Multi-angle Imaging SpectroRadiometer (MISR) Volcano Research Project

These datasets contain output from comprehensive analyses of volcanic plumes in the Multi-angle Imaging SpectroRadiometer (MISR) data record. MISR offers two unique capabilities that can contribute to understanding aerosol plumes. From MISR hyper-stereo observations, plume height and the associated wind vectors are derived geometrically using the MISR INteractive eXplorer (MINX) software (Nelson et al., 2013). The results include maps of plume elevation, and also give some indication of plume vertical extent from the range of height values among the 1.1 km pixels. The retrieved elevations are corrected for the proper motion of plume elements based on retrieved wind vectors. Vertical resolution is between 250 m and 500 m. MISR plume-height retrievals are obtained primarily near major aerosol sources such as wildfires and erupting volcanoes, as plumes must be sufficiently optically thick so aerosol features are visible in the multi-angle imagery. In addition, qualitative constraints on particle microphysical properties – size, shape, and light-absorption, are retrieved radiometrically, using the MISR Research Aerosol (RA) retrieval algorithm (Kahn and Gaitley, 2015; Limbacher and Kahn, 2019). About 3-5 bins in particle size (e.g., “small,” “medium,” and “large”), 2-4 bins in single-scattering albedo (SSA), “flat” or “steep” light-absorption spectral slope, and spherical vs. randomly oriented non-spherical particles can be distinguished under good but not necessarily ideal retrieval conditions. To obtain high-quality particle property retrievals, mid-visible aerosol optical depth (AOD) of at least ~0.15 or 0.2 is generally required. As such, major aerosol plumes are among the best targets for MISR particle property retrieval. Often, the evolution of particles can be inferred from downwind changes in plume-particle properties, and the mechanisms involved, such as size-selective or size-independent gravitational settling, particle hydration, and secondary particle formation, can be inferred.
Disciplines:   Aerosols
Collection Disciplines Spatial Temporal
MISR Derived Case Study Data for Iceland Volcanic Eruptions (Eyjafjallajokull, Grimsvotn, Holuhraun) Including Geometric Plume Height and Qualitative Radiometric Particle Property Information
Aerosols Spatial Coverage:
(50, 70), (-30, 5)
Horizontal Resolution Range:
1 km - < 10 km or approximately .01 degree - < .09 degree
Vertical Resolution Range:
100 meters - < 1 km
Vertical Resolution:
250  m
Temporal Coverage:
2010-04-15 - 2015-02-21
Temporal Resolution Range:
Daily - < Weekly