Data Product Summaries Part I: Surface Volcanism

SCF = Science Computing Facility

Product Number --- Product Name (Key Responsible Team Member)

3266 --- Lava-Flow Area Change
Howard Zebker, e-mail: zebker#ee.stanford.edu
Peter J. Mouginis-Mark, e-mail: pmm#kahana.pgd.hawaii.edu (change # to @ to break SPAMblock)

Description: This algorithm will take two raw radar signal data sets, acquired at different times during the emplacement of an active lava flow, and will produce an image data file indicating the correlation between the two images. This will highlight the outline (areal extent) of new lava deposited in a flow. Flow areas and changes in area (rate) will be listed in a table, and the description documented in a text file. The spatial resolution will be about 30 to 50 m. Approximately 10 flows per year will be studied like this.

Input: Raw radar signal samples from a series of radar passes over an active lava flow using ERS-1/2, JERS 1/2, RADARSAT, or ENVISAT ASAR, and platform orbit location data.

Output from Stanford and Univ. Hawaii SCFs (HDF File Format, No Browse Images Available):

• (3266a) 10 correlation image files per year, 1 Mb/file
• (3266b) Area time-series listing, 5 lists/yr x 10 kb/list
• (3266c) Descriptive text file, 10 Mb/yr

References: Zebker, HA, P Rosen, S Hensley, and PJ Mouginis-Mark (1996) Analysis of active lava flows on Kilauea volcano, Hawaii, using SIR-C radar correlation measurements, Geology, 24: 495-498; Zebker, HA, CL Werner, P Rosen, and S Hensley (1994) Accuracy of topographic maps derived from ERS-1 interferometric radar, IEEE Trans. Geosci. and Rem. Sen., 32: 823-836; Madsen, SN, HA Zebker, and J Martin (1993) Topographic mapping using radar interferometry: processing techniques, IEEE Trans. Geosci. Rem. Sens., 31: 246-256; Zebker, HA and J Villasenor (1992) Decorrelation in interferometric radar echoes, IEEE Trans. Geosci. Rem. Sens., 30: 950-959.

3269 --- Volcano Topography
Howard Zebker, e-mail: zebker#ee.stanford.edu
Peter J. Mouginis-Mark, e-mail: pmm#kahana.pgd.hawaii.edu (change # to @ to break SPAMblock)

Description: This algorithm will produce digital topographic maps and corresponding radar backscatter images of volcanoes using repeat-pass interferometric synthetic aperture radar data. About 15 volcanoes per year will be studied this way. The spatial resolution of the digital elevation models will be about 30 to 50 m, and vertical resolution about 2 to 10 m. In addition, digital elevation models of volcanoes will be extracted from SRTM (Shuttle Radar Topography Mission) world digital topography beginning in the year 2000, and will be inserted into the data base.

Input: Raw radar signal samples from a series of radar passes over a volcano, using ERS-1/2, JERS 1/2, RADARSAT, or ENVISAT ASAR, and platform orbit location data, plus DEM data derived from the SRTM mission in 2000.

Output from Stanford and Univ. Hawaii SCFs (HDF File Format, No Browse Images Available):

• (3269a) 15 sets of digital elevation and backscatter images per year, 10 Mb/set.
• (3269b) Height error map, 15 maps per year, 2.5 Mb/map.
• (3269c) Descriptive text file to document the algorithm, one file per year, typically 1 Mb/yr up to a maximum of 10 Mb/yr.

References: Zebker, HA, CL Werner, P Rosen, and S Hensley (1994) Accuracy of topographic maps derived from ERS-1 interferometric radar, IEEE Trans. Geosci. and Rem. Sen., 32: 823-836; Madsen, SN, HA Zebker, and J Martin (1993) Topographic mapping using radar interferometry: processing techniques, IEEE Trans. Geosci. Rem. Sens., 31: 246-256.

3272 --- Volcano Deformation and Change
Howard Zebker, e-mail: zebker#ee.stanford.edu
Peter J. Mouginis-Mark, e-mail: pmm#kahana.pgd.hawaii.edu (change # to @ to break SPAMblock)

Description: This algorithm will generate a topographic difference map from pairs of interferometric radar images, for study of ground deformation and calculation of the thickness of new lava flows. Approximately 5 volcanoes per year will have ground deformation sufficiently large to warrant this type of observation. The spatial resolution will be about 30 to 50 m, and vertical resolution about 2 to 10 m.

Input: Raw radar signal samples from a series of radar passes over a volcano, using ERS-1/2, JERS 1/2, RADARSAT, or ENVISAT ASAR, and platform orbit location data.

Output from Stanford and Univ. Hawaii SCFs (HDF File Format, Browse Images Available for 3272a Only):

• (3272a) Topographic deformation data files, 15 files per year, 11 Mb per file.
• (3272b) Backscatter and correlation ancillary data, 15 data sets, 2.5 Mb each.
• (3272c) Descriptive text file to document the algorithm, up to 10 Mb/yr.

