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

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

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

Pioneer Arena is closing for the season. Photo: John Boivin
Castlegar’s Pioneer Arena and Nelson Civic Centre closing for season

RDCK is closing the ice at two of its arenas due to financial concerns related to COVID-19

Interior Health update. File photo.
86 new COVID-19 cases, two more deaths in Interior Health

The new deaths are from Heritage Square, a long-term care facility in Vernon

A performance by Alex Cuba will be streaming live on Arts Revelstoke platforms on Feb. 12, 2021. (Photo by Jeff Fasano, submitted by Arts Revelstoke)
Arts Revelstoke hosting virtual performances and movies this season

REVY. Live and Movies in the Mountains is returning

Summit Ski Hill had a delayed start to the season because of warm temperatures. Photo: Summit Ski Hill
Late season start frustrating for Nakusp ski hill

Summit Ski Hill only just opened Jan. 14

Four friends were heading to their home on Highway 6 just south of Silverton on the evening of Dec. 25, 2020, when the people in the front of the vehicle saw what looked like a “huge, man-like figure” on the side of the road. (Pixabay.com)
Possible Bigfoot sighting shocks, excites Silverton residents

‘I didn’t see the creature myself, I saw the prints’

Keith the curious kitten is seen on Nov. 4, 2020 at the Chilliwack SPCA. Friday, Jan. 22, 2021 is Answer Your Cat’s Questions Day. (Jenna Hauck/ Chilliwack Progress file)
Unofficial holidays: Here’s what people are celebrating for the week of Jan. 17 to 23

Answer Your Cat’s Questions Day, Pie Day and International Sweatpants Day are all coming up this week

(Phil McLachlan - Capital News)
‘Targeted’ shooting in Coquitlam leaves woman in hospital

The woman suffered non-life threatening injuries in what police believe to be a targeted shooting Saturday morning

JaHyung Lee, “Canada’s oldest senior” at 110 years old, received his first dose of the COVID-19 vaccine on Thursday, Jan. 14, 2021. He lives at Amenida Seniors Community in Newton. (Submitted photo: Amenida Seniors Community)
A unique-looking deer has been visiting a Nanoose Bay property with its mother. (Frieda Van der Ree photo)
A deer with 3 ears? Unique animal routinely visits B.C. property

Experts say interesting look may be result of an injury rather than an odd birth defect

Standardized foundation skills assessment tests in B.C. schools will be going ahead later than usual, from Feb. 16 to March 12 for students in Grades 4 and 7. (Black Press Media file photo)
B.C. teachers say COVID-affected school year perfect time to end standardized tests

Foundational skills testing of Grade 4 and 7 students planned for February ad March

Sooke’s Jim Bottomley is among a handful of futurists based in Canada. “I want to help people understand the future of humanity.” (Aaron Guillen - Sooke News Mirror)
No crystal ball: B.C. man reveals how he makes his living predicting the future

63-year-old has worked analytical magic for politicians, car brands, and cosmetic companies

Terry David Mulligan. (Submitted photo)
Podcast: Interview with longtime actor/broadcaster and B.C. resident Terry David Mulligan

Podcast: Talk includes TDM’s RCMP career, radio, TV, wine, Janis Joplin and much more

Seasonal influenza vaccine is administered starting each fall in B.C. and around the world. (Langley Advance Times)
After 30,000 tests, influenza virtually nowhere to be found in B.C.

COVID-19 precautions have eliminated seasonal infection

Prime Minister Justin Trudeau listens to a question during a news conference outside Rideau cottage in Ottawa, Friday, January 8, 2021. THE CANADIAN PRESS/Adrian Wyld
Trudeau says Canada’s COVID vaccine plan on track despite Pfizer cutting back deliveries

Canadian officials say country will still likely receive four million doses by the end of March

Most Read