This Sept. 26, 2019 photo shows coastal waters off Greenwood State Beach where The Nature Conservancy is mapping and monitoring one of Mendocino County’s last remaining bull kelp forests near Elk, Calif. (AP Photo/Terry Chea)

This Sept. 26, 2019 photo shows coastal waters off Greenwood State Beach where The Nature Conservancy is mapping and monitoring one of Mendocino County’s last remaining bull kelp forests near Elk, Calif. (AP Photo/Terry Chea)

Scientists breathe easier as marine heat wave off west coast weakens

Area of exceptionally warm water is substantially smaller now than it was earlier this year

Scientists say a marine heat wave that blanketed a large area of the west coast has weakened, but the potential disruption to ocean life isn’t over yet.

Nate Mantua of the National Oceanic and Atmospheric Administration said the ”good news” is that the area of exceptionally warm water is substantially smaller now than it was earlier this year.

And while the area about 1,500 kilometres offshore between Hawaii and Alaska is still seeing high temperatures by historical standards, it is “simply not nearly as large as it was and it is no longer strong in areas near the west coast,” he said.

Scientists have been watching a marine heat wave that developed around June this year and resembled a phenomenon that was nicknamed ‘The Blob,’ which disrupted ocean life between 2014 and 2016.

The heat wave, which resembles a wedge this time, stretched from south of Vancouver Island to Baja, Calif., and offshore towards Hawaii. It raised temperatures by up to 4 C.

Mantua said “many energetic storms and unusually strong winds from the north off the west coast” have cooled surface waters back to near normal temperatures for much of the region.

“On the other hand, the offshore warming is still in place, and by historical standards, it is still a large marine heat wave,” he said in an email.

The latest climate model forecasts from the National Oceanic and Atmospheric Administration’s Climate Prediction Center suggest that the offshore warming will gradually weaken over the next seven months, but even by spring will still be warmer than normal, Mantua said.

ALSO READ: Students skip school, join climate strikes across B.C.

Prof. Andrew Trites at the University of British Columbia’s Institute for the Oceans and Fisheries said the marine heat wave is caused when there is not enough wind to churn and cool the water.

“This past summer winds were very, very light — not strong enough for ocean to be mixed the way it used to be in the past. As a result the ocean didn’t cool down the way it was supposed to and it’s holding its heat,” he said in a phone interview.

“It’s not that the ocean got warmer, it’s really that the ocean did not get cooler.”

As a result, some species of tropical fish that are usually seen in tropical waters were found off the west coast, he said.

“One of the fish that I saw a lot of this summer was the sunfish and presumably they are here in higher numbers because the water here was unusually warm this summer and they can tolerate warm temperatures,” Trites said.

Mantua said the most obvious impacts included a pattern of unusually low plankton production from July through September from Vancouver Island to northern California.

Warm waters near the coast of northern California, Oregon, and southern Washington brought albacore tuna closer than normal to the coast, and sport fishing was especially good there this summer, he said.

However, ocean salmon fishing in those areas was generally poor, Mantua said.

“All that said, I have not heard of any reported ecosystem impacts in those offshore waters where it remains very warm,” he said.

“I suspect that the extreme warming in the productive part of the open ocean has had some impacts, but there simply isn’t a lot of information coming from those regions aside from satellite observations of ocean colour that tell us some general information about plankton production.”

There is a chance that the marine heat wave might return, Mantua said, although he thinks “the odds for that are low, at least based on the latest climate forecasts.”

Trites said the first time this heat wave occurred about five years ago, it was thought that it would never happen again.

“So this may be an example of climate change and global warming. It is changing the patterns of air circulation and affecting storminess and it’s not going to mix the water the way it used to.”

Hina Alam, The Canadian Press

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

Just Posted

Nuxalk Public Health Nurse Sophie Mack is all smiles as she vaccinates her dad, hereditary chief James Mack Sr., with his first dose of the Moderna vaccine (photo submitted)
Cases drop as vaccine continues to roll out in Bella Coola

Seniors at Mountain View Lodge, Nuxalk elders, hospital staff and long-term care residents have all started to receive their vaccines so far

Interior Health has declared the Cariboo Chilcotin a community cluster. (Angie Mindus photo)
Interior Health declares Cariboo Chilcotin region a COVID-19 cluster, 215 cases since Jan. 1

Most cases are related to transmission at social events and gatherings in Williams Lake

A vial of the Moderna COVID-19 vaccine is displayed on Jan. 5, in Salt Lake City, Utah. (Rick Bowmer/AP)
Power outage spoils COVID-19 vaccine at Tl’etinqox

Temperature-sensitive vaccine no longer viable after Jan. 18 event

Nuxalk elder Caroline Mack, 85, receives her first dose of the Moderna vaccine on Jan. 19, at the Nuxalk Hall. (Caitlin Thompson photo)
First vaccines roll out for Nuxalk elders, hospital staff and long-term care residents

The Moderna vaccine arrived in Bella Coola on Sunday, Jan. 17

Toronto Public Health nurse Lalaine Agarin sets up for mass vaccination clinic in Toronto, Jan. 17, 2021. B.C. is set to to begin its large-scale immunization program for the general public starting in April. THE CANADIAN PRESS/Frank Gunn
B.C.’s COVID-19 mass vaccinations expected to start in April

Clinics to immunize four million people by September

Chief Public Health Officer Theresa Tam speaks during a daily briefing in Ottawa. (THE CANADIAN PRESS/Adrian Wyld)
31 cases of COVID-19 variants detected in Canada: Health officials

Dr. Theresa Tam made announces 13 more variant COVID-19 cases in Canada

An Atlantic salmon is seen during a Department of Fisheries and Oceans fish health audit at the Okisollo fish farm near Campbell River, B.C. in 2018. The First Nations Leadership Council says an attempt by industry to overturn the phasing out of salmon farms in the Discovery Islands in contrary to their inherent Title and Rights. (THE CANADIAN PRESS /Jonathan Hayward photo)
First Nations Leadership Council denounces attempt to overturn salmon farm ban

B.C.’s producers filed for a judicial review of the Discovery Islands decision Jan. 18

Daily COVID-19 cases reported to each B.C. health region, to Jan. 20, 2021. Island Health in blue, Northern Health green, Interior Health orange, Vancouver Coastal in red and Fraser Health in purple. (B.C. Centre for Disease Control)
B.C.’s COVID-19 infection rate stays stable with 508 cases Friday

Vaccine delivered to more than 110,000 high-risk people

More than 100 B.C. fishermen, fleet leaders, First Nations leaders and other salmon stakeholders are holding a virtual conference Jan. 21-22 to discuss a broad-range of issues threatening the commercial salmon fishery. (Black Press file photo)
B.C. commercial salmon fishermen discuss cures for an industry on the brink

Two-day virtual conference will produce key reccomendations for DFO

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

The District of Saanich’s communications team decided to take part in a viral trend on Thursday and photoshopped U.S. Senator Bernie Sanders into a staff meeting photo. (District of Saanich/Twitter)
Bernie Sanders makes guest appearance municipal staff meeting in B.C.

Vancouver Island firefighters jump on viral trend of photoshopped U.S. senator

School District 57 headquarters in Prince George. (Mark Nielsen, Local Journalism Initiative Reporter)
Prince George school district settles with sexual abuse victim

Terms were part of an out-of-court settlement reached with Michael Bruneau, nearly four years after he filed a lawsuit

Surrey provincial court. (File photo: Tom Zytaruk)
New COVID-19 protocols set for provincial courthouses

The new rules were issued on Jan. 21, and took effect immediately

Most Read