On Sunday, November 3, 2002, Mt. Etna's ash-laden plume was imaged by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. The plume is seen blowing toward the south-southeast, over the city and airport of Catania, Sicily. The previous day, the plume was blowing toward the northwest, and posed no hazard to Catania. The current eruption of Mt. Etna, Europe's most active volcano, began on October 27. These sorts of observations from space may help civil defense authorities mitigate hazards from active eruptions. Space data may also help scientists evaluate the behavior and effects volcanic eruptions have on our global climate system.
http://photojournal.jpl.nasa.gov/catalog/PIA03881