice-skating races, are increasingly cancelled.

The impacts of ice loss aren’t limited to culturally important activities in Canada. Since the 15th century, Catholic priests in Germany carried a statue of John the Apostle across a frozen Lake Constance to a church in Switzerland as a sign of friendship. Lake Constance last froze in 1963 and with it the last procession between the two countries.

In Japan, Shinto priests have collected lake ice records for centuries and have celebrated the “crossing of the gods,” an event commemorating the annual formation of ice cover, since 1443. Since 1988, the lake only freezes twice every decade.

“While each of these issues may seem like only a local concern, for the millions of people living in places where winter ice is in retreat, they add up to a major shift in their relationship to winter,” said Sharma. “It is time freshwater ice loss is included in the list of major climate change impacts.”

Associate Professor Sapna Sharma, an expert in environmental stressors on lakes can comment on:

  • The effect of climate change, winter warming, on northern hemisphere communities
  • The loss of ice-related cultural ecosystem services, education and research, artistic, recreation (ice-skating and ice fishing competitions) and ceremonial practices
  • The threat to a way of life
  • The benefits these cultural ecosystem services provide communities
  • Impact of environmental stressors on lakes


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Media Contact:

Sandra McLean, York University Media Relations, 416-272-6317,