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

First Nations included in latest Columbia River Treaty talks

Seventh round of negotiations between Canada and U.S. wrap up in Washington D.C.

Runners hit the streets for Special Olympics

Cranbrook RCMP teamed up with Cranbrook Safeway on Saturday, June 22, for… Continue reading

School board reports January malware attack

Email systems compromised at board office and Fernie Learning Centre, according to memo

Bowen Byram goes fourth overall in the 2019 NHL Entry Draft

The Cranbrook native was picked by the Colorado Avalanche in the NHL draft

Residents asked to leave ‘fawn in area’ signs alone

Signs are there for the protection of deer and people

Video shows fireworks shot at swan in Alberta

Alberta Fish and Wildlife is investigating the incident in Grande Prairie

‘Text neck’ causing bone spurs to grow from millennials’ skulls, researchers say

Technology use from early childhood causing abnormal bone growths in 41 per cent of young adults

B.C. teen killed by fallen tree on field trip remembered as hero

13-year-old Tai Caverhill was the first to spot the tree falling and warned his friends

Surrey RCMP raises Pride flag amid din of protesters

There were about 30 protesters on either side, and 20 Mounties doing crowd control

Should B.C. get rid of Daylight Saving Time?

The province wants to know, as state governments down south make the move

Air Canada reviewing how crew left sleeping passenger on parked plane

In a Facebook post, the woman said she woke up ‘all alone’ on a ‘cold dark’ aircraft

Canadians crash out of Women’s World Cup in 0-1 loss to Sweden

Canada missed a chance to tie the game on a penalty shot

Four-year-old boy assaulted at B.C. soccer game

It happened at a weekend tournament in Ashcroft

Two bear cubs saved near Revelstoke after mother hit by car

Conservation officers trapped the cubs and transported them to a wildlife sanctuary

Most Read