March 23, 2013
Posted by Austin Elliott
This is the inaugural post of a weekly series I promised to start that will supplement my more in depth but sporadic blogging about topical seismic events. A couple months ago I joined Twitter to broadcast some of the interesting seismic news snippets I come across daily, including lots of content that didn’t really warrant drawn out posts. As I promised then, I’m now compiling my full week of Tweeted links into a “weekend reading” sort of post, to let you catch up on all the earthquake news you missed as it flew by on Twitter. So here goes: a bunch of articles about earthquakes to read, and why to read them.
Earthquake Early Warning
The biggest U.S. quake news was the tremor that rattled L.A. a couple weeks ago and spawned renewed lamentations about the stagnant state of California’s earthquake early warning system. The New York Times had the most comprehensive story:
…but some local media outlets had their own lamentations to add:
To me the highlight of the New York Times piece was the imaginative explanation of what benefits early warning of an earthquake could provide:
“[Japan’s EEW system was able to] activate computerized programs to slow commuter trains so they did not go off their tracks, stop elevators so passengers were not stranded between floors, flash highway warning signs instructing motorists to slow down and avoid overpasses, and open doors at fire stations so they would not be stuck shut should power be lost.
The warning would go out to home computers and personal cellphones, giving surgeons a moment to withdraw scalpels, workers at Disneyland time to shut down Space Mountain, home cooks an opportunity to turn off the gas and everyone a moment to… dive under a desk.
If you are cooking, you can step away from the boiling water… it would help people psychologically, decreasing the surprise that can freeze people in confusion and fear when the ground starts moving, or lead to panicked and dangerous reactions, like running outside a building.”
I like the introduction of the intangible psychological benefits of reducing the paralyzing suddenness with which earthquakes set upon us.
A bunch of articles have just come out regarding earthquake survival kits.
Oregon Live asks where to put them (the answer is “everywhere… and make sure they’re accessible”).
The USA Today introduces us to some particularly dedicated preppers:
And the New Zealand Herald describes an effect I think most seismologists would be ecstatic to learn of: small tremors have a huge impact on emergency kit sales (up 300%), signaling that people really do treat the benign moderate jolts as reminders of real hazard.
Prediction vs. Mitigation
On a subject intimately related to the prior two, The Guardian published an article by Dave Petley, director of the Institute of Hazard, Risk, and Resilience at the University of Durham (and perhaps known more familiarly as the author of AGU’s Landslide Blog). Dave presents the elusive ideal of earthquake prediction through a simple and plainspoken set of thought exercises, which ultimately illustrate that prediction isn’t truly what we want. Mitigation, preparation, and a few moments warning should suffice… and may have to.
On the 2nd anniversary of the March 11, 2011 M9.0 Tohoku earthquake, the National Oceanic and Atmospheric Administration reminded us that twenty eight other tsunamis have struck various parts of the world since then.
Earthquakes Rock the Atmosphere
A widely circulated research result this past week was the discovery of significant signals from the Tohoku earthquake… recorded by satellite gravity measurements as pressure waves passed through the edge of the atmosphere. There’s a great animation of the data here:
That should do it for now. Tune in again next weekend, or Follow me on Twitter! @TTremblingEarth
I’m a big supporter of earthquake early warning systems, but I have to admit that having people get the right psychological response after hearing an alert enters the realm of social psychology. We live in a world where we are constantly surrounded by alert noises – people’s SMS text tones, pop ups from computer windows and such are an every part of daily life. Getting a loud buzzing noise is not necessarily intuitive enough to get people to take the correct action. Japan now utilizes several EEW alert sounds, including one for the television (the bell chime heard on NHK), a triplet wail (used by the Real-Time Earthquake Information Consortium and adopted by a few of the EEW signalling manufacturers) and a cell phone alert tone. Confusing to say the least! Ultimately, I think the alerts must be paired with voice instructions on what to do (which many EEW signal devices do in Japan)and not just shout “EARTHQUAKE! EARTHQUAKE!” because otherwise we end up with a bystander-effect type of situation where everyone just looks at each other for guidance. People need to be told specifically “DROP, COVER AND HOLD ON UNTIL THE SHAKING STOPS” otherwise the alert will probably just have them run when the shaking finally starts.
At the end of the day though, the benefits of EEW in California probably won’t be fully realized for many years even after it is in place because the biggest benefits would be automation of systems which will cost much more for the end-users. It’s been almost 6 years after the Japanese EEW system was put into place and many places still lack receivers for the alerts (even the J-ALERT public address system is unreliable in some areas). For California and the Pacific Northwest, a more immediate benefit, I personally think, lies with tsunami early warning and utilization of Urban Search and Rescue resources. As it stands, the earthquake information email bulletins the USGS sends out usually take 30 minutes to an hour, which is a lot of time lost of you’re talking about deploying a USAR team. (I’m not sure what the Shakecast USGS program is like though, might have a shorter delay.) Even without tidal gauges and tsunami buoys, we could already be on an alert for a major tsunami if the initial EEW projection is of a certain magnitude (I think the WeatherNews version of their EEW software in Japan does this automatically if the projected hypocenter is in the sea and the magnitude is >6). I think this in particular could make a significant difference if we had a Cascadia subduction zone event. These two particular things are rarely mentioned in the press but I think they are probably much more tangible in benefit (at least sooner after EEW is implemented) than some of the other things people are hoping for.
I totally agree: the efficacy of a warning system will depend highly on input from social psychology on implementation methods… and the system will take a long time to be robust and ubiquitous. It’s obviously hugely important to have the detection and dissemination infrastructure in place, and that’s what scientists/the government are closest to in California. It’s rather intriguing and stimulating to consider what could be done with that sort of information, and how it would be implemented. That will be a much longer term project, and may define a sort of social seismology in the next few decades as early warning systems become more pervasive.
Tsunami warning systems are a good place to focus, but also to look for guidance. Tornado warning sirens may be another, since alert sounds and activation policies vary by county, but there’s generally little confusion about what to do–sign of a good public education campaign.