Data Product Summaries|
Part II: Eruption Cloud Products
SCF = Science Computing Facility
Product Number --- Product Name (Key Responsible Team Member)
3263 --- Eruption Cloud Particle Maps
William I. Rose, e-mail: raman#mtu.edu (change # to @ to break SPAMblock)
Description: Maps of eruption clouds will be produced, showing optical depth, effective particle radius, or mass loading per km2 for each type of cloud particle. There will be separate maps for each aerosol type, depending on which types are present (silicate ash, H2SO4, ice, and/or water). The spatial resolution will be 1 km. The current algorithm can only be applied to semitransparent eruption clouds in the stratosphere, but we are attempting to modify it to work for lower-altitude clouds.
Input: MODIS Level 1B radiance data (MOD02), channels 27, 29, and 31 through 36.
Output from Mich. Tech. Univ. SCF (HDF File Format, No Browse Images Available): For approximately 2 to 8 eruptions per year, 8-bit raster image maps will be generated which show retrievals of cloud particle size (effective radius), optical depth, or mass loading. Ancillary information provided with these retrievals will include particle type, total mass loading (for each particle type and all particles combined), and the particular assumptions that went went into the retrieval (such as plume altitude, thickness, and ash composition). Total of 5 to 25 maps per year, 500 km x 500 km area per map, 1 km spatial resolution, 0.5 Mb/map.
Software to be made available: User-interactive software package written in IDL (Interactive Data Language) for creating eruption cloud particle maps from MODIS data.
References:Wen, S, and WI Rose (1994) Retrieval of sizes and total masses of particles in volcanic clouds using AVHRR bands 4 and 5, Jour. Geophys. Res., 99: 5421-5431.
3267 --- Eruption Cloud Location and Ash Burden
William I. Rose, e-mail: raman#mtu.edu (change # to @ to break SPAMblock)
Description: This algorithm will produce maps showing the outline of an eruption cloud at different time steps, similar to what has been done using bands 4 and 5 of AVHRR. The maps will be color-contoured, with color keyed to the ash loading mass per km2, assuming a uniform size distribution of ash. The current algorithm is valid for semitransparent eruption clouds in which most of the particles are silicate ash. The spatial resolution will be 1 km.
Input: MODIS Level 1B radiance data (MOD02), channels 31 and 32.
Output from Mich. Tech. Univ. SCF (HDF File Format, No Browse Images Available): 8-bit color raster maps depicting plume boundary and ash burden at different times, typically 3 maps per eruption, 5 eruptions per year, 500 km x 500 km area per map, 0.5 Mb each map, approximately 15 maps/yr. Ancillary information provided with these maps will include the temperature of the volcanic cloud top and of the underlying surface.
Software to be made available: User-interactive software package (Radiannet) written in IDL (Interactive Data Language) for creating eruption cloud location and ash burden maps from MODIS data. The software will go beyond this and allow the user to make assumptions about the single (or dominant) type of particle in the cloud (ash, H2SO4, ice, or water), the particle size range, and likely particle size distribution, and then create maps of effective particle radius, optical depth, and mass of particles in the cloud.
References: Schneider, DJ, and WI Rose (1994) Observations of the 1989-90 Redoubt Volcano eruption clouds using AVHRR Satellite Imagery, U.S. Geol. Survey Bull., 2047: 405-418; Wen, S, and WI Rose (1994) Retrieval of particle sizes and masses in volcanic clouds using AVHRR bands 4 and 5, Jour. Geophys. Res., 99: 5421-5431; Holasek, RE and WI Rose (1991) Anatomy of 1986 Augustine volcano eruptions as recorded by multispectral image processing of digital AVHRR weather satellite data, Bull. Volcanol., 53: 420-435.
3281 --- Volcanic SO2 - Low Spatial Resolution
Arlin J. Krueger, e-mail: krueger#chapman.gsfc.nasa.gov (change # to @ to break SPAMblock)
Description: This algorithm uses TOMS data (ultraviolet radiance) to determine the spatial distribution of the column abundance of sulfur dioxide and ash in eruption plumes. The TOMS SO2 database started in 1979 suggests that approximately 1 to 12 eruptions will be detected per year (4 eruptions per year on average). The nadir spatial resolution for TOMS is 25 to 60 km, depending on the satellite (Nimbus-7, Meteor 3, ADEOS, Earth Probe). The 3-sigma detection sensitivity is 900 tons SO2 and 1500 tons ash per nadir pixel.
Input: Earth radiance in 6 TOMS UV (308 - 380 nm) channels.
Output from the Goddard EOS Volcanology SCF to the Goddard Distributed Active Archive Center: SO2 and ash maps and raw binary data files (latitude, longitude, time, date, SO2, Aerosol Index, etc.). The number of eruptions detected by TOMS is variable from year to year and the number of days a particular eruption is continuously detected can vary from 1 day to over 1 month. Approximately 26 maps will be produced per year, at 30 to 80 Kb each, and the associated binary data files will require 0.3 to 10.5 Mb each, depending on the size of the eruption cloud.
Software to be made available: Fortran and C programs to read the binary data files.
