Atmospheric Measurement Techniques Observation of volcanic ash from Puyehue–Cordón Caulle with IASI

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 In-frared 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 Hemi-sphere. 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 vol-canic ash. Since IASI observations in the 8–12 µm window are ap-plied in the retrieval, the method is insensitive to solar illu-mination and therefore yields twice the observation rate of the ash plume evolution compared to solar backscatter meth-ods 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.