This data set contains polygons of glacial lake extent on a near-global scale, averaged over five multi-year periods between 1990 and 2018.

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NSIDC_CPRD Short Name: HMA_GLI Version ID: 1 Unique ID: C3249539102-NSIDC_CPRD

This data set, part of NASA's Making Earth System Data Records for Use in Research Environments (MEaSUREs) Program, consists of ice velocities at 240 m resolution, generated from Landsat 4, 5, 7, and 8 optical image pairs. Velocities were derived using the autonomous Repeat Image Feature Tracking algorithm (autoRIFT) processing chain. Data are available for all land ice areas larger than 5 square km, spanning the period from 1985 to 2018 (subject to image availability and quality). Data scarcity and/or low radiometric quality are significant limiting factors for many regions during the earlier years of the data record. Annual, global coverage is nearly complete after the 2013 launch of Landsat 8.

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NSIDC_CPRD Short Name: NSIDC-0775 Version ID: 1 Unique ID: C3291016291-NSIDC_CPRD

The NASA Making Earth System Data Records for Use in Research Environments ([MEaSUREs](https://earthdata.nasa.gov/about/competitive-programs/measures)) Global Web-Enabled Landsat Data Monthly (GWELDMO) Version 3.1 data product provides Landsat data at 30 meter (m) resolution for terrestrial non-Antarctica locations over monthly reporting periods for the 1985, 1990, and 2000 epochs. GWELD data products are generated from all available Landsat 4 and 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) data in the U.S. Geological Survey (USGS) Landsat archive. The GWELD suite of products provide consistent data to derive land cover as well as geophysical and biophysical information for regional assessment of land surface dynamics. The GWELD products include Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectance (NBAR) for the reflective wavelength bands and top of atmosphere (TOA) brightness temperature for the thermal bands. The products are defined in the Sinusoidal coordinate system to promote continuity of NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) land tile grid. Provided in the GWELDMO product are layers for surface reflectance bands 1 through 5 and 7, TOA brightness temperature for thermal bands, Normalized Difference Vegetation Index (NDVI), day of year, ancillary angle, and data quality information. A low-resolution red, green, blue (RGB) browse image of bands 5, 4, 3 is also available for each granule. Known Issues * GWELDMO known issues can be found in Section 4 of the Algorithm Theoretical Basis Document (ATBD).

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LPCLOUD Short Name: GWELDMO Version ID: 031 Unique ID: C2763268458-LPCLOUD

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).

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• AAD_Ant_LG-AIS_vel_strain

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

Landsat imagery at the University of Alaska's Geophysical Institute includes data covering Alaska and the surrounding areas since 1972. The collection is comprised primarily of Multispectral Scanner System (MSS) data, although data from the Return Beam Vidicon (RBV) and Thematic Mapper (TM) are also included. The MSS provides repetitive acquisition of high-resolution multispectral data of the earth's surface on a global basis. This sensor package images a 100 nautical mile (185 km) wide swath directly below the satellite as it passes over the Earth. Each scene, or frame of data, covers an area 100 by 100 n. miles in size. The nominal size of a pixel (picture element) for this sensor is 80 meters on a side. Four separate bands (wavelengths) are recorded by the MSS: Green 0.5-0.6 microns Red 0.6-0.7 microns Near IR1 0.7-0.8 microns Near IR2 0.8-1.1 microns Initially data were acquired directly from NASA, and were a subset of the holdings of the EROS Data Center in Sioux Falls, South Dakota. Starting in 1978, additional images were acquired from the Canadian Centre for Remote Sensing. From 1982 to 1991, most of the coverage was acquired by the Geophysical Institute Quick Look Project, which operated recording equipment at the NOAA Gilmore Tracking Station near Fairbanks. Scenes in the database that were acquired by the Quick-Look program are so indicated. Much of this data IS NOT in the EROS Data Center's data base and is therefore UNIQUE to this collection. TM and RBV data included in the collection originally came from NASA, the EROS Data Center or EOSAT, depending on the time of acquisition. Their characteristics are described in the references listed for the collection.

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SCIOPS Short Name: ALI Version ID: Not provided Unique ID: C1214592988-SCIOPS