Climate change is raising the temperature of lakes

Zoom Layland Masuda

There's a reason, but when it comes to bodies of water and climate change, the ocean gets (sea lions) attention. But on earth, about 117 million water bodies, albeit smaller ones, play necessary ecological, social and economic roles. Lakes are relatively small, but "relative" is a key term there - for example, the Great Lakes of North America account for 20% of Earth's fresh surface water. We also rely on them for food, fresh water, transportation, etc.

New research identifies interrelated challenges facing the world's lakes. According to Sapna Sharma, co-author of the research and associate professor in York University's Department of Biology, many of the climate change-related impacts that these waterholes remain relatively hidden despite these waters potentially facing a vast collection of problems. “I hope people will get an idea of ​​the magnitude of the effects of climate change on the lakes,” she told Ars. "If you just go and look at a lake, you might not know all the changes it is going through."

To investigate this, Sharma and his colleagues from different universities around the world looked at hundreds of research papers on lakes. These documents come from all over the world and some date back to the 1930s, she said. Sharma and his fellow researchers all have different areas of expertise, allowing them to review and synthesize the existing literature.

Sharma noted that there are a number of other articles that all focus on different aspects of the impact of climate change on lakes, but they tend to focus on particular niches, rather than the phenomenon as a whole. "Putting it in one document, in one article, was the novelty," she said.

Smoking on (or sometimes near) water

The hundreds of articles painted a complex picture of the past, present and future of lakes in a rapidly changing climate. On a purely mechanical level, a warmer planet means less ice cover. Increasingly, ice takes longer to grow on lakes in fall and winter, and it disappears earlier in spring and summer.

Heat also causes the waters to stratify faster, which means colder, heavier water will sink under warmer, lighter water. Additionally, a changing climate can mean lakes experience more droughts or floods due to increased storms.

These mechanical phenomena can wreak havoc on life that depends on the lake for its sustenance or sustenance (in the case of humans). For example, an enhanced seasonal stratification process can increase the likelihood of harmful algal blooms that can use a lake's oxygen and kill its other occupants. Algal blooms can also impact water quality for humans. Some lake fish prefer to live in cooler, deeper water, so a warming lake could encroach on their habitats.

The human element

All of this, in turn, can impact humans culturally and economically, Sharma said. In some cases, an annual decrease in lake ice can lead to the cancellation of ice fishing tournaments, ski races and similar events. These events can be very attractive to small communities and bring in a lot of money for tourism.

Regular algae blooms on a lake can also decrease the property value of nearby homes or cottages. Around the world, these issues are more likely to impact marginalized people, Sharma added. For example, algal blooms can make local water undrinkable for some