Is the Yellowstone Supervolcano Dangerous?

What Would Happen if the Supervolcano, Yellowstone Erupted?

Yellowstone is a national park located in Wyoming, United States and spans 3,472 square miles (8,987 square kilometers).  The volcano is actually the entire park region, which is why it is not physically visible by a visitor in the park.  The Yellowstone supervolcano is scary, no doubt, and monstrously dangerous! And yes, it would kill a lot of people if it erupted and cause many other problems for many more people. Past eruptions have measured an estimated eruption of more than 250 cubic miles of magma.  Ultimately, the Yellowstone eruption would affect the entire world.  The USGS has an entire glossary on the Yellowstone supervolcano; however, we’ll cover the most important parts of this report here.  A supervolcano is a volcano that possesses the eruption power of magnitude 8 on the Volcano Explosivity Index (VEI).  This means the eruption would be greater than 240 cubic miles (1,000 cubic kilometers). 


Analyzing Past Yellowstone Supervolcano Eruptions

To human knowledge, Yellowstone has erupted three times. The first eruption was discovered to be approximately 2.1 million years ago, the second roughly 1.2 million years ago and most recently, 640,000 years ago. Past eruptions usually lead to the resulting eruption area collapsing upon itself, leaving a massive sunken crater (also called a caldera) which for Yellowstone last time was around 1,500 square miles. Given Wyoming’s position in the United states, geographically, that’s bad news for a lot of surrounding people. 

This is considered an active supervolcano and recent rumors have been floating around about an upcoming eruption.  And the truth is, the supervolcano could erupt at any time. Those directly near the volcano will not survive the immediate threats. Everyone else will suffer from a variety of sub effects…byproducts from the volcano. Although the supervolcano eruption will not cause a mass extinction, it is certain to be an extremely damaging event which will take the life of an estimated 87,000 people, instantly.

The Yellowstone Eruption Debris and Climate Change

A supervolcano eruption means bad news for the climate and surrounding environment, especially the air.  Contamination would be everywhere, and the entire North American continent would be covered in an intense blanket of ash, most thick towards the center of the eruption and thinning outward. The heavy ash debris in the air will block out the sun and pollute the water supplies.  Do not drink ash-infected water, it is poisonous.  A lot of people will die from lack of water alone.

Part of the reason for all of the rising anxiety lately surrounding Yellowstone, comes down to the frequent earthquakes the national park has been suffering. Recently, Yellowstone even suffered a 4.8 magnitude quake (in 2014).  Usually the earthquakes that Yellowstone braces for are much less severe and very non-threatening.  Researchers argue the increased frequency of quakes will not only affect the sensitive integrity of the supervolcano, however, could quite possibly be a warning sign that the massive, lava-spewing killing machine is about to explode for a fourth time.  The most recent 4.8 magnitude earthquake has caused ground uplift, which is basically a term that describes the ground physically lifting in certain regions due to seismic activity. This is a big deal and many scientists who study Yellowstone see a cause to fear this recent change.  Think about it: thousands of years go by without any ground uplift and now all of a sudden we have huge quakes and ground shifts of a noticeable significance.  In fact, in some areas the ground has lifted almost an entire foot (10 inches to be exact). This is a problem and the exact reason many scientists believe this could mean we are closer to the fourth catastrophic supervolcano eruption of Yellowstone.  Some of the same researchers suggest that the animals in the area are onto the change and have been responding differently, more cautiously.  Traditionally dogs and other animals (bison, etc) are known to be able to detect the seismic activity and volcano activity beforehand, almost as if they were nature’s natural warning whistle.   There are currently an estimated three thousand earthquakes in the Yellowstone region each year (this number is going up).

The debris arising from a Yellowstone supervolcano eruption would be dramatic and devastating, ultimately to the entire United States.  Not only would a full eruption be more than a thousand times the 1980 Mount St Helens eruption…however, volcanic ash debris would spray into the air, up to 25 miles high.  To be clear, the entire northwest US would be demolished and unlivable with a ridiculously high mortality rate.  In fact, an estimated two thirds of the US would become unlivable.  A Yellowstone supervolcano eruption would, in itself be astronomically powerful and those in the United States who did survive the immediate threats (those who do not live in the northwest), will suffer a major food deficiency as much of the food production in the United States is located in the northwestern states.  An additional side effect will be cooler weather, with perhaps as much as 25 degrees cooler weather on a global scale as a result of the sulfurous gas (also known as aerosols) that effectively blocks the sunlight. This post-eruption period is often referred to as a “volcanic winter”. 

