Latest news with #HamidGhanbari
Winnipeg Free Press
5 days ago
- Science
- Winnipeg Free Press
Climate change major driver of surging algae levels in Canada's lakes: study
TORONTO – A study of dozens of Canadian lakes suggests global warming is the major driver of surging algae levels, raising questions about the health of a sizable chunk of Earth's freshwater as temperatures continue to climb. Average algae levels have spiked seven-fold since around the 1960s compared to the previous century, according to a study of 80 lakes across Canada. Those changes were more pronounced in lakes near human impacts on the environment but were still seen far away from farms, mines and forestry, the study said. 'Even lakes in pristine catchments are vulnerable to change,' said the study, published last month in Communications Earth and Environment. To try to explain what's behind that spike, researchers looked at other possible algae influences such as rain, the sun's radiation and land use changes, such as farming. Temperature was the leading factor the study associated with surging algae growth. 'This is a warning,' said Hamid Ghanbari, the study's lead author and a post-doctoral researcher at Université Laval in Quebec City. The study doesn't determine which lakes are facing dangerous levels of algae growth or account for toxic algal blooms. The seven-fold increase since the 1960s is an average across the 80 studied lakes. Some with low algae levels to begin with are still at fairly low levels. But for lakes with lots to begin with, a seven-fold increase could lead to problems, including toxic algal blooms, researchers said. 'If (algae growth) reaches a level of being considered dangerous, we will see some consequences. It's going to harm the lake ecosystem, it's going to hurt the wildlife around it, and it's also going to hurt our wallet,' said Ghanbari. Algae are at the base of the lake's food web, feeding the small fish and zooplankton that then feed the larger fish, and so on. But too much algae growth can suck the oxygen out of the bottom of the lake, leading to large fish kills and so-called 'dead zones' where it's hard for aquatic life to survive. Toxic algal blooms are also a persistent issue for some of Canada's drinking water sources, from Saskatchewan's Buffalo Pound Lake to Ontario's Bay of Quinte, leading to taste, odour and safety concerns and prompting upgrades to local treatment facilities. Contaminated lake water can also be deadly for dogs and cattle. Pollution packed with nitrogen and phosphorus, such as from fertilizers or stormwater runoff, can fuel algae growth. And what this study shows is lakes already dealing with direct human impacts are even more vulnerable to climate change, said Katrina Eyvindson, the chair of Western University's geography and environment department, who was not involved in the project. 'I think that's what's really key in this research,' she said, calling the project an 'impressive undertaking.' The research team led by scientists at Laval and McGill University pieced together an algae chronology that starts in 2014 and dates back all the way to 1850 by studying chlorophyll levels in lake sediment cores. Chlorophyll, molecules critical in turning sunlight to plant energy, are a proxy for algae and cyanobacteria known as blue-green algae, which also performs photosynthesis. Those samples were drawn from lakes covering a massive swath of Canada and facing different conditions. Wednesdays What's next in arts, life and pop culture. By the mid 1960s – a 'breakpoint' identified by the researchers – both temperature and chlorophyll increases began to accelerate. Climate change, driven by the burning of fossil fuels, is warming Canada about twice as fast as the global average. Since the mid-20th century, average temperatures in Canada have increased by 2.4C degrees, federal records indicate. The findings underscore the urgent need to fight climate change and protect Canada's lakes, said Irene Gregory-Eaves, a McGill biology professor and study co-author. Canada has the most lakes of any country and holds about seven per cent of the world's renewable fresh water. 'I would hope that this is like a big megaphone for, you know, getting people interested in climate change, trying to put pressure on government to make sure that strong policies and laws are in place to bend the curve on emissions,' she said. This report by The Canadian Press was first published Aug. 7, 2025.
Yahoo
6 days ago
- Health
- Yahoo
What's slimy, green and flourishing thanks to climate change?
