Molten Monitoring: How Cal OES Tracks Local Volcanos


While often overshadowed by the seismic activity associated with fault lines, California is home to several volcanos that demand careful monitoring. The California Office of Emergency Services (Cal OES) plays a crucial role in keeping a watchful eye on these dormant giants, ensuring the safety and preparedness of communities across the state.

While many of California’s volcanos are dormant, their potential for activity poses a risk that cannot be ignored. See a list of volcanos in California.

Volcanos in California

Volcanic eruptions in the state are not currently imminent, but in addition to fires, floods, earthquakes, and tsunamis, Cal OES’ Seismic Hazards Branch monitors any possible volcanic threats from the eight volcanic areas classified as moderate, high, and very high threat in the state.

Volcanic eruptions and earthquakes are a way for Earth to release pressure and heat, much like a safety valve. A volcano is basically a vent, or opening, in the earth’s crust from which hot molten rock, gases, and volcanic ash escape to the surface.

Prepare your Home and Family

Preparing your family for a possible volcanic eruption will not only help protect your health and property, but also may be the difference between life and death. Below are steps you can take to minimize impacts to your family and home in the event of volcanic eruption:

  1. Know where the active volcanos are in your area and how close you are to them.
  2. Consider anyone with functional and/or access needs, children, pets, and livestock.
  3. Create an emergency evacuation plan with your family. Review it often so that each person knows what to do, how to find each another if you’re apart, and how to contact neighbors and/or emergency services if you cannot get away from the property using your own transportation.
  4. Create an emergency kit for your car including maps, tools, a first aid kit, a fire extinguisher, flares, additional non-perishable food, booster cables, sleeping bags and/or emergency blankets, and a flashlight.
  5. If there are disaster warning sirens in your area be aware of what they sound like. When a volcanic eruption occurs, you’ll want and need to listen for them.
  6. Know how to turn off all utilities.
  7. Obtain proper respiratory protection such as an air purifying respirator, also referred to as an N-95 disposable respirator.
  8. Review your homeowner’s insurance policy, and if necessary, increase your level of coverage to ensure you are covered adequately.

To learn more about our local volcanos and other tools and resources available, visit the Cal OES Seismic Hazards Branch page here.