GLAH14 GLAS/ICEsat L2 Global Land Surface Altimetry Data (HDF5) Zwally, H., R. Schutz, D. Hancock, and J. Dimarzio. GLAS/ICEsat L2 Global Land Surface Altimetry Data (HDF5) 2012-12-26 Boulder, Colorado USA NSIDC DAAC: NASA DAAC at the National Snow and Ice Data Center 33 http://nsidc.org/data/glah14.html http://dx.doi.org/10.5067/ICESAT/GLAS/DATA207 Technical Contact NSIDC User Services nsidc@nsidc.org 1 303 492-6199 x 1 303 492-2468 x

National Snow and Ice Data Center

CIRES, 449 UCB

University of Colorado

Boulder CO 80309-0449 USA Technical Contact David Hancock David.W.Hancock@nasa.gov

NASA Goddard Space Flight Center

ISIPS Manager

NASA Goddard Space Flight Center

Wallops Flight Facility

Wallops Island, VA

USA

Investigator H. Jay Zwally Jay.Zwally@nasa.gov 1 301 614-5643 1 301 614-5644

NASA/Goddard Space Flight Center

Laboratory for Hydrospheric Processes

NASA/Goddard Space Flight Center

Code 971

Greenbelt MD 20771 USA Investigator H. Jay Zwally Jay.Zwally@nasa.gov 1 301 614-5643 1 301 614-5644

NASA/Goddard Space Flight Center

Laboratory for Hydrospheric Processes

NASA/Goddard Space Flight Center

Code 971

Greenbelt MD 20771 USA Investigator Robert Schutz

University of Texas at Austin

Center for Space Research

GLAS Science Team Lead

University of Texas at Austin

Center for Space Research

Austin TX 78712-1085 USA Investigator John Dimarzio john.dimarzio@gsfc.nasa.gov 1 301 614-5893

NASA/Goddard Space Flight Center

SGT, Inc.

NASA/Goddard Space Flight Center

Cryospheric Sciences Branch Code 614.1

Greenbelt MD 20771 USA EARTH SCIENCE Land Surface Surface Radiative Properties Reflectance Laser Reflectance EARTH SCIENCE Land Surface Topography Terrain Elevation Elevation Atmospheric Delay Correction DAAC Dem EOSDIS GLA14 GLAS Global Positioning System ICESat ISIPS Laser Footprint Laser Pulse NASA Noise Level NSIDC Off-nadir Pointing Direction Orbit Number Peak Amplitude Precision Attitude Determination Precision Orbit Determination Range Received Energy Received Pulse Gain Signal Saturation Solar Incidence Angle Transmitted Energy Transmitted Gain Waveform Waveform Kurtosis Waveform Peak Waveform Skewness ALTIMETERS GLAS Geoscience Laser Altimeter System ICESAT Ice, Cloud and Land Elevation Satellite SATELLITES 2003-02-20 2009-10-11 complete -86 86 -180 180 GEOGRAPHIC REGION GLOBAL ICESAT Ice, Cloud and Land Elevation Satellite Each data granule has associated browse products that users can quickly view to determine the general quality of the data in the granule. Altimeter Frame Quality Flag is included in file level global attributes and includes a corrections flag. Indicates if all data in frame are good with appropriate corrections applied; or if some of data are not corrected or have measurement problems. English NASA/GSFC/EOS/EO NSIDC_DAAC NASA DAAC at the National Snow and Ice Data Center http://nsidc.org/daac/index.html Data Center Contact NSIDC User Services nsidc@nsidc.org 1 303 492-6199 1 303 492-2468

National Snow and Ice Data Center

CIRES, 449 UCB

University of Colorado

Boulder CO 80309-0449 USA NSIDC National Snow and Ice Data Center http://nsidc.org Data Center Contact NSIDC User Services nsidc@nsidc.org 1 303 492-6199 1 303 492-2468

