Living near geographic wonders like Yellowstone National Park provides beautiful vistas, challenging hiking, and a sense of awe. It also makes you wonder what risks come with living close to one of the world's largest dormant volcanoes, and massive geyser basins. 

Read on to learn how to keep your family safe in case a volcanic eruption ever happens. 

Source: Nicolasintravel on Unsplash

Summary: How Likely is a Volcanic Eruption? 

Scientists estimate that the supervolcano underneath Yellowstone National Park hasn't erupted for over 600,000 years. Despite that, it's one of the largest volcanoes in the world. 

It is incredibly active. Researchers closely watch its magma chamber, which is the lake of molten rock underground, inside the volcano. They also watch for hydrothermal (superheated water) explosions, which can happen with no warning. 

In short - we're not completely sure when the Yellowstone Volcano will erupt. But we know that when it does, it's capable of spewing up to 240 cubic miles worth of magma, rock, and ash in a single eruption and will definitely cause massive ground deformation. That's enough material to completely flatten the area for miles around, sending ashfalls across nearby states, causing parts of the ground to collapse in unexpected areas, and even affecting the global climate. 

Source: Mandy Beerley on Unsplash

How to Prepare for a Yellowstone Volcano Explosion 

Each supervolcano across the world is watched carefully for activity. The U.S. Geological Survey (USGS) has a volcano notification system to monitor the volcanoes that are at greatest risk to erupt, such as tracking background volcano hazards and to notify those in surrounding areas.

Despite this, sometimes volcanoes erupt with very little warning. Earthquakes and magma flow can come and go for years without an eruption. This makes people relax - sometimes a little too much. 

Essential Supplies 

It's important to be prepared for a wide variety of emergencies. 

• Make sure you have emergency food and water stored
  
  
• Know multiple evacuation routes (more on that below)
  
  
• Have an emergency evacuation kit
  
  
• Prepare gas masks and air filters for each family member
  
  
• Don't forget child-sized masks if necessary
  
  

Since eruptions can happen quickly, there might already be smoke and ash in the air. The smoke from a volcano has small particles of ash in it which are dangerous to breathe. It’s especially dangerous for people with asthma or breathing problems.  It's important to protect your lungs as your family escapes to a safe location. 

Source: MIRA Safety

Just like a wildfire, hurricane, or flood escape plan, you need an emergency kit or "Go Bag". This should contain important items like:

• Nonperishable food
  
  
• Prescription and over the counter medications
  
  
• Chargers
  
  
• Flashlights & batteries
  
  
• Radio
  
  
• Copies of important documents

Tip: for a complete guide on how to pack a go bag, check out our article here.

Preparing Evacuation Routes 

Many places have evacuation routes marked with signs. These are helpful because they have already been ruled as "safe" by local authorities. 

They might still become blocked by lava flow or mudslides. Or the roads might be blocked with people trying to get out. 

It's a good idea to have multiple escape routes planned ahead of time. Practice evacuation drills with your family. Make sure everyone knows what to do. 

Evacuation preparation saves lives. In 2008, over 12,000 people were evacuated from a small town in Columbia when the local Geological Survey detected mud and lava flow along with a 50,000-foot ash column from a nearby volcano. The evacuation was accomplished overnight and there were no fatalities from the volcano. 

Source: Jake Espedido on Unsplash

Quick Tips for Escaping Volcanos 

Everyone has seen pictures and videos of intense lava flows after an eruption. There are many other threats though, including mudflows, superheated water, earthquakes, and polluted air. 

When escaping a volcanic system, keep a few guidelines in mind: 

• Stay upwind. Wind will blow ash downwind, so travel in the opposite direction.
  
  
• Stay away from rivers or creeks that are flowing downhill. These will quickly be clogged with mud, ash, and liquid rock.
  
  
• Stay in your car with the windows up if possible. This will protect you from ash and smog.
  
  
• If you must go outside, wear a properly-fitting mask with a filter. In a pinch, you can tie a wet cloth over your nose and mouth.
  
  
• Pay attention to early warning and evacuation systems. You can't outrun or outdrive lava flow, so it's important to get as far away from it as possible early on. 

Overview: History of Yellowstone

Yellowstone is famous for its beauty and strange areas of heat and smoke. Indigenous Americans have many oral histories about the region. European-American explorers in the early 1800s were so amazed by the intense geological activity that people back East actually didn't believe their reports!  Scientists eventually classified Yellowstone as a volcano. 

Source: USGS

In fact, a supervolcano lies beneath the park, one that erupted almost half a million years ago. A volcano gets that ranking by having evidence of a past volcanic eruption that ranks an 8 or higher on the Volcanic Explosivity Index (VEI). This measures the amount of material released in an eruption. Higher numbers mean a greater amount of lava and ash. In the case of Yellowstone, it could release over 200 cubic miles of superheated rock.

What's the Difference Between Magma and Lava?

You'll often hear that the scientists studying Yellowstone are keeping an eye on the magma well. When the superheated molten rock is underground, it's called magma. When it erupts and flows above-ground, it's called lava. 

Historic Eruption at Yellowstone 

This "supereruption" happened around 630,000 years ago. According to scientists, there was a smaller eruption about 70,000 years ago. This means that the Yellowstone supervolcano is considered "dormant," or not currently active.

Don't let that fool you though - there's a lot of hydrothermal activity at Yellowstone, which creates its famous tourist attractions like geysers and hot springs. 

Source: Noémie Cauchon on Unsplash

Geological Background 

Even though there hasn't been an eruption in the Yellowstone hotspot for thousands of years, there is still a lot of fascinating geologic activity. 

