If I were in the U.S., I'd be more worried about the San Andreas fault and the "big one" due on San Francisco any time soon:

http://en.wikipedia.org/wiki/San_Andreas_Fault#The_Universit...

"The 2008 Uniform California Earthquake Rupture Forecast (UCERF) has estimated that the probability of an M ≥ 6.7 earthquake within the next 30 years on the northern and southern segments of the San Andreas fault as 21% and 59%, respectively."

A M 7 earhquake in California is bearly newsworthy and far from a significant threat. A low to mid 8 would cause significant property dammamge but few deaths. Even a 9 would only cause local problems. The Yellowstone Calder on the other hand would easily kill 50+% of everyone in the US with a low end eruption. Or put another way it's a significant threat to people livening in India.

PS: A great way of comparing threats is to multiply risk times death totals over a decade. On that scale terrorists and eathquakes are a joke.

In 1989 a 7.1 earthquake cause over $5bn of damage (excluding damage to roads, bridges, and State buildings.)

(http://www.cdc.gov/mmwr/preview/mmwrhtml/00001498.htm)

Wikipedia doesn't show many > 7 earthquakes. (https://en.wikipedia.org/wiki/Earthquakes_in_California#List...) (but maybe they have a weird inclusion criteria?)

Death's != property damage. Even the 10th most expensive hurricane to hit the US did 10billion in property damage with Katrina hitting 108 billion.

Consider the 9.0 that hit japan in 2011. Despite 129,225 buildings totally collapsed, with a further 254,204 buildings 'half collapsed', and another 691,766 buildings partially damaged it killed under 20,000 people.

That said, we have invested a lot to drive the death totals down in large part because earthquakes and hurricanes are fairly common. In comparison we are spending far to much on terrorism and far to little on the rare but civilization ending mega disasters.

> The Yellowstone Calder on the other hand would easily kill 50+% of everyone in the US with a low end eruption.

This stat is crazy. A low-end eruption (by far the most typical kind) at Yellowstone would kill few people in the U.S. The eruptions aren't that big and the Yellowstone downwind area is one of the least populated areas of the country.

Umm yea sorry, I meant high end eruption. I have no idea why I just said low.

The U.S. government dedicates many millions of dollars per year to monitoring Yellowstone, Rainier, the San Andreas Fault, and many other potential geologic threats.

Edit to add:

http://volcanoes.usgs.gov/observatories/yvo/index.html

What does this monitoring achieve, though, exactly? If the parent is correct in that a high end eruption at Yellowstone would kill >50% of the US's population, saying "hey guys, it's gonna erupt soon" doesn't do all that much for us.

Now, if our monitoring of earthquakes was advanced enough that we could say, "hey, San Andreas is gonna go nuts approximately 3 days from now in this general area", we could meaningfully evacuate people and save lives. But we don't have that kind of prediction accuracy.

Please cite your source.

Personally I'm more concerned by Mount Rainier, continental America's only "decade volcano".

"The Decade Volcanoes are 16 volcanoes identified by the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) as being worthy of particular study in light of their history of large, destructive eruptions and proximity to populated areas."

"More recently (since 2001) funding from the federal government for lahar protection in the area has dried up, leading local authorities in at-risk cities like Orting to fear a disaster similar to the Armero tragedy.[38][39]"