References: Krotkov, NA, AJ Krueger, and PK Bhartia (1997) Ultraviolet optical model of volcanic clouds for remote sensing of ash and sulfur dioxide, Jour. Geophys. Res., 102: 21891-21904; Krueger, AJ, LS Walter, PK Bhartia, CC Schnetzler, NA Krotkov, I Sprod, and GJS Bluth (1995) Volcanic sulfur dioxide measurements from the Total Ozone Mapping Spectrometer (TOMS) Instruments. Jour. Geophys. Res., 100: 14057 - 14076; Bluth, GJS, CC Schnetzler, AJ Krueger, and LS Walter (1993) The contribution of explosive volcanism to global atmospheric sulfur dioxide concentrations, Nature, 366: 327-329.
3288 --- Eruption Plume SO2 Alert
Joy Crisp, e-mail: joy#glassy.jpl.nasa.gov (change # to @ to break SPAMblock)
Description: The entire MODIS Level 0 data stream will be continuously searched during Level 1A production by the MODIS SCF, using 4 channels in near-real time. The search algorithm will detect large amounts of SO2 at altitudes between about 6 and 25 km. When an alert is triggered, notification will be sent to JPL and Univ. Hawaii SCFs, where alert location and timing maps will be prepared. The alert is expected to be triggered for up to about 3 eruptions per year. The spatial resolution will be 1 km.
Input: Continuous observation of the Level 0 MODIS data stream (Channels 27, 28, 31, and 36) by the MODIS SCF, conducted as part of a collaborative effort with the MODIS Team.
Output from the JPL SCF (HDF File Format, No Browse Images Available):
3289 --- Volcanic SO2 - High and Moderate Spatial
Vince J. Realmuto, e-mail: Vincent.Realmuto#jpl.nasa.gov (change # to @ to break SPAMblock)
Description: This algorithm will use multichannel thermal infrared observations of eruption clouds to map the spatial distribution of sulfur dioxide in an eruption plume, using ASTER (high spatial resolution, 90 m) or MODIS (moderate spatial resolution, 1 km). In addition, a surface temperature map will be produced for each SO2 map.
Input for High Spatial Resolution Products: Level 1B radiance at sensor (AST03), surface radiance (AST09), land surface emissivity (AST05), and land surface kinetic temperature (AST08). Will use an average of twenty-two scenes per year. Best available digital elevation model for each site (AST14), once every 5 years or immediately after an eruption of topographic consequence, whichever period is shorter.
Input for Moderate Spatial Resolution Products: Level 1B radiance (MOD02) and MOD30 profiles.
Input for High & Moderate Resolution Products: Temperature and water vapor profiles from MODIS (MOD30) (12 sets of profiles per scene), or AIRS (AIR07 and AIR05) (4 per scene).
Output from JPL SCF (HDF File Format, No Browse Images Available): 8-bit raster images.
Software to be made available: User-interactive software package (XMAP_SO2) written in IDL (Interactive Data Language) for creating SO2 and temperature maps from ASTER data.
References: Realmuto, VJ, MJ Abrams, MF Buongiorno, and DC Pieri (1994) The use of multispectral thermal infrared image data to estimate the sulfur dioxide flux from volcanoes: A case study from Mount Etna, Sicily, 29 July 1986, Jour. Geophys. Res., 99: 481-488.
3293 --- Plume Top Characteristics
Lionel Wilson, e-mail: L.Wilson#lancaster.ac.uk
Lori S. Glaze, e-mail: lori#puuoo.gsfc.nasa.gov (change # to @ to break SPAMblock)
Description: This algorithm will produce maps of plume top topography from photoclinometry, plume top temperature, and plume top altitude and topography from plume top temperatures using MODIS (and ASTER, when available). The spatial resolution will be 1 km for the maps made from MODIS data, and 90 m for maps from ASTER data. Approximately 5 eruptions will be studied per year.
Input: MODIS Level 1B radiance (MOD02), Channels 12, 17, and 31. About 3 scenes/eruption = 15 scenes/yr. ASTER Level 1B radiance (AST03), three infrared channels, 60 km x 60 km scene, on an as-available basis (probably less than 1 scene/yr). MODIS (MOD30) or AIRS (AIR07) temperature profiles, 3 profiles per MODIS or ASTER scene. Whenever simultaneous observations by MISR are available, cloud top elevation (MIS04, parameter 1433), will be used for comparison with products 3293a and 3293c.
Output from Goddard SCF (HDF File Format, No Browse Images Available): 8-bit raster images.
Software to be made available: User-interactive software package written in IDL (Interactive Data Language) for creating 3-D plots (wire mesh or shaded relief) of plume top topography, color contour maps of plume top temperature, and 3-D plots of plume top altitude and topography from MODIS or ASTER data.
References: Glaze, L.S., L. Wilson, and P.J. Mouginis-Mark, 1999, Volcanic eruption plume top topography and heights as determined from photoclinometric analysis of satellite data, Jour. Geophys. Res., 104:2989-3001; Holasek, RE, and S Self (1995) GOES weather satellite observations and measurements of the May 18, 1980, Mount St. Helens eruption, Jour. Geophys. Res., 100: 8469-8487; Holasek, RE and WI Rose (1991) Anatomy of 1986 Augustine volcano eruptions as recorded by multispectral image processing of digital AVHRR weather satellite data, Bull. Volcanol., 53: 420-435.Go to Part I: Surface Volcanism