Plumes of smoke and ash enveloped everything in darkness, turning day into night. People living in villages near the mountain were caught unaware and some buried alive.
This description may sound like something you would read in your history textbook about Pompeii, a city that was buried by Mount Vesuvius in Italy in 79 AD. However, these were scenes from Guatemala last Sunday when Fuego, an active volcano erupted.
Aptly known as the Volcano of Fire (Volcán de Fuego), it has erupted several times in the last forty years. But this time, it was different. Fast-moving lava, along with smoke and ash quickly spread across five miles, burning everything in its path. President Jimmy Morales of Guatemala has declared a state of emergency in the affected areas. Flights were canceled as clouds of ash can cause airplane engines to fail.
A Conical Volcano
Did you know that Guatemala is on the infamous Ring of Fire, a chain of volcanoes and earthquake-prone areas around the Pacific Ocean? But what makes Fuego so much deadlier than Hawaii's Mt. Kilauea? It all has to do with the shape of the volcano.
Stratovolcanoes typically look like what most people imagine volcanoes to be – they have steep slopes leading up to a symmetrical cone and a small crater at the top with a vent. Stratovolcanoes contain layers of lava and other types of rocks. The lava is thick and highly viscous, causing eruptions to be explosive. The viscosity of the lava also gives stratovolcanoes their steep cone shape, because the lava cools before it can travel too far down the slope.
Some famous stratovolcanoes are Mt. St. Helens and Mt. Rainier in North America, Mt. Fuji in Japan, Pinatubo in the Philippines, Merapi in Indonesia and Cotopaxi in Ecuador, South America.
What Are Pyroclastic Flows?
Stratovolcanoes are particularly dangerous because of pyroclastic flows and lahars caused by their eruptions. A pyroclastic flow is a fast-moving super-hot current of gases, ash and volcanic debris that will wipe out everything in its path, like an avalanche.
While a pyroclastic flow may look like a cloud of ash, it moves at 50 miles an hour, and can have a temperature of 400-1300 degrees Fahrenheit. The hot rocks and gases can burn trees and houses in seconds. Lahars behave like an avalanche too, but they appear like wet concrete and are formed when the flowing ash and volcanic debris mixes with water.
Researchers believe it is hard to predict Fuego's fury because the volcano is constantly active, with several large explosions during the year and smaller ones during the day. They can not tell when the volcano has gotten into a heightened state of activity. One thing is for certain - the slopes of Fuego are not safe places to make a home as villagers are realizing.
Sources: Oregon State, BBC, NPR, Al Jazeera