The No-Fly zone criticized by scientists

After ash from the eruption in Grimsvotn halted all air traffic through Icelandic airports last Sunday some people have demanded that the risk assessment be changed. As of now the Icelandic civil aviation authorities, Isavia, use the ash dispersion forecasts from the Volcanic Advisory Centre (VAAC), made by the British Met Office.

Dr. Jonas Eliasson, Professor Emeritus at the Earthquake Engineering Research Centre of the University of Iceland, says in an interview with the Frettabladid newspaper that the no-fly zone is much too big. Instead of closing airports on the basis of information from foreign institutes the right equipment should be put up in Iceland.

"We made our own measurements at Keflavik airport yesterday [Sunday], while the closure was still in force, and found out that the ash concentration was 11 micrograms per cubic metre, which is far below the danger threshold, and the concentration in Reykjavik last night, when the cloud went over, was 350 micrograms." The allowed limit for instrument flying is now 2,000 micrograms per cubic metre.

Eliasson says that Icelandic institutes should acquire equipment and personnel to be able to make independent decisions.

"The Icelandic civil aviation authorities must be more proactive in these matters. We are the only country in this region that has volcanoes. Therefore, the measurements should be made here." Eliasson says that with more precise measurements the danger zones can be better defined.

Asgeir Palsson, director of Isavia, says there is nothing wrong with receiving advice from VAAC in London, because their forecasts are partly based on data collected by official Icelandic institutes. "We can estimate certain, local conditions, but we cannot ignore the forecast charts altogether," says Palsson.

"The numbers from the measurements yesterday, 350 micrograms, only tell us what the concentration was in that specific place. In other areas there can be pockets where the ash is much more concentrated."

Palsson adds that although a measurement of 350 micrograms is under the limit, it is still a quantity that can shorten the service life of jet engines.

"So, although we would allow flights in such conditions, I don't think the airlines would want to fly."

The spokesmen for the two Icelandic airlines, Icelandair and Iceland Express, say they are satisfied with how things were handled this time, and that they completely understand how the system works, although it would be good to have more accurate measurements to eliminate all uncertainty.