Are we ready for the next volcanic catastrophe?

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Guardian said:
The largest eruption ever recorded, in Indonesia 200 years ago, wreaked havoc across the world, causing hunger, disease and death for years afterwards. When a volcanic event on that scale happens again – and it will – we should be prepared for serious disruption to our climate and food production. http://www.theguardian.com/world/20...xt-big-volcanic-eruption-tambora-bill-mcguire

Vilfredo Pareto, Italian polymath of the turn of the previous century, and his power law probability distribution of geophysical phenomena (see Pareto Distribution) continues to inform and protect.
 
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Iceland is a most complicated volcanic site, with both a plume and a hotspot origin hypothesized. It is on a 100 meter bulge from the reference Earth geoid. It is among the most active sites with 39 eruptions in the Twentieth Century. Not of the 'caldera' type of Long Valley or Yellowstone in North America.

Tuesday I start my 1500 mile drive home and I'm far more worried about that than volcanism or earthquakes in my lifetime.
 
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Greg Bernhardt said:
Anyone have a map of volcanic hot spots? Is Iceland a worry?

Now assuming you meant "volcanic hotspot" as in the true meaning and not just locations of active volcanoes ? ...
OK here's a Hotspot image ( best I could find after going through dozens of images haha)

from
http://geology.about.com/od/platetectonicmaps/ss/World-Hotspots-Map.htm

hotspotmap.jpg
This map shows the hotspots listed in an influential 2003 paper by Vincent Courtillot and colleagues, which ranked them according to a set of five widely accepted criteria. The three sizes of symbols show whether the hotspots had high, medium or low scores against those criteria. Courtillot proposed that the three ranks correspond to an origin at the base of the mantle, the base of the transition zone at 660 kilometres depth, and the base of the lithosphere. There is no consensus on whether that view is valid, but this map is handy for showing the names and locations of the most commonly mentioned hotspots.
Some hotspots have obvious names, like Hawaii, Iceland and Yellowstone, but most are named for obscure ocean islands (Bouvet, Balleny, Ascension), or seafloor features that in turn got their names from famous research ships (Meteor, Vema, Discovery). This map should help you keep up during a talk aimed at specialists

here's another ...
Don_Anderson_GlobalHotspotMaps-4_Fig_2.jpg


many images didn't even show Iceland as a hotspot

Greg Bernhardt said:
... Is Iceland a worry?

I would suspect not, with Iceland being a very active spreading ridge, the hotspot doesn't get time to build up significant pressure
to produce the massive volcanic explosions that we would associate with say the Yellowstone Caldera.cheers
Dave
 
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An interesting report on an Ice Age super volcano associated with climate variability and significant magnetic field disturbance.

http://www.sciencedaily.com/releases/2012/10/121016084936.htm
121016084936-large.jpg


Some 41,000 years ago, a complete and rapid reversal of the geomagnetic field occurred. Magnetic studies on sediment cores from the Black Sea show that during this period, during the last ice age, a compass at the Black Sea would have pointed to the south instead of north. Moreover, data obtained by the research team, together with additional data from other studies in the North Atlantic, the South Pacific and Hawaii, prove that this polarity reversal was a global event.

Abrupt climate changes and a super volcano

Besides giving evidence for a geomagnetic field reversal 41,000 years ago, the geoscientists from Potsdam discovered numerous abrupt climate changes during the last ice age in the analysed cores from the Black Sea, as it was already known from the Greenland ice cores. This ultimately allowed a high precision synchronisation of the two data records from the Black Sea and Greenland.

The largest volcanic eruption on the Northern hemisphere in the past 100,000 years, namely the eruption of the super volcano 39,400 years ago in the area of today's Phlegraean Fields near Naples, Italy, is also documented within the studied sediments from the Black Sea. The ashes of this eruption, during which about 350 cubic kilometers of rock and lava were ejected, were distributed over the entire eastern Mediterranean and up to central Russia.

These three extreme scenarios, a short and fast reversal of Earth's magnetic field, short-term climate variability of the last ice age and the volcanic eruption in Italy, have been investigated for the first time in a single geological archive and placed in precise chronological order