In hot water? Study says warming may reduce sea life by 17%

Every degree Celsius that the world’s oceans warm, the total mass of sea animals is projected to drop by 5 per cent

The world’s oceans will likely lose about one-sixth of their fish and other marine life by the end of the century if climate change continues on its current path, a new study says.

Every degree Celsius that the world’s oceans warm, the total mass of sea animals is projected to drop by 5%, according to a comprehensive computer-based study by an international team of marine biologists. And that does not include effects of fishing.

If the world’s greenhouse gas emissions stay at the present rate, that means a 17% loss of biomass — the total weight of all the marine animal life — by the year 2100, according to Tuesday’s study in the Proceedings of the National Academy of Sciences. But if the world reduces carbon pollution, losses can be limited to only about 5%, the study said.

“We will see a large decrease in the biomass of the oceans,” if the world doesn’t slow climate change, said study co-author William Cheung, a marine ecologist at the University of British Columbia. “There are already changes that have been observed.”

While warmer water is the biggest factor, climate change also produces oceans that are more acidic and have less oxygen, which also harms sea life, Cheung said.

Much of the world relies on the oceans for food or livelihood, scientists say.

READ MORE: Canada to ban single-use plastics in 2021

“The potential ramifications of these predicted losses are huge, not just for ocean biodiversity, but because people around the world rely on ocean resources,” said University of Victoria biology professor Julia Baum, who wasn’t part of the study but says it makes sense. “Climate change has the potential to cause serious new conflicts over ocean resource use and global food security, particularly as human population continues to grow this century.”

The biggest animals in the oceans are going to be hit hardest, said study co-author Derek Tittensor, a marine ecologist at the United Nations World Conservation Monitoring Center in England.

“The good news here is that the main building blocks of marine life, plankton and bacteria may decline less heavily, the bad news is that those marine animals that we use directly, and care about most deeply, are predicted to suffer the most as climate change is working its way up the food chain,” co-author Boris Worm, a marine biologist at Dalhousie University in Canada, said in an email.

Tropical areas, already warm, will also see the biggest losses, Cheung said.

Scientists had already thought that climate change will likely reduce future ocean life, but past computer simulations looked at only part of the picture or used only one model. This study uses six different state-of-the-artcomputer models thatgive the best big picture look yet, Cheung said.

It is hard to separate past climate change impacts from those of fishing, but past studies have shown places where observed fish loss can be attributed to human-caused climate change, Chung added.

Tittensor pointed to lobsters off Maine and North Atlantic right whales as examples of creatures already being hurt by global warming hitting the ocean.

University of Georgia marine biologist Samantha Joye, who wasn’t part of the research, praised the study as meticulous and said it is also “an urgent call for action.”

“Healthy oceans are required for planetary stability,” Joye said in an email. “Aggressive global action to slow climate change is a moral imperative.”

Seth Borenstein, The Associated Press

Like us on Facebook and follow us on Twitter.

Just Posted

Kootenay-Columbia incumbent MP responds to Trudeau brownface scandal

Stetski proud of NDP leader Singh’s reaction, which focused on people not power

Liberals’ Kootenay-Columbia candidate stands by Trudeau despite scandal

Robin Goldsbury says the prime minister’s racist photo is a learning opportunity

Aquifers, water quality exceedances, and concerns for drinking water in Golden and Area A

Water quality and quantity issues are reaching a pinnacle in Golden and… Continue reading

Golden Landfill receives second operational warning letter from MoE

The Ministry of Environment (MoE) has issued a second warning letter to… Continue reading

Two Global Climate Action Strikes taking place in Golden on September 20

Two events in Golden are taking place simultaneously as others across the… Continue reading

VIDEO: B.C. man accused of assaulting sex worker loses temper in interrogation

Defence lawyer says statements made by accused Curtis Sagmoen should be deemed inadmissible

B.C. man guilty of first-degree murder in Yukon killing

Edward James Penner, 22, was given the mandatory life sentence for the 2017 slaying of 25-year-old Adam Cormack

Victoria man spots online photo of his totem pole 11 years after it was stolen

Mark Trueman restored the pole himself before it was stolen off of his property in Duncan

‘I’d do it again,’ says B.C. man who swam naked, drunk in Toronto shark tank

David Weaver, of Nelson, was drunk when he went to Ripley’s Aquarium in Toronto on Oct. 12 2018

How to react to Trudeau’s racist photos? With humility, B.C. prof says

‘We are now treating racism as a crime that you cannot recover from’

Woman stabbed at least five times in Nelson during random attack

Victim is in hospital, suspect is in police custody

Horvat paces Canucks to 6-1 pre-season win over Oilers

Vancouver improves to 3-1 in NHL exhibition action

Legislature gifts, clothing, travel need better control, B.C. auditor says

Audit follows suspensions of managers by Speaker Darryl Plecas

‘Really disturbing:’ Trudeau’s racist photos worry B.C. First Nation chief

Wet’suwet’en Chief concerned the photos will sow fear in Indigenous communities

Most Read