Lakes warming at alarming rates

Public Release: 16-Dec-2015
Lakes warming at alarming rates, York U-led global study warns
Warming of lakes at a rapid rate, even faster than the air or the oceans: Study
York University

Climate change has led to warming of lakes at a rapid rate, even faster than the air or the oceans, according to York U Biologist Sapna Sharma, a lead author of a new global study.

"We found that lakes are warming at an average of 0.34 degrees Celsius each decade all around the world, threatening freshwater supplies and ecosystems," Professor Sharma says. "This can have profound effects on drinking water and the habitat of fish and other animals."

The study predicts that at the current rate, algal blooms, which can ultimately rob water of oxygen, will increase 20 per cent in lakes over the next century. Algal blooms that are toxic to fish and animals would increase by five per cent. These rates also imply that emissions of methane, a greenhouse gas 25 times more powerful than carbon dioxide, will increase four per cent over the next decade.

"We found that ice-covered lakes, including Canadian lakes, are warming twice as fast as air temperatures and the North American Great Lakes are among the fastest warming lakes in the world," Sharma notes.

In total, 236 lakes were monitored annually for the past 25 years. "While that's a fraction of the world's lakes, they contain more than half the world's freshwater supply," says Sharma.

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