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Using the NASA EOSDIS Common Metadata Repository

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  • Antarctic iceberg sizes and spatial distribution from SAR image analysis - Map

    https://cmr.earthdata.nasa.gov/search/concepts/C1214311458-AU_AADC.xml
    Description:

    This map shows the distribution of the iceberg data extracted from ERS SAR images. Icebergs are identified in Synthetic Aperture Radar [SAR] images by image analysis using the texture and intensity of the microwave backscatter observations. The images are segmented using an edge detecting algorithm, and segments identified as iceberg or background, which may be sea ice, open water, or a mixture of both. Dimensions of the icebergs are derived by spatial analysis of the corresponding image segments. Location of the iceberg is derived from its position within the image and the navigation data that gives the location and orientation of the image. More than 20,000 individual observations have been extracted from SAR images acquired by the European Space Agency's ERS-1 and 2 satellites and the Canadian Space Agency's Radarsat satellite. Because images can overlap, some proportion of the observations represent multiple observations of the same set of icebergs. Most observations relate to the sector between longitudes 70E and 135E. The data set includes observations from several other discrete areas around the Antarctic coast. In general observations are within 200 km of the coast but in limited areas extend to about 500 km from the coast. This metadata record has been derived from work performed under the auspices of ASAC project 2187 (ASAC_2187). The map in the pdf file shows the extent of the coverage of individual SAR scenes used in the analysis and the abundance and size characteristics (by a limited colour palette) of the identified icebergs.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -80 70 -55 135

    AU_AADC Short Name: AAD_Ant_iceberg_SAR Version ID: 1 Unique ID: C1214311458-AU_AADC

  • Australian Antarctic Territory Coastline 2003

    https://cmr.earthdata.nasa.gov/search/concepts/C1214305672-AU_AADC.xml
    Description:

    The 'Australian Antarctic Territory coastline 2003' dataset is a digital vector representation of the coastline of Antarctica, between 45 to 160 degrees east, based on both the edge of permanent ice and grounding line, derived by means of remote sensing interpretation. A 'proof of concept' methodology over a test area was carried out to compare a number of complementary remote sensing techniques, including interferometry and airborne ice radar profiling, to confirm validation of grounding line as mapped from Landsat 7 ETM+ imagery. This methodology concept then served to validate grounding line locations elsewhere along the coast of the AAT. The National Mapping Division of Geoscience Australia and the Australian Antarctic Division developed this dataset as a joint project. Where available, Australian Antarctic Division supplied large-scale vector data of various areas around the AAT, which were included as part of the main coastline dataset. These included: * Holme Bay 1:25,000 GIS dataset * Larsemann Hills - Mapping from aerial photography captured February 1998 * Rauer Group 1:50000 Topographic GIS Dataset * Vestfold Hills Topographic GIS Dataset * Windmill Islands 1:50000 Topographic GIS Dataset * Cape Denison and McKellar Islands GIS dataset from Ikonos satellite imagery Refer to the metadata record for each of these datasets for further information. The coastline dataset is comprised of three parts: one polygon coverage consisting of ice features, and another one consisting of coastal features. A third coverage consists of only island point features (islands too small to be shown as polygons). This dataset supersedes the Australian Antarctic Territory Coastline 2001 dataset which is also part of SCAR's Antarctic Digital Database (ADD) version 4 and version 5. It replaces data digitised from Landsat 4 and 5, with that from Landsat 7 ETM+, because of its more reliable positional accuracy and more recent acquisition. The Australian Antarctic Territory Coastline 2001 dataset and metadata record have been archived. Please contact the Australian Antarctic Data Centre if you would like a copy of this data and metadata.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -82.679 42.723 -64.929 169.333

    AU_AADC Short Name: AAT_Coastline_2003 Version ID: 1 Unique ID: C1214305672-AU_AADC

  • Fast-ice Distribution in East Antarctica During 1997 and 1999 Determined Using RADARSAT Data

    https://cmr.earthdata.nasa.gov/search/concepts/C1214308565-AU_AADC.xml
    Description:

    An image correlation technique has been applied to RADARSAT ScanSAR images from November in 1997, and November 1999, to create the first detailed maps of fast ice around East Antarctica (75E-170E). This method is based upon searching for, and distinguishing, correlated regions of the ice-covered ocean which remain stationary, in contrast to adjacent moving pack ice. Within the overlapping longitudinal range of ~86E-150.6E, the total fast-ice area is 141,450 km2 in 1997 and 152,216 km2 in 1999. Calibrated radar backscatter data are also used to determine the distribution of two fast-ice classes based on their surface roughness characteristics. The outer boundaries of the determined fast-ice area for November in 1997 and 1999 are contained in the data files for this record. This work has been allocated to ASAC project 3024.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -70 75 -55 170