If you guessed algae, you're right. New research published in Communications Earth & Environment suggests algae growth is increasing in Canada's lakes — even remote ones — and climate change is the main culprit. A team led by researchers at McGill University in Montreal and Université Laval analyzed sediment cores taken from 80 lakes across the country and found that algae has been increasing in the majority of them since the mid-1800s. For lead author Hamid Ghanbari, the most interesting finding was a spike in the rate of the increase in algal growth: since the 1960s, it increased sevenfold. "This was something very surprising for us and when we compared our data with other historical records, we found out that rising temperature is a major factor," Ghanbari said. Aside from climate change, excess nitrogen and phosphorus can also contribute to algal growth when they are carried into waterways through runoff from animal manure and chemical fertilizers, stormwater and wastewater. Algae, along with bacteria and phytoplankton, are essential for the aquatic food web. But too much algae can be a bad thing. The recently published peer-reviewed study looked at algal growth overall and didn't analyze for blooms. While some lakes see some algae as a part of their cycle, Ghanbari said the concern is what will happen if the increase in algae leads to growth outside of what's normal. "That's where the problem starts," he said. "We don't know at the moment what that threshold is, but we know the increasing chlorophyll or algae levels in the lakes could lead to several problems." Ghanbari said excess algae growth can harm aquatic life and even human health — reducing water quality, depleting oxygen in the water and creating blooms that can release dangerous toxins, as residents along the shores of Lake Erie know all too well. Daryl McGoldrick, head of water quality monitoring and surveillance for the Great Lakes for Environment and Climate Change Canada, said while increasing algal growth doesn't necessarily mean more toxic blooms, there is a risk to aquatic life. "The study is in line with what we see and [what we] suspect are impacts of warming," McGoldrick said. Global and local action can help Maëlle Tripon, a project manager with Quebec freshwater advocacy group Fondation Rivières, said her team has noticed first-hand that when it's warmer, they see more algae on lakes. She said her takeaway from the research is that tackling algal growth cannot solely rely on local action. "We already knew we need to change locally — like farming practices and also, for example, we need less paved and waterproof surface in the cities," she said. "But what the study shows is that we also need global policies to alleviate climate change." Ghanbari agreed, but added that individual choices can still help reduce algal growth. "Simple acts such as reducing the fertilizers … or properly disposing of household chemicals, these simple acts could really help the lakes," he said.
CBC
6 days ago
- Health
- CBC
What's slimy, green and flourishing thanks to climate change?
If you guessed algae, you're right. New research published in Communications Earth & Environment suggests algae growth is increasing in Canada's lakes — even remote ones — and climate change is the main culprit. A team led by researchers at McGill University in Montreal and Université Laval analyzed sediment cores taken from 80 lakes across the country and found that algae has been increasing in the majority of them since the mid-1800s. For lead author Hamid Ghanbari, the most interesting finding was a spike in the rate of the increase in algal growth: since the 1960s, it increased sevenfold. "This was something very surprising for us and when we compared our data with other historical records, we found out that rising temperature is a major factor," Ghanbari said. Aside from climate change, excess nitrogen and phosphorus can also contribute to algal growth when they are carried into waterways through runoff from animal manure and chemical fertilizers, stormwater and wastewater. Algae, along with bacteria and phytoplankton, are essential for the aquatic food web. But too much algae can be a bad thing. The recently published peer-reviewed study looked at algal growth overall and didn't analyze for blooms. While some lakes see some algae as a part of their cycle, Ghanbari said the concern is what will happen if the increase in algae leads to growth outside of what's normal. "That's where the problem starts," he said. "We don't know at the moment what that threshold is, but we know the increasing chlorophyll or algae levels in the lakes could lead to several problems." Ghanbari said excess algae growth can harm aquatic life and even human health — reducing water quality, depleting oxygen in the water and creating blooms that can release dangerous toxins, as residents along the shores of Lake Erie know all too well. Daryl McGoldrick, head of water quality monitoring and surveillance for the Great Lakes for Environment and Climate Change Canada, said while increasing algal growth doesn't necessarily mean more toxic blooms, there is a risk to aquatic life. "The study is in line with what we see and [what we] suspect are impacts of warming," McGoldrick said. Global and local action can help Maëlle Tripon, a project manager with Quebec freshwater advocacy group Fondation Rivières, said her team has noticed first-hand that when it's warmer, they see more algae on lakes. She said her takeaway from the research is that tackling algal growth cannot solely rely on local action. "We already knew we need to change locally — like farming practices and also, for example, we need less paved and waterproof surface in the cities," she said. "But what the study shows is that we also need global policies to alleviate climate change." Ghanbari agreed, but added that individual choices can still help reduce algal growth. "Simple acts such as reducing the fertilizers … or properly disposing of household chemicals, these simple acts could really help the lakes," he said.
