{"id":34945,"date":"2024-09-19T13:39:15","date_gmt":"2024-09-19T17:39:15","guid":{"rendered":"https:\/\/www.yorku.ca\/science\/?p=34945"},"modified":"2024-09-27T11:25:59","modified_gmt":"2024-09-27T15:25:59","slug":"lake-ice-quality-degrading-as-planet-warms","status":"publish","type":"post","link":"https:\/\/www.yorku.ca\/science\/2024\/09\/19\/lake-ice-quality-degrading-as-planet-warms\/","title":{"rendered":"Lake ice quality degrading as planet warms"},"content":{"rendered":"\n

Media release from September 19, 2024<\/a><\/p>\n\n\n\n

Several studies have looked at lake ice quantity and its duration, but there is little research on the quality of the ice which directly corresponds to how safe it is to venture out on.<\/em><\/p>\n\n\n\n

Ice may look safe for a game of pick-up hockey on the lake, but as a new study out of 快播视频 found, looks can be deceiving. Warming winters are not only affecting ice thickness and timing \u2013 when a lake freezes and thaws \u2013 but also quality, making it potentially unstable and unsafe.<\/p>\n\n\n\n

When lakes and rivers freeze, there are two predominant layers of ice, what\u2019s called white ice and black ice. White ice is generally opaque, like snow, and filled with more air bubbles and smaller ice crystals, diminishing its strength and stability, while black ice is clear and dense with few air pockets and larger ice crystals making it a lot stronger.<\/p>\n\n\n\n

\u201cIce quality is important because of its direct implications for load bearing capacity for human safety and also how much light will transmit under ice for life under frozen lakes,\u201d says York Professor Sapna Sharma.<\/p>\n\n\n

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Researchers measure ice thickness in lake ice. Photo by is Aman Basu, a PhD student in Sapna Sharma\u2019s lab<\/figcaption><\/figure>\n<\/div>\n\n\n

The problem, says lead author and York Postdoctoral Fellow Joshua Culpepper, is that the unpredictable and warmer winter weather is creating thinner layers of black ice and sometimes a corresponding thicker layer of white ice, the unstable kind. The two combined can make for treacherous conditions for skaters, hockey players, snowmobilers, ice anglers and ice truckers.<\/p>\n\n\n\n

\u201cWe know that in general, lake ice is forming later in the season and breaking up earlier, which implies an overall shorter duration of ice cover, but our study looked at what the ice is doing. How is it changing? You might get periods of time when people are on the ice and they think it\u2019s safe, but it really isn\u2019t. It\u2019s not sufficiently thick enough given the changes in the quality,\u201d says Culpepper.<\/p>\n\n\n\n

10 cm no longer the golden rule<\/strong><\/p>\n\n\n\n

Thickness alone is no longer a good predictor of safe ice. If there is too much white ice and not enough black ice, the ice it may not be strong enough to hold a person\u2019s weight. It\u2019s what the researchers are calling a dangerous combination.<\/p>\n\n\n\n

\u201cFor a human to go out on the ice to skate or play, that requires about 10 centimeters or four inches of black ice\u2026but what we\u2019re seeing and what we\u2019re predicting is that climate change is contributing to more white ice conditions,\u201d says Sharma, who recommends people measure the ice and if there is only a thin layer of black ice to double the usual recommended thickness to at least 20 cm.<\/p>\n\n\n\n

\u201cBlack ice is clear and there\u2019s no slush. You shouldn\u2019t be walking over slush,\u201d says Sharma, she adds that it\u2019s always best to go with someone or a group.<\/p>\n\n\n\n

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