Humans are an unknown in California's new earthquake warning system

"A warning is no good if you don't know what it means."
By Mark Kaufman  on 
Humans are an unknown in California's new earthquake warning system
A 1989 temblor collapsed buildings in San Francisco's Marina District. Credit: David L. ryan / Getty images

When a big earthquake struck Mexico City in September 2017, Allen Husker, a seismologist at the National Autonomous University of Mexico, ducked under his desk. The nearby temblor hit before the school's early warning alarm bells could even start blaring. But almost everyone else ran outside.

"I was one of the only people left in my office," Husker said. "There was a panic," he added, noting that it's dicey to race down stairs when the world is violently shaking.

The event illustrates the short-lived chaos that can ensue during temblors and the way different people — sometimes with vastly different understandings about earthquakes — react to the same shaking.

California, with its recently launched Earthquake Early Warning Program and long-anticipated ShakeAlert app, must also now reckon with the emotional, fickle, and sometimes stubborn component of the system — a system that has the potential to spare many lives.

"Unfortunately, you have to deal with humans beings and the way they’re wired," said Dennis Mileti, a social scientist and the former director of the Natural Hazards Center at the University of Colorado.

Now that ShakeAlert is out in the wild, when to alert humans of an imminent quake is of significant concern for two seismologists, Husker, of the National Autonomous University of Mexico, and Elizabeth Cochran, an observational seismologist at the United States Geological Survey (USGS). They published an article in the journal Science on Thursday, stressing that it's still largely unknown how people will react when they get a quake warning on their phone. This is expected, of course, because it's a brand new system.

"We don't have a lot of experience with this system," said Cochran. "There’s not a lot of social science research on what people might do."

"You have to deal with humans beings and the way they’re wired."

That must change, Husker said, inviting social scientists to give him a call. "All of a sudden seismologists have to talk to social scientists," emphasized Richard Allen, director of the Berkeley Seismological Laboratory who led the development of the MyShake app. Allen had no role in the Science article.

But social scientists do know a fair amount about disaster warnings generally, and it doesn't bode well for earthquake warning programs. When Americans are notified of an imminent disaster, be it a tornado, flash flood, or hurricane, they don't promptly react to it. Rather, they prefer to chat about it.

"People do not automatically respond to warnings," said Mileti, who also had no role in the Science article. "They hang out and talk it over with other people. People are social animals."

But this chatter, intended to confirm information, won't cut it for a quake warning. The whole point is a quake is imminently coming soon — in seconds or tens of seconds. And that's only half the message. "When you receive an alert you should expect to take action," said the USGS's Cochran.

And herein lies the present challenge: When should people be alerted? Cochran and Husker argue that governments should set expectations for people to take action when there's potential for ground shaking, but critically, not when the shaking is mild, non-damaging, or potentially imperceptible for some folks. With alerts for small quakes "you warn people that might not even notice the shaking at all," said Cochran. This takes the bite out of an alert, should the next quake be a devastating, historic temblor. You know, the one that's been missing for over a century; the one geologists expect to hit the Golden State hard, just as quakes have in the past.

Los Angeles recently wrangled with quake alerts. After a couple of large quakes (of 7.1 and 6.4 magnitudes) hit about 100 miles from LA this July, many Angelenos expressed frustration that they weren't alerted via the ShakeAlertLA app, even though the shaking was mild at that distance. Even so, the city lowered the threshold for alerts from an intensity of 4 to 3. An intensity of 3 means minor shaking, perhaps like a truck rumbling by your house. That might not be the greatest idea if the goal is to alert people only when potential damage may occur.

"It was already low to begin with, and now they’re setting it lower," said Husker.

Mashable Light Speed
Want more space and science stories in your inbox?
Sign up for Mashable's weekly Light Speed newsletter.
By signing up you agree to our Terms of Use and Privacy Policy.
Thanks for signing up!

A buzzing phone alert warning for a weak or non-existent quake could confuse people, and render them ill-prepared for future temblor alerts. "A warning is no good if you don't know what it means," said Mika McKinnon, a geophysicist and disaster researcher who had no role in the article.

But, warning of mild, non-threatening quakes can serve a different though immensely important purpose: to remind Californians they reside in the dead center of quake country.

Mashable Image
The San Andreas Fault in Central California. Credit: Getty Images / Lloyd Cluff
Mashable Image
A collapsed section on the Interstate 5 after the 1994 Northridge quake. Credit: Getty Images / Marc Solomon

There's a role for smaller alerts, said Berkeley's Allen. "To me, we need to have two different levels of alerts," he said. One would be the "you're in danger" alert. The other would just inform folks that some shaking will likely occur. "That's the plan," said Allen, though how to achieve it is still developing.

