I d be very interested to learn how he draws the line of 'super' There are definitely volcanos that are much bigger than most volcanos, but I don't think any of them are in Italy or the US. Anyone know which he considers 'super' volcanos in these places? That said, a 'super' volcano can have major global climatic effect. The New England colonies once had the 'year without summer' (snow in July and Aug) due to an eruption in the Pacific.
DannyTN just showed you one in the USA.
Yellowstone is a supervolcano. Seriously, what is all the steam and sulfur and frequent earthquakes all about? And that is when it is quiescent.
The biggest badest volcano of them all is right here in the good old USA,Yellowstone, and it goes off large about every 600,000 years. And the last large eruption was, you guessed it, 600,000 years ago.
Check out the history of the hot spot that is now under Yellowstone NP before you conclude that the US has no risk.
yellowstone is one huge volcano (caldera) its surface has rose 2-3 feet in the recent past. when it goes
so do the cockroaches. :D
Yellowstone National Park is one such Super Volcano.
Volcanologists use two measures of eruption size: the magnitude of the eruption (the volume or mass of magma erupted)and the intensity (the rate of magma eruption). (Magma is the hot, molten, often gas-laden rock material stored under volcanoes.) In principle, these two parameters are independent, but there is good evidence that they are linked. Thus, super-eruptions are not only huge (high magnitude), but also very violent (high intensity).
To give some comparison, Mount St. Helens in 1980 erupted less than one cubic kilometre of magma. Vesuvius (AD 79) erupted about five cubic kilometres, and Krakatoa* (1883) about 12 cubic kilometres. The biggest eruption of the past few hundred, perhaps one thousand, years, that of Tambora volcano (Indonesia, 1815) released about 30 cubic kilometres of magma.
The biggest super-eruption recognised so far produced approximately 5000 cubic kilometres, creating the so-called “Fish Canyon Tuff event” in Colorado, USA.
Campi Phlegreia caldera volcano that produced a super-eruption about 35,000 years ago is across the bay from Naples from Vesuvius.