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.

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

LETTER: Why are mobile lab workers not getting hazard pay?

A Pitt Meadows essential service worker questions why she and coworkers are not being compensated

PHOTOS: Maple Ridge Cubs conduct porch-based food drive

A Scouting from Home effort sees kids collecting non-perishables for the Friends In Need Food Bank

A second wave of COVID-19 is probable, if history tells us anything

B.C.’s top doctor says that what health officials have learned this round will guide response in future

LETTER: Hear your postie’s plea about dogs

When a canine bites, it’s seldom the animal but rather the owner at fault

Gifted tablet help connect patients with loved-ones

Amid COVID, Ridge Meadows Hospital continues to receive a variety of different kinds of donations

LIVE: Procession to honour Snowbirds Capt. Jennifer Casey comes to Halifax

Snowbirds service member died in a crash in Kamloops one week ago

Facing changes together: Your community, your journalists

Thanks for helping The News to continue its mission to provide trusted local news

RCMP facing ‘systemic sustainability challenges’ due to provincial policing role

Provinces, territories and municipalities pay anywhere from 70 to 90 per cent of the cost of the RCMP’s services

‘Not a joke’: Promoter wants to rocket-launch man the length of White Rock pier

Brooke Colby says he’s building an eight-foot rocket in his backyard

One man dead after standoff with Chilliwack RCMP

The Independent Investigations Office of B.C. is investigating the RCMP’s role in the death

B.C. employers worry about safety, cash flow, second wave in COVID-19 restart

A survey found 75 per cent of businesses worry about attracting customers

Ex-BC Greens leader Andrew Weaver says province came close to early election

Disagreement centred on the LNG Canada project in northern B.C.

Canada’s NHL teams offer options to season-ticket holders

Canadian teams are offering refunds, but also are pushing a number of incentives to let them keep the money

Boy, 2, left with ‘soft tissue injuries’ after being hit by car in Squamish intersection

Boy was release from hospital, police continue to investigate

Most Read