Volcanic Explosivity Index

Volcanic Explosivity Index

This is a scale that explains the magnitude of an eruption.

VEI	Description	Plume Height	Volume	Classification	How often	Example
0	non-explosive	< 100 m	1000s m³	Hawaiian	daily	Kilauea
1	gentle	100-1000 m	10,000s m³	Haw/Strombolian	daily	Stromboli
2	explosive	1-5 km	1,000,000s m³	Strom/Vulcanian	weekly	Galeras, 1992
3	severe	3-15 km	10,000,000s m³	Vulcanian	yearly	Ruiz, 1985
4	cataclysmic	10-25 km	100,000,000s m³	Vulc/Plinian	10's of years	Galunggung, 1982
5	paroxysmal	> 25 km	1 km³	Plinian	100's of years	St. Helens, 1981
6	colossal	> 25 km	10s km³	Plin/Ultra-Plinian	100's of years	Krakatau, 1883
7	super-colossal	> 25 km	100s km³	Ultra-Plinian	1000's of years	Tambora, 1815
8	mega-colossal	> 25 km	1,000s km³	Ultra-Plinian	10,000's of years	Yellowstone, 2 Ma

Table from Russ Rowlett and the University of North Carolina at Chapel Hill

According to the chart, the eruption at Mount Katmai in 1912 is a six. Good thing they only come along every couple hundred years!!

Conclusion

Mount Katmai is a little known Volcano with a big past. The eruption of 1912 is worth knowing, and hey, it is good knowledge to impress your friends with! You can visit Mount Katmai and further impress them by telling them you were at the site of the biggest volcanic eruption of the 20th century.

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