Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions,[1] less than 2 millimetres (0.079 in) in diameter. 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.
The second eruption of Eyjafjallajökull volcano in Iceland on 14 April 2010 is causing extensive air travel disruption across large parts of Europe.[1] In response to fears that particles ejected by the volcano into standard flight corridors could damage aircraft engines,[2] the controlled airspace of many countries was closed to IFR traffic, stranding millions of travellers. It is the largest air traffic shut-down since World War II.[3]
The eruption occurred beneath glacial ice, with the cold water from melting ice chilling the lava quickly, causing it to fragment into very small particles of glass (silica) and ash which were carried into the eruption plume. Due to the extremely fine nature of the ash particles and the large volume of steam produced from the glacial melt water, the ash plume hazardous to aircraft was rapidly sent high into the upper atmosphere. [4] The presence and location of the plume depended upon the state of the eruption and the winds. Due to the way air-masses function and the large volume of steam produced by this eruption, the plume was injected into the jet stream.[5]
With large parts of European airspace closed to air traffic,[6][7][8] many more countries were affected as flights to and from Europe were cancelled.
As of 17 April 2010, 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.[9] The forecast for 18 April at 06:00 showed a significant plume continuing over northern Europe.[10] 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.[11]
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.[12]
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