"Magma expanse under Yellowstone supervolcano more vast than thought"

the_syco

http://edition.cnn.com/2015/04/24/us/yellowstone-supervolcano-magma-reservoir-discovery/

1815, when Mount Tambora blew many cubic miles of debris skyward and killed about 10,000 inhabitants of Indonesia in an instant

Interesting stuff! Although we can shoot asteroids out of the sky, should this volcano erupt, we could be royally screwed, as when the (above) Tamora blew

Its dust may have blocked sunlight around the world, chilling the air and dropping the Earth's climate into a frigid phase that garnered the year 1816 the "year without a summer," some climatologists believe. It may have led to frosty crop failures in Europe and North America.

More importantly, we saw how air traffic was affected by the volcano in Iceland, so if Yellowstone blows, it could devastate not only the crops, but also worldwide air traffic as well!

Samaris

Tambora is on a far smaller scale than Yellowstone. We'd lose more than just air travel!

Yellowstone park is what's called a "supervolcano". It's a chain/cluster of volcanoes over a vast underground magma lake. At some point, the magma reservoir was emptied so quickly in a supereruption that the land above the now-empty chamber collapsed into it, forming the dish-like shape. The surface of the covering over the magma lake slowly expands from pressure, releasing gases in the form of mini-explosions.

If Yellowstone went off in a big way, and while it -will- at some point, it likely won't be for a fair bit of time yet, we'd probably lose most of the US and Canada to a thick blanket of dust. Imagine more Pompeii than Herculaneum. It's fairly near the northern pole, so the rotation of the earth would draw the massive cloud of dust northwards in general, although there would be enough of it to cover down to reasonably low latitudes. The rest of us would also suffer from it, although not as badly as we might otherwise. The magma in that region has a relatively low sulfur concentration, which is a major sun-blocker, so while our global temperature would drop a degree or two, it wouldn't be an iceball-causer. The upper levels of the US and Canada would likely be uninhabitable for a solid decade, maybe a bit less if enough rain falls to wash the ash away.