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Dataset Overview | National Centers for Environmental Information (NCEI)

Documentation for the 1996 U.S. Navy's Generalized Digital Environmental Model (GDEM) product database (NCEI Accession 9600094)

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This dataset contains a document describing the US Navy Generalized Digital Environmental Model (GDEM). It does not include the profile data.

The GDEM is a four-dimensional (4-D) steady-state digital model of ocean temperature and salinity. The model consists of gridded sets of coefficients with a grid spacing of 30 arcminutes (') in space and 3, 6, or 12 months in time with the exception of the coefficient describing sea-surface temperature, which is gridded at a 1-month interval. Utilizing these coefficient sets with the appropriate one-dimensional linear or cubic spline interpolation in time, vertical profiles of historical temperature and salinity extending from the surface to the bottom may be computed for a desired time for all locations where the water depth is at least 100 m.

The VGDEM is a 4-D model of ocean temperature variability. A number of accumulations and parameters exists for each grid cell such that statistics on the observations can be derived; statistics based on comparing the observations with GDEM can be computed; and statistics computed for the mixed-layer depth and the in-layer and below-layer gradients. The percent of the observations suggesting half-channel is also available. Variability models will be constructed only in the ocean basins where data density permits. Therefore, models for the South Atlantic, South Pacific, and Arctic Oceans will not be developed at this time.

The original source of data for the construction of these climatological models is the Master Oceanographic Observation Data Set (MOODS), which contains over 4.5-million profiles of temperature/salinity dating back to 1920. This data base is maintained by NAVOCEANO and is continually updated.
  • Cite as: US Naval Oceanographic Office (2003). Documentation for the 1996 U.S. Navy's Generalized Digital Environmental Model (GDEM) product database (NCEI Accession 9600094). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/9600094. Accessed [date].
gov.noaa.nodc:9600094
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Distribution Formats
  • Originator data format
Ordering Instructions Contact NCEI for other distribution options and instructions.
Distributor NOAA National Centers for Environmental Information
+1-301-713-3277
NCEI.Info@noaa.gov
Dataset Point of Contact NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Time Period 1920-01-01 to 1996-06-01
Spatial Bounding Box Coordinates
West:
East:
South:
North:
Spatial Coverage Map
General Documentation
Publication Dates
  • publication: 2003-10-24
Data Presentation Form Digital document - digital representation of a primarily textual item (can contain illustrations also)
Dataset Progress Status Complete - production of the data has been completed
Historical archive - data has been stored in an offline storage facility
Data Update Frequency As needed
Supplemental Information
As of January 2012, data associated with this accession are only available offline on 4mm DAT magnetic tape media. NCEI is currently unable to provide this data.

For global observational ocean in situ profile data, please see the World Ocean Database at https://www.ncei.noaa.gov/products/world-ocean-database
and the WOD Select System https://www.ncei.noaa.gov/access/world-ocean-database-select/dbsearch.html

For ocean climatologies based on the WOD observations, see our gridded World Ocean Atlas (WOA).
Gridded Data sets: https://www.ncei.noaa.gov/data/oceans/woa/WOA18/DATA/
and Figures: https://www.ncei.noaa.gov/access/world-ocean-atlas-2018f/
WOA Homepage: https://www.ncei.noaa.gov/products/world-ocean-atlas

If you need help with WOD or WOA, please write to OCL.Help@noaa.gov.
Purpose This dataset is available to the public for a wide variety of uses including scientific research and analysis.
Use Limitations
  • accessLevel: Public
  • Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
Dataset Citation
  • Cite as: US Naval Oceanographic Office (2003). Documentation for the 1996 U.S. Navy's Generalized Digital Environmental Model (GDEM) product database (NCEI Accession 9600094). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/9600094. Accessed [date].
Cited Authors
Contributors
Resource Providers
Publishers
Use Constraints
  • Cite as: US Naval Oceanographic Office (2003). Documentation for the 1996 U.S. Navy's Generalized Digital Environmental Model (GDEM) product database (NCEI Accession 9600094). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/9600094. Accessed [date].
Access Constraints
  • Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
Fees
  • In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media.
Lineage information for: dataset
Processing Steps
  • 2003-10-24T17:46:40Z - NCEI Accession 9600094 v1.1 was published.
Output Datasets
Lineage information for: repository
Processing Steps
  • 2015-04-22T00:00:00 - NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015.
Last Modified: 2024-01-07T16:11:07Z
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