Volcanoes eruptions that could change the world

Recent new of an increased activity of the Santorini Caldera is certainly bad news for crisis-stricken Greece although an eruption of Santorini as tragic as it would be for Greece and the Mediterranean is not the worst event to worry insurance companies and governments.

Below a list of the 6 nightmare volcanoes that could literally trigger catastrophe on a global scale in a relatively short timeframe.




1. KATLA (Iceland)
Last erupted: 1918
Effects of a major eruption: If Katla goes off, its eruption will be 10 times stronger than Eyjafjallajokull's. Katla's larger ash plume would shoot higher in the air and spread over larger areas of Europe for a longer period, with much more devastating effects on air travel and economic trade. An eruption could tip Europe's economy — perhaps even the world's — back into severe recession or a depression.
Likelihood: Fairly high. The two volcanoes, only 12 miles apart, tend to erupt in tandem, and Katla is slightly overdue in its 80-year cycle.
2. CUMBRE VIEJA (La Palma, Canary Islands)
Last erupted: 1971
Effects of a major eruption: In 2001, U.S. and British scientists warned that a major eruption of Cumbre Vieja could cause the enire western flank of the volcano to fall into the sea, creating a "mega-tsunami" in the Atlantic. Traveling at 500 miles per hour, it would wipe out Florida, coastal Brazil, and parts of Europe with waves up to 160-feet high. 
Likelihood: The scientists say the "year to year probability" of a major eruption is low, but preparations should be taken anyway given the potentially cataclysmic damages.
3. MT. VESUVIUS (Italy)
Last erupted: 1944
Effects of major eruption: Famous for wiping out Pompeii and Herculaneum in 79 A.D., Vesuvius would do much greater damage today. About 3 million people live near the volcano, 600,000 of them in the "red zone." An eruption would kill at least 8,000 people and cause more than $24 billion worth of damage, according to Willis Research Network, which just named Vesuvius the most dangerous volcano in Europe. The ash would change weather patterns in Europe and leave the Naples area a "lifeless desert."
Likelihood: Scientists say Vesuvius is overdue for an explosion.
4. POPOCATÉPETL (Mexico)
Last erupted: 2000
Effects of a major eruption: The third-tallest active volcano in the Northern Hemisphere, Popocatépetl is only 40 miles west of Mexico City and its 18 million inhabitants, and 30 miles east of Puebla, a city of two million. A large eruption could send deadly mudslides into the populous valleys below, creating "catastrophic" loss of life.
Likelihood: After an 80-year dormant period, Popocatépetl is showing signs of activity.
5. MT. TAMBORA (Sumbawa, Indonesia)
Last erupted: 1967
Effects of a major eruption: Tambora erupted in spectacular fashion in 1815 and changed weather patterns around the globe, causing "frosts in Italy in June and snows in Virginia in July, and the failure of crops in immense swaths across Europe and the America." The blow-up killed more than 71,000 people directly, and many more through famine and sickness.
Likelihood: Tambora is still active and, given its history and Indonesia's 222 million inhabitants, closely monitored.
6. YELLOWSTONE "SUPERVOLCANO" (U.S.)
Last erupted: 640,000 years ago
Effects of a major eruption: When the Yellowstone Caldera, or "supervolcano," in Yellowstone National erupts again, it will render a huge swath of North America, from Vancouver to Oklahoma City, uninhabitable. It would have incalculable human and economic consequences. The last eruption of similar magnitude — 73,000 years ago in Sumatra — plunged the entire planet into a decade-long volcanic winter and nearly wiped out the human race.
Likelihood: Geologists see signs that it could be preparing for another major blowout soon, although "soon" could mean thousands of years.

Santorini Caldera at risk of eruption

Should the Santorini Caldera erupt as per report below Greece economic woes would reach a totally new dimension:

From GAtech:

Newman, a geophysicist in the School of Earth and Atmospheric Sciences, cannot be certain whether an eruption is imminent since observations of such activity on these types of volcanoes are limited. In fact, similar calderas around the globe have shown comparable activity without erupting. However, Newman says the chamber has expanded by 14 million cubic meters since last January. That means enough magma has been pumped into the chamber to fill a sphere three football fields across.

Should Santorini erupt, Newman says it will likely be comparable to what the island has seen in the last 450 years.

“That could be dangerous,” notes Newman. “If the caldera erupts underwater, it could cause local tsunamis and affect boat traffic, including cruise ships, in the caldera. Earthquakes could damage homes and produce landslides along the cliffs.”

More than 50,000 tourists a day flock to Santorini in the summer months (from May to October). It’s common to see as many as five cruise ships floating above the volcano.

Santorini is the site of one of the largest volcanic events in human history. The Minoan eruption, which occurred around 1650 B.C., buried the major port city of Akrotiri with more than 20 meters of ash and created Santorini’s famous, present-day cliffs. Newman says such history will likely not repeat itself any time soon. Such an eruption comes along once every 100,000 years, and the current inflation in the magma chamber is less than 1 percent of the Minoan blast.