4 March 2019
California is volcano country
Posted by Jessica Ball
One of the big projects I’ve been working on for the past couple of years has been assisting my SIC (Scientist-In-Charge) at the California Volcano Observatory in writing a report about California’s exposure to volcanic hazards. And (not) coincidentally, that’s the title of a new report that the USGS just released last week!
We’re very proud of this report, because it not only describes California’s hazardous volcanoes and the dangerous phenomena they could produce, but also puts them into a “why should we care” context. Volcanic unrest in California could have an interesting combination of impacts. For one, we have 8 moderate-to-high-threat volcanoes that could become active. Based on the record of volcanism over the last few millennia, the probability of a small-to-moderate-sized eruption occurring in California in the next 30 years (16%) is similar to the 30-year forecast for a magnitude 6.7 or greater earthquake on the San Andreas Fault in the San Francisco Bay area (22%). So, there are places all over the state that could be impacted: three of California’s volcanic areas are in the northern part of the state, one in the south, three areas in the east-central and one is within 100 miles of the Bay Area.
Second, the variety of impacts is wide, and they have the potential to be far-reaching in both time and space. For example, explosive volcanic eruptions that produce a lot of ash could impact air traffic routes in some pretty busy areas – up to 2,000 aircraft pass through volcanic hazard zones in California daily. As you may know, volcanic ash (which is mostly ground-up glass and crystals) does not play well with hot plane engines and clear windshields. Not to mention that ash from eruptions in the Lassen volcanic region, for example, has traveled as far away as Nevada – so we might expose other states to volcanic impacts!
Why is a report like this one useful? First, it contains basic information about the volcanoes and hazards in question, which helps people involved in disaster response – such as emergency and land managers, civil defense organizations, and first responders – realize just what they might be up against in future volcanic unrest. Second, it contains vulnerability information about people, critical infrastructure, and other resources that the USGS and its partners can use to plan for the next California eruption.
We’re also taking a bigger step into the realm of vulnerability research by looking at California’s exposure to volcanic hazards. Exposure has a very specific definition when talking about hazards – it refers to people, property, and infrastructure at risk to volcanic phenomena. “California’s Exposure to Volcanic Hazards” compiles geographic information about who and what is located in California’s volcanic hazard zones and analyzes it based on a number of different geographical factors, from state totals down to county and local concerns. And, all the data are included with the report for USGS partners to do more detailed vulnerability and threat analyses. It’s a direction that we’re starting to go with our volcanic hazard assessments, because our partners aren’t just interested in what might happen – they also need information about who and what it will happen to, when and how fast and how far hazards might go, and where the most heavily affected regions might be.
It’s important to remember that all of this information isn’t meant to be fear-mongering, but rather to help people prepare for volcanic unrest in the event that it happens. These volcanoes and hazards already existed and the information has always been freely available through the USGS, it just hasn’t been encapsulated in this form before. Hopefully our new report will prompt decision-makers to do more in-depth vulnerability analysis and hazard mitigation planning in the future, and provide residents of California with some useful information for their own personal safety planning.
Check out the full-length report for all the details here: http://pubs.er.usgs.gov/publication/sir20185159
- A little AP News clip of me pointing scientifically while describing the report: https://apnews.com/c424d8734d5b4728afeca6bfffbdd0d1
- Robin Andrews’ Forbes article: 200,000 People Go Into California’s Volcanic Hazard Zones Every Day
- LA Times: https://www.latimes.com/local/lanow/la-me-ln-state-volcanic-hazards-20190225-story.html
Does this hazard report take into consideration the contamination of water distribution systems in California by volcanic products?