Entry_ID: GLAH12
Entry_Title: GLAS/ICESat L2 Antarctic and Greenland Ice Sheet Altimetry Data (HDF5)
Group: Data_Set_Citation
   Dataset_Creator: Zwally, H., R. Schutz, D. Hancock, and J. Dimarzio. 
   Dataset_Title: GLAS/ICESat L2 Antarctic and Greenland Ice Sheet Altimetry Data (HDF5)
   Dataset_Release_Date: 2014-10-17
   Dataset_Release_Place: Boulder, Colorado USA
   Dataset_Publisher: NSIDC DAAC: NASA DAAC at the National Snow and Ice Data Center
   Version: 34
   Online_Resource: http://nsidc.org/data/glah12.html
   Dataset DOI: http://dx.doi.org/10.5067/ICESAT/GLAS/DATA209
End_Group
Group: Personnel
   Role: Technical Contact
   First_Name: NSIDC
   Last_Name: User Services
   Email: nsidc@nsidc.org
   Phone: 1 303 492-6199 x
   Fax: 1 303  492-2468 x
   Group: Contact_Address
      Address: National Snow and Ice Data Center
      Address: CIRES, 449 UCB
      Address: University of Colorado
      City: Boulder
      Province_or_State: CO
      Postal_Code: 80309-0449
      Country: USA
   End_Group
End_Group
Group: Personnel
   Role: Investigator
   First_Name: David
   Last_Name: Hancock
   Email: David.W.Hancock@nasa.gov
   Group: Contact_Address
      Address: NASA Goddard Space Flight Center
      Address: ISIPS Manager
      Address: NASA Goddard Space Flight Center
      Address: Wallops Flight Facility
      Address: Wallops Island, VA
      Address: USA
   End_Group
End_Group
Group: Personnel
   Role: Investigator
   First_Name: H. Jay
   Last_Name: Zwally
   Email: Jay.Zwally@nasa.gov
   Phone: 1 301 614-5643 
   Fax: 1 301  614-5644 
   Group: Contact_Address
      Address: NASA/Goddard Space Flight Center
      Address: Laboratory for Hydrospheric Processes
      Address: Laboratory for Hydrospheric Processes
      Address: NASA/Goddard Space Flight Center
      Address: Code 971
      City: Greenbelt
      Province_or_State: MD
      Postal_Code: 20771
      Country: USA
   End_Group
End_Group
Group: Personnel
   Role: Investigator
   First_Name: H. Jay
   Last_Name: Zwally
   Email: Jay.Zwally@nasa.gov
   Phone: 1 301 614-5643 
   Fax: 1 301  614-5644 
   Group: Contact_Address
      Address: NASA/Goddard Space Flight Center
      Address: Laboratory for Hydrospheric Processes
      Address: Laboratory for Hydrospheric Processes
      Address: NASA/Goddard Space Flight Center
      Address: Code 971
      City: Greenbelt
      Province_or_State: MD
      Postal_Code: 20771
      Country: USA
   End_Group
End_Group
Group: Personnel
   Role: Investigator
   First_Name: Robert
   Last_Name: Schutz
   Group: Contact_Address
      Address: University of Texas at Austin
      Address: Center for Space Research
      Address: GLAS Science Team Lead
      Address: University of Texas at Austin
      Address: Center for Space Research
      City: Austin
      Province_or_State: TX
      Postal_Code: 78712-1085
      Country: USA
   End_Group
End_Group
Group: Personnel
   Role: Investigator
   First_Name: John
   Last_Name: Dimarzio
   Email: john.dimarzio@gsfc.nasa.gov
   Phone: 1 301 614-5893 
   Group: Contact_Address
      Address: NASA/Goddard Space Flight Center
      Address: SGT, Inc.
      Address: SGT, Inc.
      Address: NASA/Goddard Space Flight Center
      Address: Cryospheric Sciences Branch Code 614.1
      City: Greenbelt
      Province_or_State: MD
      Postal_Code: 20771
      Country: USA
   End_Group
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Glaciers/Ice Sheets
   Variable_Level_1: Glacier Elevation/Ice Sheet Elevation
   Detailed_Variable: Laser Reflectance
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Glaciers/Ice Sheets
   Variable_Level_1: Glacier Topography/Ice Sheet Topography
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Glaciers/Ice Sheets
   Variable_Level_1: Ice Sheets
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Sea Ice
   Variable_Level_1: Reflectance
   Detailed_Variable: Laser Reflectance
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Oceans
   Term: Sea Ice
   Variable_Level_1: Reflectance
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Terrestrial Hydrosphere
   Term: Glaciers/Ice Sheets
   Variable_Level_1: Glacier Elevation/Ice Sheet Elevation
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Terrestrial Hydrosphere
   Term: Glaciers/Ice Sheets
   Variable_Level_1: Glacier Topography/Ice Sheet Topography
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Terrestrial Hydrosphere
   Term: Glaciers/Ice Sheets
   Variable_Level_1: Ice Sheets
End_Group
ISO_Topic_Category: Elevation
Keyword: Atmospheric Delay Correction
Keyword: DAAC
Keyword: Dem
Keyword: EOSDIS
Keyword: GLA12
Keyword: GLAS
Keyword: Ice Roughness
Keyword: ICESat
Keyword: Ice Sheet Elevation
Keyword: ISIPS
Keyword: Laser Footprint
Keyword: Laser Pulse
Keyword: NASA
Keyword: Noise Level
Keyword: NSIDC
Keyword: Off-nadir Pointing Direction
Keyword: Peak Amplitude
Keyword: Range
Keyword: Received Energy
Keyword: Received Pulse Gain
Keyword: Signal Saturation
Keyword: Solar Incidence Angle
Keyword: Transmitted Energy
Keyword: Transmitted Gain
Keyword: Waveform
Keyword: Waveform Kurtosis
Keyword: Waveform Peak
Keyword: Waveform Skewness
Sensor_Name: GLAS > Geoscience Laser Altimeter System
Source_Name: ICESAT > Ice, Cloud and Land Elevation Satellite
Group: Temporal_Coverage
   Start_Date: 2003-02-20
   Stop_Date: 2009-10-11
End_Group
Data_Set_Progress: complete
Group: Spatial_Coverage
   Southernmost_Latitude: -86
   Northernmost_Latitude: 86
   Westernmost_Longitude: -180
   Easternmost_Longitude: 180
End_Group
Group: Location
   Location_Category: GEOGRAPHIC REGION
   Location_Type: GLOBAL
End_Group
Group: Data_Resolution
   Latitude_Resolution: 60 m
   Longitude_Resolution: 60 m
End_Group
Project: ICESAT > Ice, Cloud and Land Elevation Satellite
Group: Quality

