Transportation and deposition of volcanic ash from Iceland to the Arctic

Sammanfattning: As the Arctic will become more available to shipping traffic in the future, given the current trend of diminishing ice sheets continues, the emission of particles and gases originating from ships will increase in the Arctic. The emission of particles and gases can affect the sensitive Arctic environment in many ways, e.g. change albedo by deposition, affect air traffic, harm livestock and humans etc. Therefore it is of interest to explore the seasonal effect on the atmospheric circulation and dispersion of particles to the Arctic. The concentration and deposition of volcanic ash particles with regard to air traffic is also explored. The dispersion and deposition is explored by studying dispersion and deposition of volcanic ash in the programme “Danish Emergency Response Model of the Atmosphere” (DERMA) in operation at the Danish Meteorological Institute (DMI). The result shows a winter season that is characterized by dispersion and deposition of particles into the Arctic, while the summer season has little or no dispersion or deposition into the Arctic. In summer, Europe receives the largest deposition of particles (1 g/m2) while the Arctic receives the largest amount of ash particles in the winter (> 1 g/m2). The deposition of ash particles in the Arctic creates a very thin layer of ash particles that most likely does not affect the albedo of the ice and snow-covered surface. Therefore the short- and long-term climate effects are not significant. The effect of ash particles on air traffic is minor and the area affected shifts depending on the season due to the difference in dispersion. The major impact on air traffic is most likely delays of some departures. However, it is important to keep in mind that to fully prove a seasonal difference in dispersion and deposition, a more detailed and precise investigation needs to be carried out with statistics of the different seasons.