A two-tier alert system could potentially prove revolutionary for the public's education.

"It's a fantastic thing because it reminds you that you live in earthquake country," said McKinnon. "I fully expect there is going to be multiple levels, just as there is for every warning system."

"If you're not constantly drilling it's easy to forget what you're supposed to do," she added.

Or, what you're not supposed to do.

Following Mexico City's big 2017 quake, a moderate quake hit a week later that few people felt, but the city's early warning system gave people advanced warning anyway (the quake hit some 370 miles away). When the city's sirens started, some people sheltered, and some evacuated buildings (something common in Mexico), which are stressful activities that may have prompted fatal heart attacks, noted Cochran and Husker. But one person jumped from a window, injuring themselves.

"You don’t jump out a window," stressed Berkeley's Allen. Fortunately, there's evidence that during disasters, full born panic "usually involves few persons, is short-lived, and is not contagious." But there will almost certainly be some panic. "The answer is we need to educate people about what to do when you get a warning," said Allen.

It may sound awfully trite, but that's the reality. Without an agency like California's Office of Emergency Services to establish clear expectations, people may react irrationally to the alert. Or, they may be slow to react, said Mileti, the social scientist. "It calls for the need for elaborate education on this topic," he said.

That's a supreme undertaking. "Could you train 39 million people to respond like robots when they get a beep on their cell phone?" asked Mileti. No, he said, but you can make a big impression on millions of people. The state can drill quake alert responses in schools, which is undoubtedly a worthwhile future investment (what Golden State kid doesn't know to Drop, Cover, and Hold On?)

As for adults, research published this year found West Coast denizens are unaware of the significant threats they face, even if they live in serious earthquake country. Overall, humans are famously poor at assessing risk.

The only alternative for our species, then, is repeated, incessantly echoed messaging about what an alert means. Everyone knows Smokey Bear's message — thanks to 75 years of memorable, iconic government public service announcements.

Mashable Image
Major California faults. Credit: USGS

"Education here means familiarity with the warning signal and its realistic danger," said John Vidale, a seismologist and professor of earth sciences at the University of Southern California. "Given the devastation of bad earthquakes, the sooner we can tell the public the better."

Indeed, there are hurdles ahead with a still progressing app-based alert system. There will almost certainly be false alarms and too-late warnings, said Vidale. People might get confused while driving. But there's universal optimism about the program among experts I've spoken with.

"I’m really excited," said McKinnon. "I really am looking forward to us having more information about what’s going on."

"I’m thrilled the country is going to have it," said Mileti.

"I have ShakeAlert via the ShakeAlertLA and MyShake apps, which definitely feels like progress, and makes the world around me just a little safer," said Vidale.

Though humans may be fickle and ingrained in our ways, when the coming big quake strikes, after the alert we'll only have ourselves to count on.

"I trust myself and the public to act with common sense," said Vidale.

Mashable Image
Mark Kaufman

Mark is an award-winning journalist and the science editor at Mashable. After communicating science as a ranger with the National Park Service, he began a reporting career after seeing the extraordinary value in educating the public about the happenings in earth sciences, space, biodiversity, health, and beyond. 

You can reach Mark at [email protected].


Recommended For You
Here's why '3 Body Problem' is set in the UK
A shot of Piccadilly Circus in the UK from the show "3 Body Problem".


'3 Body Problem': What's the deal with everyone smoking?
A man sits in a chair smoking a cigarette.

'Dead Hot' review: A wild mystery thriller that blends murder and dancefloors
Vivian Oparah and Bilal Hasna in "Dead Hot".


More in Science




When is the last day to file taxes?
A person at their computer holding a note that reads "tax time."

Trending on Mashable
NYT Connections today: See hints and answers for March 28
A phone displaying the New York Times game 'Connections.'

Wordle today: Here's the answer and hints for March 28
a phone displaying Wordle

NYT's The Mini crossword answers for March 28
Closeup view of crossword puzzle clues

NYT Connections today: See hints and answers for March 27
A phone displaying the New York Times game 'Connections.'

The biggest stories of the day delivered to your inbox.
This newsletter may contain advertising, deals, or affiliate links. Subscribing to a newsletter indicates your consent to our Terms of Use and Privacy Policy. You may unsubscribe from the newsletters at any time.
Thanks for signing up. See you at your inbox!