    AU_AADC Short Name: fast_ice_1997_1999 Version ID: 1 Unique ID: C1214308565-AU_AADC

  • Heard Island RADARSAT (1997) Digital Elevation Model (DEM)

    https://cmr.earthdata.nasa.gov/search/concepts/C1214313515-AU_AADC.xml
    Description:

    A Digital Elevation Model (DEM) of Heard island, with a 50 metre grid interval, and held in UTM Zone 43(WGS-84) coordinates. Heights are referenced to mean sea level. 50 metre contours (including a coastline) were derived. Elevation range 0 - less than 2800m.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -53.2 73.238 -52.957 73.89

    AU_AADC Short Name: heard_dem_radarsat97 Version ID: 1 Unique ID: C1214313515-AU_AADC

  • Heard Island RADARSAT (2002) Digital Elevation Model (DEM)

    https://cmr.earthdata.nasa.gov/search/concepts/C1214308612-AU_AADC.xml
    Description:

    This dataset is a Digital Elevation Model (DEM) of Heard Island derived by interferometric processing from RADARSAT images acquired on 17 February 2002 and 13 March 2002. The DEM was created by a contractor for the Australian Antarctic Data Centre. The cell size is 10 metres. Processing stages included: 1 Detection of a coastline from a RADARSAT image of Heard Island acquired 24 January 2002 and rectified using ground control points provided by a second contractor. 2 Generation of the interferometric SAR (InSAR) DEM using the RADARSAT images acquired on 17 February 2002 and 13 March 2002. 3 Co-registration of the InSAR DEM with a DEM derived from stereoscopic RADARSAT images acquired in March and April of 1997 and described by the metadata record 'Heard Island RADARSAT (1997) DEM'. 4 Merging of the InSAR DEM with the 1997 stereoscopic DEM and the coastline detected in stage 1. The following are available for download from the Related URLs below: 1 The final DEM in ArcInfo interchange or ArcInfo ascii formats. 2 The rectified RADARSAT image of Heard Island acquired 24 January 2002. Rectified using ground control points and subsequently used in processing of the DEM. 3 Contours generated from the DEM and the island polygon (coastline) extracted from the rectified RADARSAT image acquired 24 January 2002. 4 A detailed deport describing the generation of the DEM. 5 A report by Dr Arko Lucieer Centre for Spatial Information Science School of Geography and Environmental Studies University of Tasmania Private Bag 76 Hobart 7001 Tasmania, Australia outlining some errors and artefacts in the DEM. Dr Lucieer produced this report while working for the Australian Antarctic Division. On 3 July 2003 Henk Brolsma (Mapping Officer, Australian Antarctic Division) wrote the following email to the contractor who created the DEM. "What I'm really interested in are the 20 metre contours for the areas with high coherency. These are the areas where most of the field work takes place and where we have a need for contours with an accuracy better than 50 metres and my reason for using INSAR in the first instance. So can you send me: 1. The 20 metre contours for the areas with high coherency? 2. The zone or line where the INSAR and Stereo Imagery were integrated? This would be very useful for the metadata." He did not receive a reply to that email and that was the reason why he was reluctant to make the DEM public. Since he won't now get a reply and the DEM is probably better than the 1997 DEM, he considers the 2002 DEM should now be published.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -53.27694 73.18306 -52.80806 73.97306

    AU_AADC Short Name: heard_dem_radarsat02 Version ID: 1 Unique ID: C1214308612-AU_AADC

  • Heard Island Radarsat Georeferencing Report, September 2002

    https://cmr.earthdata.nasa.gov/search/concepts/C1214313518-AU_AADC.xml
    Description:

    The aim of the project was to derive a number of control points that could be used to georeference two Radarsat scenes over Heard Island. Control points were derived from aerial photography covering various locations around the island, namely: Cape Gazert, Atlas Cove, Brown Lagoon, Manning Lagoon and Winston Lagoon. ERDAS Imagine with OrthoBase Pro photogrammatric software was used to ortho-rectify the aerial photography and extract values for the derived control points. ERDAS Imagine OrthoRadar was used to georeference the Radarsat images. The measurements taken from the aerial photography have been described in an earlier report.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -53.21 73.24 -52.95 73.9

    AU_AADC Short Name: Heard_RadarSat_georef Version ID: 1 Unique ID: C1214313518-AU_AADC

  • Heard Island, Laurens Peninsula, Coastal Orthophoto Mosaic derived from Non-Metric Photography

    https://cmr.earthdata.nasa.gov/search/concepts/C1214311224-AU_AADC.xml
    Description:

    The orthophoto mosaic is a rectified georeferenced image of the Heard Island, Laurens Peninsula Coastal Area. Distortions due to relief and tilt displacement have been removed. Orthophotos were derived from non-metric cameras (focal length unknown).

