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New 'early warning sign' for volcanic eruptions

Volcanoes are primed to erupt on a time scale of days to months rather than years, research suggests.
The study raises hopes of finding a more accurate way to tell when a volcano is about to explode, scientists at Oxford University say.

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Rapid formation of bubbles in magma may trigger sudden volcanic eruptions

It has long been observed that some volcanoes erupt with little prior warning. Now, scientists have come up with an explanation behind these sudden eruptions that could change the way observers monitor active or dormant volcanoes.
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Polar ice cores reveal volcanic eruptions that changed human history

Researchers find new evidence that large eruptions were responsible for cold temperature extremes recorded since early Roman times
The study shows that 15 of the 16 coldest summers recorded between 500 BC and 1,000 AD followed large volcanic eruptions - with four of the coldest occurring shortly after the largest volcanic events found in record.

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Unrestricted access to the details of deadly eruptions

Details of around 2,000 major volcanic eruptions which occurred over the last 1.8 million years have been made available in a new open access database, complied by scientists at the University of Bristol with colleagues from the UK, US, Colombia and Japan.
The open access database of Large Magnitude Explosive Eruptions (LaMEVE) will provide this crucial information to researchers, civil authorities and the general public alike.

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Faraway volcanic eruptions now detected in a flash

A University of Washington-based network that monitors lightning around the globe has an unexpected new use: detecting volcanic eruptions that could be hazardous to aviation.
In its first months of test operations in Alaska and the Russian Far East, the system spotted two eruptions a full hour before they showed up on satellite images. That could mean valuable warning time for aircraft, whose engines can stall when clogged with volcanic ash.

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Predictions, Forecasting and Eruptions
In volcanology, a prediction would mean saying that a volcano will erupt with a specific type and magnitude of phenomena, at a very specific time. Volcanologists do not make predictions.

A forecast, however, involves probabilities, much like a weather report.

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New evidence showing that very large earthquakes can trigger an increase in activity at nearby volcanoes has been uncovered by Oxford University scientists.
An analysis of records in southern Chile has shown that up to four times as many volcanic eruptions occur during the year following very large earthquakes than in other years.
This volcanic surge can affect volcanoes up to at least 500 km away from an earthquakes epicentre. A report of the work will be published in the journal Earth and Planetary Science Letters.
Previously, scientists had identified a few cases where volcanic eruptions follow very large earthquakes but up until now it had been difficult to show statistically that such earthquakes may be the cause of an increase in eruptions, rather than the events just being a coincidence.

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Violent volcanic eruptions witnessed from the dawn of time to the present day could all have been prompted by meteorite strikes billions of years ago.
Geologists are presenting new evidence that contradicts the belief the gas that causes volcanoes to erupt 'light' helium came to Earth via its gravitational pull.
Volcanic eruptions occur when the gas, which arrived when the world was in a molten state and is trapped in the deep Earth, melts.
But University of Manchester scientists say that the 'fingerprint' left by the 3He isotope does not match solar nebula but instead meteorites.

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A volcano on the largest of the Galapagos Islands has begun erupting, park officials said Friday. Rangers and tour guides spotted lava flowing down the northeastern flank of the Cerro Azul volcano on the seahorse-shaped island of Isabela late Thursday, the Galapagos National Park said in a statement.

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On the westernmost island in the Galapagos Islands lies the volcanic chain’s most active volcano: Fernandina. Located on a remote, uninhabited island in the Galapagos National Park, the volcano’s eruptions often go unobserved, but on May 13, 2005, the volcano’s eruption was unmistakable.
A short time after the volcano started to erupt, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) flying on the OrbView-2 satellite captured this image.



A thick cloud of ash and steam rises from the volcano and fans out to the west. A smaller, slightly darker plume is blowing south from the island. This darker plume may be more ash-rich than the larger plume, or it may be smoke from fires ignited by lava flows.

The Instituto Geofisico of the Escuela Politecnica Nacional of Ecuador reports that ash rose to a height of seven kilometers from a fissure on the west side of the volcano. Volcanic material has fallen on the neighboring Isabela Island.
The volcano’s last eruption was in 1995.

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