Volcano Ash Cloud approaching from Iceland - Air travel disruption after the 2010 Eyjafjallajökull eruption

Description:

Meteosat-9 observes the ash cloud from the volcanic eruption under Eyjafjallajoekull Glacier in Iceland. Over the course of the day it has moved steadily east and has nearly reached Sweden.

 

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Second eruption of Eyjafjallajökull

The second eruption of Eyjafjallajökull volcano in Iceland on 14 April 2010 is causing extensive air travel disruption across large parts of Europe. In response to fears that particles ejected by the volcano into standard flight corridors could damage aircraft engines, the airspace of many countries was closed, stranding millions of travellers. It is the largest air traffic shut-down since World War II.

The eruption occurred beneath glacial ice, and the cold water from melting ice chilled the lava quickly, causing it to fragment into glass, creating small glass particles that were carried into the eruption plume. This, together with the magnitude of the eruption, sent a glass-rich plume hazardous to aircraft into the upper atmosphere. The presence and location of the plume depended upon the state of the eruption and the winds. Due to the way air-masses function, the plumes tended to be injected into the jet stream.

With large parts of European airspace closed to air traffic, many more countries were affected as flights to and from Europe were cancelled.

As of 17 April 2010 (2010 -04-17)[update], the eruption was continuing, but less explosively; the plume was rising to 5 kilometres (3 mi) rather than 13 kilometres (8 mi) previously; not high enough to travel across Europe. The forecast for 18 April at 06:00 showed a significant plume continuing over northern Europe. At 20:00 UTC on 16 April the ash cloud reached Kazakhstan. Jet stream forecasts indicated the ash cloud plume would persist until at least 21 April, shifting to the south and affecting more southerly parts of France and Italy.

The International Air Transport Association (IATA) estimated that the airline industry worldwide would lose €148 million (US$200 million, GB£130 million) a day during the disruption.

Volcanic Ash

Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than 2 millimetres (0.079 in) in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact with water causing phreatomagmatic eruptions, and ejection of entrained particles during steam eruptions causing phreatic eruptions. The violent nature of volcanic eruptions involving steam results in the magma and solid rock surrounding the vent being torn into particles of clay to sand size. Volcanic ash can lead to breathing problems, malfunctions in machinery, and from more severe eruptions, years of global cooling.

Ash deposited on the ground after an eruption is known as ashfall deposit. Significant accumulations of ashfall can lead to the immediate destruction of most of the local ecosystem, as well the collapse of roofs on man-made structures. Over time, ashfall can lead to the creation of fertile soils. Ashfall can also become cemented together to form a solid rock called tuff. Over geologic time, the ejection of large quantities of ash can produce an ash cone.

(Text: Wikipedia)