In mid-April the Eyjafjallajökull volcano produced the eruption that affected aviation in areas throughout Europe. In order to measure the concentration of ash in the atmosphere, large numbers of air samples were collected. Sweden was the only Nordic representative, and one of the few countries in Europe, capable of carrying out this atmospheric sampling. Measurements taken in Swedish airspace involved cooperation between FOI, the Swedish Armed Forces, the Swedish Meteorological and Hydrological Institute (SMHI), the Swedish Transport Agency and the Swedish air navigation agency LFV. FOI scientists then analysed the results of the measurements.

“Our results are in line with corresponding results produced by research institutes in other countries including Germany, the United Kingdom and the Netherlands. Carrying out observations of the concentration of ash in the atmosphere is of crucial importance if we are to be able to verify the dispersion models used to underpin decisions regarding the closure of airspace to civil air traffic,” Tomas Mårtensson, a research meteorologist at FOI, tells us.

At the beginning of July representatives of aviation companies, airports, air traffic control agencies, the aircraft industry, aviation weather services, research institutes and other interested organisations, gathered for a workshop on the consequences of the ash cloud. Apart from discussion of how good the models are at predicting concentrations, much time was given to discussing what particle concentration levels should be considered damaging to aircraft engines.

“Regardless of the time aspect, there is a pressing need to improve the decision support models for how to deal with ash clouds. It is more than likely that the EU Commission will be receiving a good many applications for research projects in this field,” says Tomas Mårtensson.