Abstract
Abstract. The Multi-angle Imaging SpectroRadiometer (MISR) Research Aerosol algorithm makes it possible to study individual aerosol plumes in considerable detail. From the MISR data for two optically thick, near-source plumes of the spring 2010 Eyjafjallajökull volcano eruption, we map aerosol optical depth (AOD) gradients and changing aerosol particle types with this algorithm; several days downwind, we identify the occurrence of volcanic ash particles and retrieve AOD, demonstrating the extent and the limits of ash detection and mapping capability with the multi-angle, multi-spectral imaging data. Retrieved volcanic plume AOD and particle microphysical properties are distinct from background values near-source, as well as for over-water cases several days downwind. The results also provide some indication that as they evolve, plume particles brighten, and average particle size decreases. Such detailed mapping offers context for suborbital plume observations having much more limited sampling. The MISR Standard aerosol product identified similar trends in plume properties as the Research algorithm, though with much smaller differences compared to background, and it does not resolve plume structure. Better optical analogs of non-spherical volcanic ash, and coincident suborbital data to validate the satellite retrieval results, are the factors most important for further advancing the remote sensing of volcanic ash plumes from space.
Highlights
Satellite observations can play a key role in constraining aerosol transport models used to diagnose the environmental impacts of volcanic eruptions (e.g., Stohl et al, 2011; Heinold et al, 2012)
This paper explores the ability to retrieve and to map, with data from the NASA Earth Observing System’s Multiangle Imaging SpectroRadiometer (MISR) instrument, particle properties for both near-source and downwind volcanic plumes
Whereas the near-source analysis allows us to look at variability and changing particle properties within the plume, the downwind case analyses focus on the limits of MISR ability to detect and map volcanic plumes
Summary
Satellite observations can play a key role in constraining aerosol transport models used to diagnose the environmental impacts of volcanic eruptions (e.g., Stohl et al, 2011; Heinold et al, 2012). For eruptions of Mt. Etna between 2000 and 2008, Scollo et al (2012) demonstrated that the MISR V22 Standard aerosol product was able to detect even low concentrations of volcanic ash in the atmosphere, and on about ten occasions for which there were ground-based validation data, MISR reliably distinguished sulfate- and/or water-dominated from ash-dominated plumes. Etna between 2000 and 2008, Scollo et al (2012) demonstrated that the MISR V22 Standard aerosol product was able to detect even low concentrations of volcanic ash in the atmosphere, and on about ten occasions for which there were ground-based validation data, MISR reliably distinguished sulfate- and/or water-dominated from ash-dominated plumes This distinction is indicative of eruption strength, and is otherwise unmonitored for most volcanoes around the world.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
