Professor talks climate change & rising water levels in Lake Ontario

John Smol explains high water levels at Gord Edgar Downie pier this year

Professor John Smol talks rising water levels.
Supplied by John Smol

Over the summer, water levels in Lake Ontario and the St. Lawrence River rose significantly, affecting docks and other coastal infrastructure across Kingston, including the Gord Edgar Downie pier.

In an interview with The Journal, Queen’s professor and Canada Research Chair in Environmental Change, John Smol, discussed the reasons behind the rising water levels.

According to Smol, many indirect factors cause water levels to fluctuate.

“There are some things people see very easily, and there's a lot of things happening that they don't see,” he said. “Changing water levels come down to two main things.”

In the last decade, Smol said there has been extreme weather and less predictability. He said in many areas when there is too much precipitation, the water level goes up, but when there’s too much evaporation, the water level goes down.

“Before, we had a pretty good idea of what the averages were, but now we have these extremes, these episodic extremes, so our predictability is getting much less,” he said.

Smol explained that before extreme weather patterns increased in frequency over the past decade, lakes might have flooded every hundred years. Now, the hundred-year flood is occurring twice in a decade.

At the same time, Smol said warmer conditions will attract exotic and invasive species to the lakes.

“[The exotic species] can ultimately cause harm because they outcompete the native species,” Smol said. “Before weather extremes, the cold could easily stop exotic species from growing, but with a warmer environment, it gives them an opportunity to survive.”

Smol said in addition to rising water levels, algae bloom is also cause for concern. 

According to Smol, algae thrive under hot, stratified conditions. He said with a long summer and longer exposure to light, living organisms like algae, which release toxins and cause infections, photosynthesize.

“Summer has become several weeks longer because of the decreasing ice caps, and that has greatly helped things that we don’t want growing, like blue [and] green algae,” he said.

“[Blue algae] form toxins and cause infections and can hurt dogs and cats,” Smol said. “They release chemicals and they can smell. 

Because of the extremity of the weather, Smol said it’s possible that water levels will decrease next summer.

“[When] it comes to lower water levels in lakes, there’s not enough water for agriculture, people, or animals to survive,” Smol said. “In contrast, the oceans are increasing in water levels, but they’re different.”

He said the ocean’s water levels are increasing because of the heat, and with land-based ice melting from Greenland and Antarctica, freshwater increases or fills in oceans, also causing the water levels to rise.

“People think it’s just the temperature getting warmer, but it’s five hundred other things that are [causing climate change],” Smol said. “It’s the indirect effects that are really causing the problems. Rising water levels make headlines, but there are a lot more important things.”

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