Noise that vibrates Earth dropped drastically after COVID-19 restrictions: study

Noise that vibrates Earth dropped drastically after COVID-19 restrictions: study

VANCOUVER — An international team of researchers used data from seismic stations in 117 countries to determine that restrictions aimed at preventing the spread of COVID-19 led to an unprecedented drop in noise.

The study published Thursday in the journal Science shows seismic noise, or vibrations generated by human activity, dropped by as much as 50 per cent in March and April, particularly in urban areas.

Mika McKinnon, one of the study’s authors, said they’ve dubbed this quiet period the ”anthropause,” as traffic, planes, cruise ships, conventions, concerts and sports games slowed or stopped.

“We could actually see very sharp cut off starting in China and Italy and then everywhere else as the pandemic spread and the policies and the lockdown spread,” said McKinnon, who teaches in the department of earth, ocean and atmospheric sciences at the University of British Columbia.

And while it was most pronounced in cities, McKinnon said the sound of silence could also be seen in data from an abandoned mine shaft in Germany that’s one of the quietest places on Earth.

A seismic station in Vancouver showed noise levels plummeted when the province closed schools, followed by bars, restaurants and other establishments, she said.

In nearby Seattle, seismic noise dropped later and returned sooner, she added.

“There is a different amount of background noise to start with. But if you look at the percentage decrease, people in Vancouver stayed at home much faster,” said McKinnon.

As the pandemic wears on, she said data from the quiet period will help scientists detect more earthquakes and allow them to better differentiate between human-caused and natural seismic noises.

“We’re getting a much better understanding of what these human-generated wave shapes are, which is going to make it easier in the future to be able to filter them back out again.”

McKinnon said the latest data won’t help predict if and when earthquakes will hit, but it does offer scientists deeper insight into the planet’s seismology and volcanic activity.

The seismic data is also reassuring, she said, because it shows many people are still making less noise while sticking closer to home and following public health guidelines during the pandemic.

The drop in noise is being measured in Earth’s oceans as well, said Richard Dewey, associate director of science at Ocean Networks Canada, based at the University of Victoria.

He likened the pandemic to an unplanned experiment for marine acoustic researchers who have been hoping for years for an opportunity to study the ocean without noise pollution from massive tankers, cruise ships, ferries, whale-watching and commercial-fishing vessels.

So far, data from two monitoring sites off the coast of Vancouver Island shows underwater noise dropped week by week, particlarly in April, as economic activity slowed down, said Dewey.

A quieter ocean is part of the formula that would help the recovery of endangered southern resident killer whales, which return each year to the Salish Sea around southern Vancouver Island, he said.

It’s a tall task to assess whether the orcas’ behaviour has changed in response to the drop in noise, said Dewey, since their calls are unique, and researchers only hear snippets when the southern residents travel past hydrophones that record them.

“We have a pod going by and sometimes you just hear a single whale vocalizing … and sometimes they’re all chatting at the same time. We don’t necessarily know how to interpret that.”

But the general hypothesis is that if the ocean were quieter, the whales could communicate with each other, navigate and assess their environment and acquire food more effectively, said Dewey.

He said researchers will look at data from before, during and after this quiet period to see if they can make distinctions between the meaning, frequency and density of the orcas’ calls.

This report by The Canadian Press was first published July 23, 2020.

Brenna Owen, The Canadian Press

Coronavirus

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

Just Posted

Alberta children whose only symptom of COVID-19 is a runny nose or a sore throat will no longer require mandatory isolation, starting Monday.
477 new COVID-19 cases confirmed in Alberta on Thursday

Changes being made to the COVID-19 symptom list for school-age children

Alisha Bryan holds a handful of poppy sticks at the poppy laying ceremony on Oct. 28. (Alannah Page/Lacombe Express)
Remembrance Day will look a little different this year for Lacombe

The Lacombe Legion is taking COVID-19 precautions for people who want to pay their respects.

Chad Carlson (left) Jarita Carlson and their two children Milo Carlson (left) and Lennon Carlson are dressing up as Ghostbusters for Halloween. (Alannah Page/Lacombe Express)
Lacombe family passionate about Halloween and giving back to their community

COVID-19 has changed how the Carlson’s will celebrate Halloween this year

The Lacombe Legion volunteers laid poppies beside the graves of veterans on Oct. 28. (Alannah Page/Lacombe Express)
Lacombe Legion volunteers lay poppies for fallen veterans

Twenty volunteers showed up on Wednesday to pay their respects and help out

There were 410 COVID-19 cases recorded in Alberta Wednesday. (File photo by The Associated Press)
Alberta records 410 new COVID-19 cases Wednesday

Central zone dropped to 160 active cases

Royal Alexandra Hospital front-line workers walk a picket line after walking off the job in a wildcat strike in Edmonton, on Monday, October 26, 2020. THE CANADIAN PRESS/Jason Franson
Alberta labour board orders health-care staff who walked off the job to go back to work

Finance Minister Travis Toews said in a news release that he was pleased with the labour board’s decision

Pilots Ilona Carter and Jim Gray of iRecover Treatment Centres, in front of his company’s aircraft, based at Ponoka’s airport. (Perry Wilson/Submitted)
95-year-old Ilona Carter flies again

Takes to the skies over Ponoka

Children’s backpacks and shoes are seen at a daycare in Langley, B.C., on Tuesday May 29, 2018. Alberta Children’s Services Minister Rebecca Schulz says the province plans to bring in a new way of licensing and monitoring child-care facilities. THE CANADIAN PRESS/Darryl Dyck
Alberta proposes legislation to change rules on child-care spaces

Record-keeping, traditionally done on paper, would be allowed digitally

Prime Minister Justin Trudeau shakes hands with US Vice-President Joe Biden on Parliament Hill in Ottawa on Friday, December 9, 2016. THE CANADIAN PRESS/ Patrick Doyle
A Biden presidency could mean good news for Canadian environment policy: observers

Experts and observers say even a U.S. outside the Paris agreement may ultimately end up in the same place

People take a photo together during the opening night of Christmas Lights Across Canada, in Ottawa, on Wednesday, Dec. 4, 2019. The likelihood that most Canadians will enjoy a holly jolly Christmas season of gatherings, caroling and travel is unlikely, say public health experts who encourage those who revel in holiday traditions to accept more sacrifices ahead. THE CANADIAN PRESS/Justin Tang
Ho, ho, no: Experts advise preparing for a scaled-back COVID holiday season

Many of the holiday season’s highlights have already been scrapped or are unlikely to take place

Sen. Kim Pate is shown in Toronto in an October 15, 2013, file photo. The parliamentary budget office says a proposed law that would give judges discretion on whether to apply a lesser sentence for murder could save the federal government $8.3 million per year. THE CANADIAN PRESS/Colin Perkel
Judicial discretion for mandatory minimum sentences for murder would save $8.3M: PBO

The result would be fewer people in long-term custody at federal correctional institutions, experts say

Husky Energy logo is shown at the company’s annual meeting in Calgary on May 5, 2017. THE CANADIAN PRESS/Jeff McIntosh
Husky pipeline spills 900,000 litres of produced water in northwestern Alberta

The energy regulator says environmental contractors are at the site

A raccoon paid a visit to a Toronto Tim Hortons on Oct. 22, 2020. (shecallsmedrew/Twitter)
Who are you calling a trash panda? Raccoon takes a shift at Toronto Tim Hortons

Tim Hortons said animal control was called as soon they saw the surprise visitor

Most Read