Satellite detection of hazardous volcanic clouds and ... - Savaa - NILU

Nat HazardsFig. 8 Asia Pacific regional air traffic density from monthly averaged forecast NOx emissions for FL 350 toFL 390 (pressure altitudes of 33,000 ft up to 39,000 ft) taken from the AERO2k emissions inventory ofEyres et al. (2004). Forecast emissions are shown for April 2025. The colour code is linearly scaled withgreatest emissions represented as deepest blue. The red triangles indicate the positions of Holocene andHistorically listed volcanoes taken from the Smithsonian database (Simkin and Siebert 1994). There are over450 volcanoes indicated on the plot. The AIRS SO 2 column observations from the eruption of Anatahanduring 6–8 April 2005 are also shown on this plot. These data are scaled to show the relative columnamounts each day as observed by AIRS, with red representing the highest values and lilac, the lowestThis much more objective estimate of the cloud height can then be used to forecast thecloud movement with greater confidence and accuracy. For some regions, where 15-mininfrared data are available from geosynchronous satellites, it will be possible to reliablytransmit accurate 3D trajectories of hazardous volcanic clouds for use by the aviationindustry. By supplying height and horizontal spatial information on the location andmovement of volcanic clouds, the aviation industry will be able to re-route air traffic asnecessary and at the same time minimize the extra fuel used. Satellite data can also be usedto identify volcanic clouds that are predominantly composed of SO 2 and/or volcanic ash.This information may be used by the aviation industry to determine the appropriate postmaintenanceprocedures required in the event of an encounter with a volcanic cloud. Asash is known to cause engine damage and clogging of pitot static tubes and SO 2 is notimplicated in this kind of damage, there may be an economic advantage in utilizing thisinformation.It has been noted that commercial and freight air traffic is growing globally andregionally, with the Asia Pacific region experiencing one of the highest annual growthrates. The region also contains many volcanoes and is thus vulnerable to air traffic volcanic123