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -53.05 73.23 -52.95 73.41

    AU_AADC Short Name: photo_mosaic_laurens_or Version ID: 1 Unique ID: C1214311224-AU_AADC

  • Heard Island, Laurens Peninsula, Topographic Mapping from Orthophoto Mosaic derived from Non-Metric Photography

    https://cmr.earthdata.nasa.gov/search/concepts/C1214311225-AU_AADC.xml
    Description:

    The Heard Island, Laurens Peninsula, Topographic Data was mapped from Ortho-rectified non-metric photography. The data consists of Coastline, Crater, Volcano, Island, Lagoon, Water Storage and Watercourse datasets digitised from the photography.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -53.05 73.23 -52.95 73.41

    AU_AADC Short Name: photo_mosaic_laurens_or_TopoMapping Version ID: 1 Unique ID: C1214311225-AU_AADC

  • Hurricane Katrina Imagery from Louisiana State University Earth Scan Laboratory

    https://cmr.earthdata.nasa.gov/search/concepts/C1214621393-SCIOPS.xml
    Description:

    The Louisiana State University Earth Scan Laboratory will continue to provide satellite imagery, analysis, and information as rapidly as possible of Hurricane Katrina and her aftermath. The Earth Scan Laboratory has served the the emergency relief efforts, state-wide, and at the LOHSEP since before Katrina made landfall, and, will continue to provide satellite-based analysis and operational support throughout the recovery effort. Hurricane Katrina's Aftermath is being monitored, and studied with satellite imagery acquired at the ESL, and obtained from outside sources. Links to other sites related to the post-storm analysis are also provided.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 28 -92 32 -86

    SCIOPS Short Name: LSU_ESL_KATRINA_IMAGERY Version ID: Not provided Unique ID: C1214621393-SCIOPS

  • Ice velocity and strain rate fields over the Lambert Glacier - Amery Ice Shelf system, East Antarctica

    https://cmr.earthdata.nasa.gov/search/concepts/C1214305517-AU_AADC.xml
    Description:

    Measurements of ice velocity and strain rate have been derived by analysis of satellite images for the Lambert Glacier and Amery Ice Shelf system. Two techniques have been applied in the production of the two main sets of velocity values. One technique uses 'feature tracking' in pairs of Landsat TM images. This process uses surface features that persist with time and move with the ice as tracers of the ice motion. The displacement of these features over the time interval between acquisition of the two images in a pair is determined by image correlation. A reference sub-image is extracted from one image and the best correlation is searched for in the other image. The pair of images were registered by comparing fixed features such as rock outcrops or areas of known ice velocity. The analysis is carried at regular increments across and along the images, to produce a regular grid of values. The derived values are edited and accepted according to whether they satisfy certain a priori constraints for the flow in a local region and the statistics of a set of velocity values within a window. The TM images have been pre-processed to project them onto a common reference and projection system, and spliced together, in order to produce a seamless set of velocity values. Many tens of thousands of observations have been extracted along the entire length of the system (about 600+ km). The other technique has been applied to analysis of Synthetic Aperture Radar images. It uses a procedure applied during SAR interferometry [InSAR] to register small sections of the SAR complex image for generation of the phase difference or fringe image. The process we have applied uses maximum coherence as a test for best match or correlation of two image chips extracted from a pair of coherent complex SAR images. This procedure uses the phase information inherent in the SAR data in place of features as used for the TM analysis. From this analysis a set of displacements is derived comparable to the results for feature tracking. The displacements are derived in the range coordinate system of the complex SAR images. The displacements are converted to velocity values in the ground coordinate system. Corrections are also applied at this stage to allow for errors in the satellite orbits for the two sets of SAR acquisitions. One velocity data set derived from analysis of SAR data from the Canadian Space Agency's Radarsat covers an 800 km length of the system. Further data are being extracted by InSAR analysis of SAR data from the European Space Agency's ERS tandem mission. Horizontal components of strain rate are derived from the velocity data using a set of derivative operators in a least-squares solution of an over-constrained set of equations, which uses all velocity values within a computation window. This procedure effectively produces a set of average velocity and strain rate values and accounts for much of the 'noise' in the individual velocity observations. Values of the local longitudinal, transverse and shear strain rate components are derived by rotation of the cartesian values to the local flow direction. This metadata record has been derived from work performed under the auspices of ASAC project 2224 (ASAC_2224).

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -76 60 -69 75

    AU_AADC Short Name: AAD_Ant_LG-AIS_vel_strain Version ID: 1 Unique ID: C1214305517-AU_AADC