Observation of volcanic ash from Puyehue–Cordón Caulle with IASI

Abstract. On 4 June 2011 an eruption of the Chilean volcano complex Puyehue–Cordón Caulle injected large amounts of volcanic ash into the atmosphere and affected local life as well as hemisphere-wide air traffic. Observations of the Infrared Atmospheric Sounding Interferometer (IASI) flown on board of the MetOp satellite have been exploited to analyze the evolution of the ash plume around the Southern Hemisphere. A novel singular vector-based retrieval methodology, originally developed for observation of desert dust over land and ocean, has been adapted to enable remote sensing of volcanic ash.

Since IASI observations in the 8–12 μm window are applied in the retrieval, the method is insensitive to solar illumination and therefore yields twice the observation rate of the ash plume evolution compared to solar backscatter methods from polar orbiting satellites. The retrieval scheme, the emission characteristics and the circumpolar transport of the ash are examined by means of a source–receptor analysis.