This animation shows cloud movement using data from the Meteosat Second Generation (MSG) satellite.
The main volcanic ash cloud can be identified as the bright orange plume that’s being carried eastwards from southern Iceland.
Different colours have been used to represent different types of cloud and do not correspond to the actual colours that would be seen by the human eye.
These early images are not showing a great deal of information on the ash plume (orange) itself because of the presence of overlying high cloud (coloured black and darker red).
From around 0600 GMT on 15 April the ash plume starts appearing from southern Iceland, just to the south of an area of high cloud. Over the following few hours the main ash plume continues to travel eastwards towards the Norwegian coast, and then begins to move southwards, reaching Shetland soon after 1000 GMT. By 2000 GMT, the easterly edge of the main ash plume has reached the northern tip of Denmark, with other parts of the ash skirting north-eastern Scotland and moving southwards over the North Sea.
MetOffice
Which pollutants can be found in the plume?
Nobody knows the exact composition of the Icelandic volcano plume, but the pollutants of greatest concern to human health in plumes from volcanoes are normally mineral particulates, sulphur dioxide (SO2), fluoridic acids and hydrochloric acid.
NERI will also follow the development through its regular air quality monitoring network. The results can be followed on-line at our website.
If parts of the plume reach ground level, it will most likely be registered at first in Aalborg and then i Copenhagen and most likely as an increase in the concentration of SO2. Until Friday afternoon 4 p.m. no increases had been observed. This may be explained by information from Iceland that the first plumes were emitted to 10-12 km. NERI will run a new prognosis during the weekend.
DMU.DK
Icelandic Volcanoes Can Be Unpredictable and Dangerous
ScienceDaily (Apr. 16, 2010) — If history is any indication, the erupting volcano in Iceland and its immense ash plume could intensify, says a Texas A&M University researcher who has explored Icelandic volcanoes for the past 25 years.
Jay Miller, a research scientist in the Integrated Ocean Drilling Program who has made numerous trips to the region and studied there under a Fulbright grant, says the ash produced from Icelandic volcanoes can be a real killer, which is why hundreds of flights from Europe have been canceled for fear of engine trouble.
“What happens is that the magma from the volcano is around 1,200 degrees and it hits the water there, which is near freezing,” he explains. “What is produced is a fine ash that actually has small pieces of glass in it, and it can very easily clog up a jet engine. If you were to inhale that ash, it would literally tear up your lungs.”
Miller says most volcanoes in Iceland erupt only about every five years on average and are relatively mild, but history is repeating itself. Extremely large eruptions occurred there in 934 A.D. and again in 1783 that covered Europe with ash much like today.
“Ben Franklin was ambassador to France in 1783 and he personally witnessed the large ash clouds over Europe, and he later wrote that it was a year in which there was no summer,” Miller adds. “The big question now is, what happens next? It’s very possible this eruption could last for quite some time, but no one knows for sure. Volcanoes in that part of the world are very hard to predict.”
Story Source: Adapted from materials provided by Texas A&M University
Iceland Volcano Could Continue Erupting for More Than a Month, Researcher Says
ScienceDaily (Apr. 16, 2010) — The airspace over much of northern Europe remains shut and the Norwegian Prime Minister, Jens Stoltenberg, is stranded in New York City because of the threat from a volcanic ash plume being belched out of Iceland. How long will the eruption of the Eyjafjallajokull volcano continue and what other kinds of activity can we expect? A volcanologist at the Norwegian University of Science and Technology (NTNU) who has worked extensively in Iceland says a month-long eruption would not be out of the question. But the eruption could also continue for a year or more, he says.
Professor Reidar Trønnes, who was a research scientist at the University of Iceland’s Nordic Volcanological Institute from 2000 to 2004, says as eruptions go, the Eyjafjallajokull volcano is not that large. Nevertheless, concerns about the effects of volcanic ash on jet engines led to a range of airport closures in northern Europe on Friday.
Volcanic ash, which is made up of tiny glass shards that are carried aloft in a foamy mix of steam, can damage jet engines by melting right inside them and causing them to seize up. “
Residents from a number of central Norwegian cities reported the smell of sulphur in the air, and some residents in northern Norway reported finding volcanic ash on their automobiles. Trønnes says that the ash gets shot high into the air as magma that was once deep in the Earth comes to the surface and is depressurized. Any water that has dissolved in the magma comes boiling out when the magma is no longer under pressure, much the way that CO2 bubbles out of your selzer water when the cap is removed, he says. The plume coming out of the Eyjafjallajokull volcano also contains a good deal of steam because the intensely hot magma is melting the ice cap that blankets the volcano, he adds.
While the Eyjafjallajokull volcano’s eruption is highly dramatic, most volcanologists like Trønnes are watching the volcano’s much larger neighbour to the east, Katla. This volcano, buried under the Mýrdalsjökull glacier, Iceland’s fourth largest ice sheet, usually erupts twice a century, Trønnes says, but has erupted just once in the last 100 years — in 1918. “Katla has had two large eruptions every century since Iceland was settled 1,100 years ago,” he said. “It is long overdue — or it could mean that Katla has changed its behaviour.”
Trønnes said that a number of large volcanic eruptions over the last several decades may have helped drain the vast magma reservoirs that would feed any eruption of Katla. These include eruptions as far back as one that created the island of Surtsey in 1963-1967 and one that took place on nearby Heimaey in 1973. “The fact that we have had these two large eruptions in the 1960s and 1970s may have relieved the pressure in the Katla reservoir, although this is just speculation,” he said.
The Eyjafjallajokull volcano now appears to have released enough pressure that Trønnes does not expect any large-scale explosions, but the melting of the glacier caused by lava flows will continue to pose risks of potentially large and devastating floods, such as one that caused Icelandic officials to evacuate 800 people from their homes on Wednesday, April 14, he said.
Story Source: Adapted from materials provided by The Norwegian University of Science and Technology (NTNU), via AlphaGalileo.
Via MadridMas
