Volcanic eruptions are more than juicy fodder for middle-school science fair projects. When hot gasses and molten rock spew from openings in the earth, it can quickly alter landscapes, level buildings, and kill a lot of people. Just ask the citizens of ancient Pompeii (if you can find anyone.)
Volcanic eruptions run the gamut in terms of severity, from piddly “effusive eruptions,” in which streams of molten rock flow from a volcano, to the massive “explosive eruptions” of supervolcanos. The former happens all the time, whereas the latter are, thankfully, very rare, as one occurring could result in planet-wide catastrophe.
How much do you need to worry about a volcano destroying your life? It depends on how much you want to worry, I guess. Most people in the United States are unlikely to have to contend with the immediate effects of a volcanic eruption (unless they live in the “ring of fire”; more on that in a few paragraphs), but a large enough volcanic eruption anywhere on the planet could lead to dire consequences for basically everyone.
Supervolcanos: Catastrophic natural monstrosities
The worst-case-scenario when it comes to volcanoes is a supereruption of a supervolcano. We’ve identified 60 supereruptions in Earth’s history, and there are about 20 supervolcanos on the planet. The largest supereruption ever in North America was at Yellowstone (arguably the largest volcano on earth) about 2.1 million years ago. The most recent supereruption was in Taupo in New Zealand around 22,600 years ago. So, not exactly a regular occurrence.
How inconvenienced would you be if a supervolcano erupted tomorrow?
Very. A huge volcanic eruption is like winning the bad luck lottery: The chances of it happening are very low, but the ill effects would be gargantuan. If, say, Yellowstone, erupted massively, the area for maybe 40 miles around would be flooded with deadly, molten rock. Parts of Montana, Idaho, and Wyoming would be buried in toxic ash. The last time Yellowstone erupted (about 600,000 years ago) enough ash was expelled to bury a large city in kilometers of ash.
Dying instantly from a volcano-propelled rock smashing your head apart or suffocating in poisonous ash might be preferable to living in a post-supereruption world. The gunk expelled into the atmosphere would likely change the global climate for years or decades, bringing untold devastation, disruption, and misery to billions.
The “little ice age” between around 1300 and 1860 was probably caused (at least in part) by volcanic activity and it resulted in hundreds of years of colder, longer winters, widespread famine, mass fish die-offs, and other unpleasantness. And that wasn’t even a supereruption.
Luckily, you’ll probably die of heart disease before you have to worry about the after effects of a volcanic supereruption—but you never know. Assuming we’re actually monitoring them, if a supervolcano were to erupt, scientists think we’d have about a year’s warning to prepare and/or freak out.
The danger of smaller eruptions
The danger of supereruptions may be distant, but smaller scale eruptions are fairly common. About 50-70 volcanoes erupt every year on average, and around 278,000 people have died because of volcanos since 1500.
According to the CDC and countless middle school baking-soda-and-vinegar-based science presentations, volcanic eruptions can result in burn injuries, falls, car accidents caused by slippery and hazy driving conditions, floods, mudslides, power outages, drinking water contamination, and wildfires.
Even relatively small volcanic events can have widespread consequences, like the 2010 eruption of the Eyjafjallajokull volcano in Iceland that grounded more than 100,000 airline flights, stranding millions of passengers.
Hopefully, we’ll have a good amount of advanced warning for any major eruption—three months passed between the first signs of volcanic activity at Mt. St. Helen’s and its eventual eruption in 1980. If official warnings are heeded, and everyone acts cool, the chance of death and injury from a volcanic eruption is low. (It’s not like anyone would argue that volcanos aren’t real, or that standing in the way of a lava flow is an important expression of our constitutional freedoms, right?)
Learn a lesson from people who died because of volcanos
Some of the 57 people who died as a result of 1980 eruption of Mt St Helens were heroes, like volcanologist David A. Johnston, a who died doing what he loved best: Monitoring volcanoes and warning people to stay away from them. Some were just dopes, like Harry Randall Truman.
A bit of a folk hero in the days leading up to the eruption of Mt. St. Helens, 83 year-old Truman gave lots of media interviews where he proclaimed that he wasn’t going to leave his house no matter what so-called “scientists” said.
“My wife and I, we both vowed years and years ago that we’d never leave Spirit Lake. We loved it. It’s part of me, and I’m part of that (expletive) mountain,” Truman told National Geographic.
