What is HDF-EOS? Information compiled from HDF-EOS Workshop II HDF-EOS Workshop III, 1999

1. What is HDF-EOS?Information compiledfrom HDF-EOS Workshop IIHDF-EOS Workshop III, 1999 ESDIS Project, Code 423 NASA/Goddard Space Flight Center Greenbelt MD 20771 USA

2. HDF-EOS • HDF-EOS defines standard “profiles” for the use of HDF in the domain of Earth Observing Data. • HDF-EOS is a higher level library built on top of HDF structures and functions. • Geolocation information is coupled to data for common data collection profiles of Point, Swath and Grid. HDF-EOS, Ullman

3. HDF-EOS Point • Intended use • Discrete points in time and/or location. • Table of data linked to table of geographic information. • 8-level Hierarchical, each level may contain indices to the level below HDF-EOS, Ullman

4. HDF-EOS Point • Hierarchical links: • Every level in a Point data set must be linked into the hierarchy. • Before two levels can be linked, a link field must exist HDF-EOS, Ullman

5. HDF-EOS Point • No presently defined data sets from Landsat or Terra instruments. • Likely use in validation campaigns. HDF-EOS, Ullman

6. HDF-EOS Swath • Intended use • Across track scanning instruments. • Sounding instruments • Level 1: Geolocated Sensor Units • Level 2: Geophysical Parameters derived from Level 1. HDF-EOS, Ullman

7. Dimension Name: Scan Size: 16 Dimension Name: Track Size: 42 Map1 DataDimension: “Track” Geodimension: “Geotrack” Offset: 1 Increment: 2 HDF-EOS Swath Geolocation fields Data fields “Brightness Temperature” “Time” Dimension Name: Geotrack Size: 21 “Latitude” “Longitude” HDF-EOS, Ullman

8. HDF-EOS Swath • 74 HDF-EOS Swath Products are defined for distribution from EOSDIS after Terra launch. • ASTER, CERES, Landsat 7, MISR, MODIS and MOPITT HDF-EOS, Ullman

9. HDF-EOS Grid • Intended use • Variables mapped on uniform space-time grid scales • Level 3 - Gridded single measurement parameters • Level 4 - Modeled or derived from multiple measurements HDF-EOS, Ullman

10. Xdim Size: 2000 Projinfo Ydim Size: 800 Altitude Size 30 HDF-EOS Grid HDF-EOS, Ullman

11. Projections Supported Geographic Transverse Mercator Universal Transverse Mercator Hotine Oblique Mercator Space Oblique Mercator Polar Stereographic Lambert Azimuthal Equal Area Lambert Conformal Conic Polyconic Interrupted Goode’s Homolosine Integerized Sinusoidal Compression Methods Run-Length Encoding Adaptive Huffman Gzip HDF-EOS Grid HDF-EOS, Ullman

12. HDF-EOS Grid • 128 HDF-EOS Grid Products are defined for distribution from EOSDIS after Terra launch. • ASTER, CERES, ECS Ancillary, MISR, MODIS, MOPITT HDF-EOS, Ullman

13. Level 0 - Reconstructed, unprocessed instrument/pay-load data at full resolution; any and all communications artifacts, e.g., synchronization frames, communications headers, duplicate data removed. Level 1A- Reconstructed, unprocessed instrument data at full resolution, time-referenced, and annotated with ancillary information, including radiometric and geometric calibration coefficients and georeferencing parameters, e.g., platform ephemeris, computed and appended but not applied to the Level 0 data. Level 1B - Level 1A data that have been processed to sensor units (not all instruments will have a Level 1B equivalent). Level 2 - Derived geophysical variables at the same resolution and location as the Level 1 source data. Level 3 - Variables mapped on uniform space-time grid scales, usually with some completeness and consistency. Level 4 - Model output or results from analyses of lower level data, e.g., variables derived from multiple measurements. Product Levels HDF-EOS, Ullman

14. An HDF File Key One or more HDF data objects: • Portability • Elementary data access • Basic self-description One or more HDF-EOS data objects: • Geolocation information tightly coupled to data • Fully standardized geographical subsetting • Moderate self-description EOSDIS Metadata ODL in a “text annotation” • ECS ingest, archiving, search, and distribution • Enhanced self-description HDF-EOS, Ullman

15. Services Provided Portability Elementary data access Basic self-description Services Not Provided Geolocation information tightly coupled to the data Fully standardized geographical subsetting ECS ingest, archiving, search, and distribution Enhanced self-description An HDF file with a set of HDF data objects HDF-EOS, Ullman

16. Services Provided Portability Elementary data access Moderate self-description Geolocation information tightly coupled to the data Fully standardized geographical subsetting Services Not Provided ECS ingest, archiving, search, and distribution Enhanced self-description An HDF file with a set of HDF-EOS data objects HDF-EOS, Ullman

17. Services Provided Portability Elementary data access Moderate self-description Geolocation information tightly coupled to some of the data Partially standardized geographical subsetting Services Not Provided ECS ingest, archiving, search, and distribution Enhanced self-description Fully standardized geographical subsetting An HDF file with a mixed set of HDF-EOS and HDF data objects HDF-EOS, Ullman

18. Services Provided Portability Elementary data access ECS ingest, archiving, search, and distribution Enhanced self-description Services Not Provided Geolocation information tightly coupled to the data Fully standardized geographical subsetting An HDF file with a set ofHDF data objects with EOSDIS metadata HDF-EOS, Ullman

19. Services Provided Portability Elementary data access Geolocation information tightly coupled to the data Fully standardized geographical subsetting ECS ingest, archiving, search, and distribution Enhanced self-description Services Not Provided None of the above listed services. An HDF file with a set of HDF-EOS data objects with EOSDIS metadata HDF-EOS, Ullman