Social media videos show how people react during an earthquake
Footage from the 2018 Anchorage earthquake shows that people react differently in public and private spaces.
After a major earthquake, social media feeds are often flooded with videos of rattling furniture, swaying lamps and startled people. Experts often advise that the safest action is to drop, cover and hold on when shaking starts. But in these chaotic moments, people can react unpredictably, putting themselves at risk.
A group of researchers is using social media videos and closed-circuit television (CCTV) footage to find out what people do when an earthquake strikes. The recordings, filmed during a magnitude-7.1 earthquake that struck near Anchorage, Alaska, in 2018 are helping the group figure out better ways of advising those in earthquake prone regions. This research was presented at the American Geophysical Union Fall 2021 meeting by Dare Baldwin, a psychologist at the University of Oregon working, with students and an interdisciplinary team at the U.S. Geological Survey (USGS).
Watching for reactions
The team used the videos to find out how people’s reactions are affected by the amount of shaking. This baseline is important for future investigations of how earthquake early warning systems influence behavior, says Baldwin. A similar study from the 2011 Christchurch earthquake found that no one captured in CCTV footage followed all “drop, cover and hold on” actions.
Baldwin and her colleagues determined where the Alaska videos were taken using metadata and openly available information. They matched these locations with the USGS ShakeMap to compare measured shaking intensity with what they saw in the videos. The team identified what people did in the moments during and just after the earthquake. They saw a variety of actions including evacuating, running around, freezing and taking cover.
People act differently in public
The researchers found clear differences in the type of actions taken in public (schools, courtrooms, and airports) versus private (houses, apartments) spaces. Reactions evolved as the earthquake progressed, but generally the “drop, cover and hold on” sequence was more common in public. In private, people more often took shelter in a door frame, which highlights that this antiquated advice is still reverberating through earthquake country.
Responses like checking on others took place in both settings. In private settings, adults’ responses were often delayed by searching for children. While in public, adults are generally close to their children and can act with them immediately, Baldwin says. But at home, they are often in a different room, and it can take up to a minute to find them.
Earthquake drills for all settings
“We think that earthquake early warning can give people crucial seconds of advanced preparation time to get down and under cover before shaking begins,” says Baldwin. She also says that continued education and outreach campaigns for a variety of physical and social settings — such as ShakeOut drills — will be critical to getting people to understand the best way to use those precious extra seconds and trust that the rest of their household knows what to do too.
The team plans to apply this method to other earthquakes and perform comprehensive modeling that considers a wide range of conditions to determine the best outcomes across a variety of earthquake experiences, Baldwin says.