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

UPDATE: Power restored to Vernon

Power went down around 4:30 p.m. in the middle of the city, reportedly caused by vandalism

Okanagan-Shuswap weather: mix of sun and clouds

Environment Canada is predicting a 30 per cent chance of showers and a risk of thunderstorms this afternoon across the Okanagan

Vernon pageant participant heads stateside

Samantha Sewell will represent North America at Miss Royalty International in Milwaukee

Vernon summer mural tours start with new guides

The mural tours started on June 28 and will run until Sept. 27

PHOTOS: Armstrong MetalFest rocks Hassen

Big crowds gather for popular two-day annual heavy metal music festival

VIDEO: Okanagan Valley weekday weather update

Environment Canada says it’s going to be a rainy week

Asylum figures show overall slower rate of irregular crossings into Canada

Between January and June 2019, a total of 6,707 asylum seekers crossed irregularly into Canada

U.S. tug firm to be sentenced for 2016 spill in B.C. First Nation’s territory

he Nathan E. Stewart spilled 110,000 litres of diesel and heavy oils in October 2016

Boy’s best friend gets help from South Okanagan community

Community rallies around dog that needed surgery for two broken legs

Youth seen with gun at Nanaimo mall, suspect now in custody

Woodgrove Centre shut down during police incident

B.C. man dies from rabies after contact with Vancouver Island bat

Last known case of human rabies in B.C. was 16 years ago

Crown recommends up to two-year jail term for former Bountiful leader

Crown says sentence range should be 18 months to two years for Bountiful child removal case

B.C.-wide police efforts identify Vancouver Island robbery suspect

Warrant issued for arrest of North Vancouver man for TD Bank robbery

VIDEO: Wolf spotted swimming ashore on northern Vancouver Island

Island wolf population estimated at under 150 in 2008, says VI-Wilds

Most Read