Truman literally became part of the (expletive) mountain when an avalanche of mud and snow caused by the erupting volcano buried him and his 16 cats. His remains were never found.
Longer-term preparation for a volcanic eruption
If you live near one of the active volcanoes in the “ring of fire” that extends from southern British Columbia, to Washington State, Oregon, and Northern California, or if you near volcanos in Hawaii, you can do the following now to be ready in the event of a volcanic emergency:
- Ask your local emergency management system for information about shelters, evacuations, and any local alert system.
- Put together an at-home emergency supply kit (you should do this anyway, for any potential disaster).
- Masks and goggles are very important. Have N95 disposable masks on hand (huh, where are you going to get those?).
- Run an emergency drill or two.
- Have access to multiple sources of information, including a battery powered NOAA radio, emails from the Volcano Notification System, and local news.
Check out ready.gov’s site for more in-depth information about volcano preparedness.
Understand volcano warning terms
There are four levels of alert for volcanos. Here’s what they mean.
- Normal: Everything is cool with your volcano.
- Advisory: Volcano is exhibiting signs of elevated unrest “above known background level.”
- Watch: It’s getting more serious. The volcano is exhibiting “heightened or escalating unrest with increased potential of eruption, timeframe uncertain.” Or: an eruption is “underway but poses limited hazards.”
- Warning: Hazardous eruption is imminent, underway, or suspected.
Check out the U.S. Geological Survey for a more in-depth understanding of our volcano warning system,
What to do if you are told to evacuate
The bulk of the official advice about dealing with an imminent volcanic eruptions boils down to “get away from the volcano safely.”
The long lead-time for volcano warning will hopefully give you enough time to evacuate, but you don’t want to just throw some clothes in a bag and hit the road. Check out the Center for Disease Control’s list of actions to take when you’ve been asked/ordered to evacuate. It lists essential items to take with you, steps to take, and more.
What to do during the actual evacuation
So you’ve got everything ready, the evacuation order has been given, and it’s time to head out. Here’s are the steps to take to make your evacuation as smooth as possible, according to the CDC.
- Take only essential items with you, including at least a 1-week supply of prescription medications.
- If you have time, turn off the gas, electricity, and water.
- Disconnect appliances to reduce the likelihood of electrical shock when power is restored.
- Make sure your automobile’s emergency kit is ready.
- Follow designated evacuation routes—others may be blocked—and expect heavy traffic and delays.
If you are told to shelter in place
You might be asked to stay in your home and see how things develop or to wait things out. Here’s how to do that safely, according to the CDC:
- Keep listening to your radio or television until you are told all is safe or you are told to evacuate. Local authorities may evacuate specific areas at greatest risk in your community.
- Close and lock all windows and outside doors.
- Turn off all heating and air conditioning systems and fans.
- Close the fireplace damper.
- Organize your emergency supplies and make sure household members know where the supplies are.
- Make sure the radio is working.
- Go to an interior room without windows that is above ground level.
- Bring your pets with you, and be sure to bring additional food and water supplies for them.
- It is ideal to have a hard-wired (non-portable) telephone in the room you select. Call your emergency contact—a friend or family member who does not live near the volcano—and have the phone available if you need to report a life-threatening condition. Remember that telephone equipment may be overwhelmed or damaged during an emergency.
If you are caught near an erupting volcano
If you ignored all warnings in order to get up close and personal with a volcano, there’s been some unexpected eruption, or you signed up for a volcano tour with a questionable company, you might find yourself near an actual erupting volcano. If so, things are really up in the air for you. These are some of the steps recommended by the U.S. Geological Survey, though, to increase your chances of surviving.
- Move AWAY from hazard zones to improve your chances for safety.
- You may be exposed to falling ash and volcanic rocks (tephra), lava flows, lahars, toxic volcanic gases, and avalanches of hot rock and gas (pyroclastic flows).
- In confined spaces (caves or hollows) on the volcano, volcanic gases can concentrate and be very hazardous.
- Your route to safety might be cut off by lahars (volcanic mudflows). If lahars are a threat, STAY OFF VALLEY FLOORS AND OUT OF LOW-LYING AREAS.
- Pay attention to closure signs; they can save your life.