References: Peltzer, G, P Rosen, F Rogez, and K Hudnut (1996) Postseismic rebound in fault step-overs caused by pore fluid flow, Science, 273: 1202-1204; Massonnet, D, P Briole, and A Arnaud (1995) Deflation of Mount Etna monitored by spaceborne radar interferometry, Nature 375: 567-70; Zebker, HA, CL Werner, P Rosen, and S Hensley (1994) Accuracy of topographic maps derived from ERS-1 interferometric radar, IEEE Trans. Geosci. and Rem. Sen., 32: 823-836; Madsen, SN, HA Zebker, and J Martin (1993) Topographic mapping using radar interferometry: processing techniques, IEEE Trans. Geosci. Rem. Sens., 31: 246-256.

3290 --- Surface Thermal Alert
Luke Flynn, e-mail: flynn#waterloo.pgd.hawaii.edu (change # to @ to break SPAMblock)

Description: The entire MODIS Level 1B nighttime data stream will be continuously searched during Level 2 production by the MODIS SCF in near-real time, using 5 bands. Data for alerts that are triggered will be sent to the Univ. Hawaii SCF. The alert fields will be viewed using a limited interactive display on a Web-site, which will allow display of regional or global maps showing locations of alerts and indicating type (volcano/non-volcano) and severity by color or gray-scale differences. The spatial resolution will be 1 km.

Input: Continuous observation of the MODIS Level 1B nighttime data stream by the MODIS SCF, conducted as part of a collaborative effort with the MODIS Science Data Support Team. The alert files will be sent directly from the MODIS SCF to the Univ. Hawaii SCF, where the classification of alerts will be done. The input for alerts will be Channels 21, 22, 29, 31, and 32.

Output from the Univ. Hawaii SCF (HDF File Format, Special Browse Available):

• (3290a) Nighttime Alert, ready 6/98
  Alert files will be approximately 50 bytes per record (HDF binary) containing date, time, latitude, longitude, 5 DN values of alert data, an alert qualifier (volcano/non-volcano, severity), and version number of the nighttime alert software. One MODIS global pass per 24 hours will yield on the order of 10,000 alerts/night from alerted locations. Alerts of up to 1 week old will be located on a Web-site maintained by the EOS Volcanology IDS Team. Within two days of final processing at the Hawaii SCF, alert data in 24-hour increments will be moved to the EDC DAAC for archiving. Previous alerts should be available from EDC within 1 week of acquisition, and users will be able to access archived data through queries of latitude, longitude, and date.
• (3290b) Daytime Alert, not be ready until a year or two after AM-1 launch, depending on the availability of future funding.

References: Flynn, LP, and PJ Mouginis-Mark (1995) A comparison of the thermal characteristics of active lava flows and forest fires, Geophys. Res. Lett., 22: 2577-2580; Flynn, LP, PJ Mouginis-Mark, and KA Horton (1994) Distribution of thermal areas on an active lava flow field: Landsat observations of Kilauea, Hawaii, July 1991, Bull. Volcanol., 56: 284-296.

3291 --- Thermal Anomaly - High Spatial Resolution
Vince J. Realmuto, e-mail: Vincent.Realmuto#jpl.nasa.gov (change # to @ to break SPAMblock)

Description: ASTER radiance data will be used, with careful atmospheric correction, to produce temperature maps of thermal anomalies at 90 m spatial resolution. For the hottest pixels that are saturated in the thermal infrared, spatial resolution may be higher (15 or 30 m). Approximately 3 volcanoes will be routinely monitored at nighttime once every 2 months, and an additional 1 eruption per year may require nighttime observation (up to four extra scenes per eruption).

Input: ASTER Products: Level 1B radiance at sensor (AST03), surface radiance (AST09), land surface emissivity (AST05), and land surface kinetic temperature (AST08), for about 22 ASTER 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. 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): 22 temperature maps/yr, (60 km x 60 km)/map, 0.6 Mb/map (8-bit raster image).

Software to be made available: User-interactive software package written in IDL (Interactive Data Language) for creating temperature maps from ASTER data.

References: Realmuto, VJ, AB Kahle, EA Abbott, and DC Pieri (1992) Multispectral thermal infrared mapping of the October 1, 1988 Kupaianaha flow field, Kilauea Volcano, Hawaii, Bull. Volcanol., 55: 33-44.

3296 --- Volcano Temperature Change
Vince J. Realmuto, e-mail: Vincent.Realmuto#jpl.nasa.gov (change # to @ to break SPAMblock)

Description: Differences two high resolution (ASTER) thermal maps (#3291), which are for the past month and the present month, to produce a map showing change in volcano temperature at 90 m spatial resolution. For the hottest pixels that are saturated in the thermal infrared, spatial resolution may be higher (15 or 30 m).

Input: EOS Volcanology temperature maps (3291).

Output from JPL SCF (HDF File Format, No Browse Images Available): (8-bit raster images) 0.6 Mb/scene x 22 scenes/yr.

Software to be made available: User-interactive software package (XCHANGE2) written in IDL (Interactive Data Language) for creating temperature difference maps from ASTER data. A moving-window algorithm implementing the Student's t test is used to map out the statistically significant changes in temperature for a user-selected window size and confidence level.

References: Realmuto, VJ, AB Kahle, EA Abbott, and DC Pieri (1992) Multispectral thermal infrared mapping of the October 1, 1988 Kupaianaha flow field, Kilauea Volcano, Hawaii, Bull. Volcanol., 55: 33-44.

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