National Snow and Ice Data Center

CIRES, 449 UCB

University of Colorado

Boulder CO 80309-0449 USA FTP 167 MB HDF Bae, S. and B.E. Schutz. 2002. Precision attitude determination (PAD). GLAS algorithm theoretical basis document. Version 2.2. Austin, TX: Center for Space Research, University of Texas at Austin. Brenner, A.C., C.R. Bentley, B.M. Csatho, D.J. Harding, M.A. Hofton, J. Minster, L. Roberts, J.L. Saba, R. Schutz, R.H. Thomas, D. Yi, and H.J. Zwally. 2000. Derivation of range and range distributions from laser pulse waveform analysis for surface elevations, roughness, slope, and vegetation heights. Algorithm theoretical basis document. Version 3.0. Greenbelt, MD: Goddard Space Flight Center. Center for Space Research. 'ICESat/GLAS.' January 2002. http://www.csr.utexas.edu/glas/. Davis C.H. and H.J. Zwally. 1993. Geographic and seasonal variations in the surface properties of the ice sheets by satellite radar altimetry. Journal of Glaciology 39:687-697. Earth Science Data and Information System (ESDIS). 1996. EOS Ground System (EGS) Systems and Operations Concept. Greenbelt, MD: Goddard Space Flight Center. Farrell, W.E. 1972. Deformation of the Earth by surface loads. Review of Geophysics and Space Physics 10: 761-797. GLAS Science Team. 2000. Mission Operations Requirement Document (MORD) for the Ice, Cloud and Land Elevation Satellite (ICESat) Mission. Greenbelt, MD: Goddard Space Flight Center. GLAS Science Team. 1997. GLAS Science Requirements. Version 2.01. Greenbelt, MD: Goddard Space Flight Center. Heroux, D. 2000. Progress report on GLAS interface effort with ECS NOSE. Rev. 29 December 2000. Landover, MD: Emergent-IT/Raytheon. Herring, T.A. and K. Quinn. 1999. Atmospheric delay correction to GLAS laser altimeter ranges. GLAS algorithm theoretical basis document. Version 1.0. Lanham, MD: Science Systems and Applications, Inc. Jester, P., and D. Hancock. 2002. The Algorithm Theoretical Basis Document for Level 1A Processing, Version 1.2. Wallops Island, VA: Raytheon ITSS. Jester, P., and J. Lee. 2002. GLAS standard data products specification - level 1. Version 6.0. Wallops Island, VA: Raytheon ITSS. Lee, J. 2002. GSAS user's guide: Version 4.0. Wallops Island, VA: Raytheon ITSS. McGarry, J.F., J. Abshire, X. Sun, J. Saba, A. Brenner, and D. Yi. 2002. GLAS flight science data selection algorithms for the altimeter (1064 nm), Version 4.15. Unpublished report. Rim, H., and B. Schutz. 2002. Precision orbit determination. GLAS algorithm theoretical basis document. Version 2.2. Austin, TX: Center for Space Research, University of Texas at Austin. Schutz, B. 2000. GLAS altimeter post-launch calibration/validation plan. Version 0.99. Austin, TX: Center for Space Research, University of Texas at Austin. Schutz, B. 2002. Laser footprint location (geolocation) and surface profiles. GLAS algorithm theoretical basis document. Version 3.0. Austin, TX: Center for Space Research, University of Texas at Austin. Wahr, J., D. Wingham, and C. Bentley. 2000. A method of combining ICESat and GRACE satellite data to constrain Antarctic mass balance. Journal of Geophysical Research 105(B7):16,279-16,294. Yi, D., J. Minster, and C. Bentley. 1999. Ocean tidal loading corrections. GLAS algorithm theoretical basis document. Version 1.0. Greenbelt, MD: Goddard Space Flight Center. Zwally, H.J., B. Schutz, W. Abdalati, J. Abshire, C. Bentley, A. Brenner, J. Bufton, J. Dezio, D. Hancock, D. Harding, T. Herring, B. Minster, K. Quinn, S. Palm, J. Spinhirne, and R. Thomas. 2002. ICESAT's laser measurements of polar ice, atmosphere, ocean, and land. Journal of Geodynamics 34: 405-445. Zwally, H.J., B. Schutz, D. Hancock, and A. Brenner. 2000. ICESat/GLAS Standard Data Products in HDF and SCF Formats. Version 1.2. Greenbelt, MD: Goddard Space Flight Center. Zwally, H.J., R.A. Bindschadler, A.C. Brenner, T.V. Martin, and R.H. Thomas. 1983. Surface elevation contours of Greenland and Antarctic ice sheets. Journal of Geophysical Research 88(C3):1589-1596.

GLAH06 is used in conjunction with GLAH05 to create the Level-2 altimetry products. Level-2 altimetry data provide surface elevations for ice sheets (GLAH12), sea ice (GLAH13), land (GLAH14), and oceans (GLAH15). Data also include the laser footprint geolocation and reflectance, as well as geodetic, instrument, and atmospheric corrections for range measurements. The Level-2 elevation products, are regional products archived at 14 orbits per granule, starting and stopping at the same demarcation (± 50° latitude) as GLAH05 and GLAH06. Each regional product is processed with algorithms specific to that surface type. Surface type masks define which data are written to each of the products. If any data within a given record fall within a specific mask, the entire record is written to the product. Masks can overlap: for example, non-land data in the sea ice region may be written to the sea ice and ocean products. This means that an algorithm may write the same data to more than one Level-2 product. In this case, different algorithms calculate the elevations in their respective products. The surface type masks are versioned and archived at NSIDC, so users can tell which data to expect in each product. Each data granule has an associated browse product.

VIEW PROJECT HOME PAGE http://icesat.gsfc.nasa.gov/ ICESat/GLAS web site at NASA Goddard Space Flight Center VIEW PROJECT HOME PAGE http://glas.wff.nasa.gov/ ICESat/GLAS web site at NASA Wallops Flight Facility VIEW PROJECT HOME PAGE http://www.csr.utexas.edu/glas/ ICESat/GLAS web site at University of Texas VIEW RELATED INFORMATION http://nsidc.org/data/icesat/index.html ICESat/GLAS Data at NSIDC VIEW RELATED INFORMATION http://nsidc.org/data/dems/index.html Polar Ice Sheet DEMs and Elevation Data USA/NASA CEOS IDN DIF 9.7 2012-12-26 2013-03-06 Updated Version Summary.