1. ICESat/GLAS Tools at NSIDC Melinda Marquis NSIDC Product Team Lead, AMSR-E and GLAS Feb. 16, 2005

2. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 2 Outline: ICESat/GLAS Tools GLAS on ICESat. Graphic is courtesy of Ball Aerospace. IDL Visualizer NSIDC GLAS Altimetry elevation extractor Tool (NGAT) IDL Readers Fortran 90 Readers IDL Ellipsoid Conversion tool ICESat/GLAS Subsetter GLAS Tools Page at http://nsidc.org/data/icesat/tools.html http://nsidc.org/data/icesat/tools.html

3. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 3 IDL Visualizer  Reads data from an ICESat/GLAS file and views graphical summaries of variables.  A quick-start tutorial is available on-line to help users get started viewing ICESat/GLAS data.  SCF responded to NSIDC’s request that this package be made to work with the free IDL Virtual Machine (Jan. 2005).  Developed by the GLAS SCF.

4. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 4 IDL Visualizer

5. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 5 IDL Visualizer

6. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 6 NSIDC GLAS Altimetry elevation extractor Tool (NGAT)  Extracts elevation and geoid data from GLAS altimetry products (GLA06 and GLA12-15) and outputs latitude, longitude, elevation, and geoid in ASCII columns.  The NGAT runs under IDL (6.0 or greater) or the free IDL Virtual Machine (IDLVM) available from Research Systems Inc.  Developed by NSIDC (Matt Savoie).

7. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 7 NSIDC GLAS Altimetry elevation extractor Tool (NGAT) 372402615 03/07/2004 00:31:01.540 61.775047 213.540418 562.026 18.440000 372402615 03/07/2004 00:31:01.565 61.776580 213.539815 561.983 18.434615 372402615 03/07/2004 00:31:01.590 61.778114 213.539224 562.099 18.429231 372402615 03/07/2004 00:31:01.615 61.779650 213.538645 562.267 18.423846 372402615 03/07/2004 00:31:01.640 61.781187 213.538080 562.097 18.418462 372402615 03/07/2004 00:31:01.665 61.782726 213.537528 562.012 18.413077 Record No. Date Time Lat. (deg.) Long. (deg.) Elevation (m) Geoid (m)

8. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 8 IDL Readers  Read data from an ICESat/GLAS file and prints all the variables in ASCII format.  The readers run under IDL (6.0 or greater) or the free IDL Virtual Machine (IDLVM) available from Research Systems, Inc.  Developed by the GLAS SCF.

9. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 9 IDL Readers

10. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 10 Fortran 90 Readers  This set of programs reads data from an ICESat/GLAS file and prints all the variables in ASCII format (identical output as IDL reader).  This is sample code to help users develop their own applications.  There is a separate program for each product type ("read_glaxx_file") where xx is the product number.

11. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 11 Fortran 90 Readers  The programs are written in Fortan 90 and developed in a HP/UX 11.x runtime environment.  A relatively modern Fortran 90 compiler is required.  Runs on only HP/UX and some Sun platforms.  Developed by the GLAS SCF.

12. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 12 IDL Ellipsoid Conversion tool Converts between the ICESat/GLAS and WGS-84 ellipsoids. ICESat/GLAS geolocated products are given in terms of geodetic latitude, longitude, and height (elevation) above the TOPEX/Poseidon ellipsoid. Three programs convert latitudes and elevations between the WGS-84 and the TOPEX/Poseidon ellipsoids. Developed by NSIDC (Terry Haran).

13. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 13 ICESat/GLAS Subsetter  User enters bounding coordinates and temporal range of interest in a web form on NSIDC’s site.  NSIDC provides the spatially subsetted data.  Developed by NSIDC (Matt Savoie), in conjunction with the GLAS SCF.  NSIDC uses our rSCF (with code dev’d by main SCF) to perform subsetting.

14. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 14 Summary NSIDC has worked with the ICESat/GLAS science team, SCF and SIPS to provide needed tools to the broad user community.  Readers  Visualization tools  Subsetter This collaborative effort benefits users and facilitates use of the ICESat/GLAS data. Thanks go to the science team, SCF, SIPS and NSIDC programmers and staff: John DiMarzio Kris Barbieri Jeff Guerber Jay Zwally David Hancock Anita Brenner Matt Savoie Terry Haran Siri Jodha Singh Khalsa

15. Polar DAAC Advisory Group Melinda Marquis, NSIDC DAACFeb. 16, 2005 15 GLAS Data Products ShortName Longname Received # of Granules Ingested GLA01L1A Global Altimetry Data X 206 GLA02L1A Global Atmosphere Data X 26 GLA03L1A Global Engineering Data X 22 GLA04L1A Global Laser Pointing Data X 22 GLA05L1B Global Waveform-based Range Corrections X 95 GLA06L1B Global Elevation Data X131 GLA07L1B Global Backscatter Data X 6 GLA08L2 Global PBL & Elevated Aerosol Layer Heights X 3 GLA09 L2 Global Cloud Heights for Multi-layer Clouds X 3 GLA10L2 Global Aerosol Vertical Structure Data X 2 GLA11L2 Global Thin Cloud/Aerosol Optical Depths Data X 2 GLA12L2 Global Antarctic & Greenland Ice Sheet Alt. X 2 GLA13L2 Sea Ice Altimetry Data X 2 GLA14L2 Global Land Surface Altimetry Data X 2 GLA15L2 Ocean Altimetry Data X 2 GLA16 is not fully developed