   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.

End_Group
Data_Set_Language: English
Originating_Center: NASA/GSFC/EOS/EO
Group: Data_Center
   Data_Center_Name: NASA DAAC > NASA DAAC at the National Snow and Ice Data Center
   Data_Center_URL: http://nsidc.org/daac/index.html
   Group: Personnel
      Role: Data Center Contact
      First_Name: NSIDC
      Last_Name: User Services
      Email: nsidc@nsidc.org
      Phone: 1 303 492-6199 
      Fax: 1 303  492-2468 
      Group: Contact_Address
         Address: National Snow and Ice Data Center
         Address: CIRES, 449 UCB
         Address: University of Colorado
         City: Boulder
         Province_or_State: CO
         Postal_Code: 80309-0449
         Country: USA
      End_Group
   End_Group
End_Group
Group: Data_Center
   Data_Center_Name: NSIDC > National Snow and Ice Data Center
   Data_Center_URL: http://nsidc.org
   Group: Personnel
      Role: Data Center Contact
      First_Name: NSIDC
      Last_Name: User Services
      Email: nsidc@nsidc.org
      Phone: 1 303 492-6199 
      Fax: 1 303  492-2468 
      Group: Contact_Address
         Address: National Snow and Ice Data Center
         Address: CIRES, 449 UCB
         Address: University of Colorado
         City: Boulder
         Province_or_State: CO
         Postal_Code: 80309-0449
         Country: USA
      End_Group
   End_Group
End_Group
Group: Distribution
   Distribution_Media: FTP
   Distribution_Size: 44 MB
   Distribution_Format: HDF
End_Group
Group: Reference

   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.

End_Group
Group: Summary

   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.

End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW PROJECT HOME PAGE
   End_Group
   URL: http://icesat.gsfc.nasa.gov/
   Description: ICESat/GLAS web site at NASA Goddard Space Flight Center
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW PROJECT HOME PAGE
   End_Group
   URL: http://glas.wff.nasa.gov/
   Description: ICESat/GLAS web site at NASA Wallops Flight Facility
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW PROJECT HOME PAGE
   End_Group
   URL: http://www.csr.utexas.edu/glas/
   Description: ICESat/GLAS web site at University of Texas
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/icesat/index.html
   Description: ICESat/GLAS Data at NSIDC
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/dems/index.html
   Description: Polar Ice Sheet DEMs and Elevation Data
End_Group
IDN_Node: USA/NASA
Metadata_Name: CEOS IDN DIF
Metadata_Version: 9.7
DIF_Creation_Date: 2014-10-17
Last_DIF_Revision_Date: 2014-10-17
DIF_Revision_History:  Publishing deferred.