What about what lies beneath? Earthquakes are terrifying forces of nature, and nowadays their power is measured by scientists on the moment magnitude (Mw) scale. It is not a linear scale – a M2 rating is equivalent to a tremor roughly 30 times as energetic as a M1 quake.
Earthquakes prior to human documentation are difficult to energetically quantify, so only recorded ones can be compared. Just in terms of total energy released, the most powerful recorded earthquake is thought to be the May 22, 1960 event that struck southern Chile. Measured as a M9.5, it would have unleashed 8.3 quintillion joules of energy in mere seconds.
So how does this compare to hurricanes? Well, say you have an average hurricane lasting for 24 hours. That means in a single day (86,400 seconds), it will unleash around 52 quintillion joules of energy. So the world’s most powerful earthquake doesn’t even come close to the most standard of hurricanes.
Volcanic eruptions produce fiery columns of ash and lava, huge lava flows, massive amounts of kinetic energy through ballistics and bombs, huge quantities of sound energy, and more. Make no mistake, they are powerful. Although effusive ones producing lava flows emit more energy overall, explosive eruptions – such as the famous May 1980 event at Mount St. Helens – produce more energy per second by far, and are considered the most conventionally “powerful”.
The most powerful eruption in the last 500 million years is thought to be the one that formed La Garita Caldera, an extinct supervolcano located in Colorado. This unleashed in a matter of hours or days 5,000 cubic kilometers (1,200 cubic miles) of lava and ash, via huge eruption columns and pyroclastic flows, enough to bury the entire state of California under 12 meters (40 feet) of volcanic debris.
As a point of comparison, the largest nuclear weapon ever detonated, the Tsar Bomba, released 0.2 quintillion joules of energy. This 28-million-year-old eruption involved over 1,050 quintillion joules of energy – 5,000 times more powerful than humanity’s feeble efforts. So far, this is the world’s most powerful natural disaster.
More and more volcanoes nowadays exist among densely populated settlements, and become more hazardous year on year as their nearby populations grow. Anton Jonkovoy/Shutterstock