Magma Rivers

An underground river of molten rock called magma has slowly drifted across the American West for millions of years. This has created "hot spots" of underground magma around Yellowstone National Park. These spots create interesting tourist sites. 

For example, visitors can view a Yellowstone caldera. These look a bit like lakes or ponds. But they are actually evidence of volcanic activity. Magma bubbles up under the ground, forming a lump. When the volcano erupts, all the magma flows out and the lump collapses inward. This leaves a shallow basin that eventually fills up with rainwater. 

Superheated Water 

All that heat means that much of the groundwater in Yellowstone is superheated. This creates favorite features like the Old Faithful geyser. The heated water becomes squeezed underground and must burst every so often to relieve the pressure.

During the eruption of the Yellowstone, superheated water and rock could create explosions similar to the effects of bombs. 

Source:  Emily Campbell on Unsplash

Eruption Warning Signs

Just like scientists can monitor weather systems to tell when a hurricane is coming, volcanic eruptions give warning signs. 

Small earthquakes are often one of the most noticeable signs. Local water sources and the ground itself will often get warmer. These are all warnings of the heated pressure getting ready to explode just beneath the surface. 

Eruption warning signs include:

• Steam eruptions
• Heated water
• Chemical changes in local water
• Heated ground 
• Deformed ground, like small swellings in the ground 
• Earthquakes

The famous Mt. St. Helens eruption had many dramatic warning signs. After years of lying dormant, a huge earthquake in 1980 signaled that the volcano was waking up. Large bulges of lava in the mountain, steam eruptions, and cracks in the mountain's surface hinted that magma was slowly climbing up the mountain's surface and ready to erupt. This gave people time to evacuate. 

Source: Mt. St. Helens Science and Learning Center

A big problem is that volcanoes can present these signs for decades before any eruption actually happens. People living in close proximity to a volcano may become too relaxed and not prepare enough for a volcano finally erupting.

Effects of Volcanic Explosions

The immediate effects of an eruption are catastrophic. Plants, buildings, and landscapes are quickly covered with lava and ash. Volcanic eruptions often trigger mudslides, which can shear off the sides of mountains and hills and destroy anything caught in their wake.

Rivers, lakes, and streams quickly become clogged with ash, mud, and rock. Sometimes they overflow their banks, causing even more damage. 

What's a "Pyroclastic Flow?" 

The immediate effect of an eruption is called the pyroclastic flow. This is what we picture when we think of a lava flow. These move extremely fast - often over 200 miles per hour. They annihilate everything in their path and you can't outdrive them if you're nearby. This is why early evacuation is so important. 

Global and Local Effects 

The 1912 Novarupta eruption in Alaska is a good example of a major eruption with global effects. In fact, it was one of the 5 largest volcanic eruptions in recorded history. 

The ash cloud created was so large that it caused a cold summer across the region. The ash from the eruption eventually encircled the entire Earth. 

The local effects were even more disastrous. Local communities were wiped out. The terrain was permanently changed. 

It's important to remember that any region with volcanic activity is a living, changing environment. Experts can't always predict how the geography and volcanic activity will change over time.  

Source:  Yosh Ginsu on Unsplash

Monitoring & Research at Yellowstone National Park

Scientists continually monitor seismic activity in the Yellowstone national park region to detect possible eruptions. The Yellowstone Volcano Observatory (YVO) has a sophisticated monitoring system across the region. It incorporates academic, federal, and state agencies who all work together to monitor and report on dangerous activity. This includes potential earthquakes (seismic activity), superheated water (hydrothermal events), and of course, volcanic activity. 

2024 Biscuit Basin Explosion 

In fact, tourist locations around Yellowstone are periodically closed because of elevated activity.  As of Summer 2024, Biscuit Basin was closed for the season because of a hydrothermal explosion on July 23. 

Source: National Park Service 

The monitoring organizations are actively updating and improving their monitoring equipment because of events like this. While the technology is advancing, the intense hydrothermal activity around Yellowstone can often make it hard to get accurate data out of the instruments. 

Emergency Responses 

Lava flow can destroy property and cause millions of dollars worth of damage. Eruptions often take months to complete. For example, the 2021 eruption of La Palma in the Canary Islands lasted from September through December of that year. 

What this means for emergency preparedness is that you may not be able to return to your home very quickly after evacuating. Your Family Emergency Action Plan (read more on how to create one from scratch here) should include a long-term evacuation plan. 

A few tips to consider:

• Know all the evacuation routes out of your neighborhood, town, and region.
• Have a local and a distant evacuation destination. You might have to stay there for several months.
• Make sure you have copies of all important documents in case you can't return home quickly. 
• Know the locations of local emergency shelters.
• Practice your evacuation plan starting from multiple locations - home, school, work, the gym, etc.

First responders set up areas called "exclusion zones" after an eruption. In the case of a Yellowstone eruption, this would include surrounding areas. These are regions where the public is not permitted because it may not be safe. Keep in mind that your home, evacuation route, or even your emergency destination might end up inside of an exclusion zone. That's why it's a good idea to have multiple options and have copies of all crucial identification and paperwork in your go-bag. 

What you Can Do to Get Ready for Volcanic Activity Now  

Steps you can take to prepare your family today:

• Check for a volcano notification service app in your area 
• Know warning signs and be aware for small earthquakes and ash fall 
• Practice following several different evacuation routes 
• Have a go bag ready complete with masks and filters

If you live in a high-threat area with lots of earthquake activity or where eruptions have occurred, always remember that you might have far less time to prepare than you think you will. Thinking ahead is key. Consider equipping yourself with MIRA Safety gas masks and filters to stay safe from smoke, ash, and harmful particles in the event of a volcanic eruption.