It is important to observe and recognize the signs.  Relying upon the government systems to alert of a catastrophe is outrageous considering the government has an ulterior motive of keeping the peace and people calm.  If the people knew that Yellowstone was going to erupt, there would be mass panic and evacuation.  Evacuation and mass panic may be considered a rash response in the government’s eyes (though these actions are completely warranted and more than reasonable when a supervolcano is about to explode in your backyard). Mass hysteria will greatly harm the economy and political structure, among other complications, and because of this, it is reasonable to assume the government warning systems cannot be relied upon.  The life of the citizens is what is actually on the line here, the citizens themselves should be informed and take the proper precautions; this may include families having to relocate in order to save their own lives.  Yellowstone is a real threat, which has been proven to erupt before, several times and in spectacular fashion. It needs to be taken seriously and prepping for a Yellowstone supervolcano eruption is essential to surviving the potential cataclysms of the world.

This threat is more than just a winter long.  Some researchers and studies have suggested that this thick blanket of ash will linger in the atmosphere, worldwide, for more than a decade.  This ash literally changes the chemical composition of the Earth’s atmosphere for the time it remains in the air.  The ash also prevents the vegetation from growing, and it takes roughly a decade or more of rain to clear the land so vegetation can grow again.  

How to survive the Yellowstone Supervolcano Eruption

It’s best to be prepared no matter what.  One survey suggested that the odds of this supervolcano erupting in your lifetime are 1 in 10,000, the same odds that a person would get struck by lightning.  However, people do get struck by lightning and we know already that Yellowstone has erupted, three times at least, and that one of those times happened roughly 600,000 years apart. We are currently 640,000 years from the last eruption, and can assume we are in the suspected eruption pattern.  Being prepared is essential.  Living within the Yellowstone Eruption Zone (YEZ) is a death trap, which is roughly 1500 square miles surrounding the park.  Immediate evacuation is necessary for anyone living within the YEZ. Living outside of the YEZ, but still within the United States or on the North American continent, means risk and a fallout shelter is the only sure way to survive the immediate aftermath of a Yellowstone eruption.  Even states bordering the Yellowstone Eruption Zone, would want to consider evacuating to avoid the heaviest downpours of ash.

Picking a place to live which has historically been completely demolished by nature, repeatedly, seems like a bad plan. Due to the nature of the threats Yellowstone’s supervolcanic eruption would produce and the powerful magnitude of its destruction, anyone living within the immediate Eruption Zone, would be wise to relocate immediately and build a life somewhere safer.  There are scientists who regularly monitor Yellowstone for important and threatening changes, however, ultimately the government is responsible for notifying the public, which is not acceptable when the lives of thousands of people is at immediate risk. The people need to wake up and review the increased seismic activity, and the developing ground uplift.  It is more than reasonable for the people who live near an active supervolcano (even the close neighbors), to be worried.  Building an underground shelter (a fallout or bomb style shelter), is a very wise decision on land which is located outside of the expected eruption zone (to avoid the rolling magma). The farther away from the eruption zone, the cleaner the air will be and easier survival will become.  Considering the air will be troublesome for more than a decade, the shelter must be outfit with the appropriate mechanisms to survive secluded living for both: a decade or more, and for surviving the aftermath of a supervolcano eruption specifically. Respirators and chemical suits are imperative and should be a part of all emergency bags to survive the immediate dangers and allow mobility.  Click here to view our complete guide on how to build an underground fallout shelter.


Many scientists who study Yellowstone suggest there would be ample notice developing as Yellowstone is preparing to erupt; some believing there would be signs weeks ahead of time, others believe signs would appear even years in advance.  Regardless, it is important to prepare as it is definitely sure to erupt again, and very well could happen soon.  History and science tells us that the Yellowstone supervolcano WILL erupt again, it is just a matter of when.  The Yellowstone threats are increasing in recent times, so the best plan for a United States citizen, no matter their geographical location, is to be prepared! Two words: Raining Ash. 

Tags: how to survive the Yellowstone supervolcano, surviving a supervolcano eruption, will Yellowstone supervolcano erupt, is Yellowstone dangerous, how many people would an erupting Yellowstone supervolcano kill

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