Skip Navigation Links www.nws.noaa.gov 
NOAA logo - Click to go to the NOAA home page National Weather Service   NWS logo - Click to go to the NWS home page
Climate Prediction Center
 
 

 
About Us
   Our Mission
   Who We Are

Contact Us
   CPC Information
   CPC Web Team

 
HOME > Monitoring_and_Data > Oceanic and Atmospheric Data > Reanalysis: Atmospheric Data > wgrib2 questions
 

wgrib2: limitations

    Limitations on 32-bit computer
  1. The maximum grib file is limited to 2GB unless the file is read sequentially.
    i.e., cat grib_file | wgrib2 - (rest of options)
  2. large grib messages and grids will use buffer space and exhaust physical memory.
  3. grib message is limited to 2GB (fixed v2.0.4)
  4. Any buffer greater than 4GB is a problem.
  5. The maximum grib message is limited to 2GB to 4GB (depending on routine)
  6. The maximum number of grid points varies by routine from to 2G/8 to 4G (grib2 standard).
    The amount of addressable memory will be a limitation.
  7. The maximum bit precision of a complex-packed file is 25.
    Limitations on 64-bit computer
  1. The maximum number of grid points varies by routine from to 2G/8 to 4G (grib2 standard).
    Plan to get get it ot 2G very soon (2/2016) and 4G given a suitable testing environment.
  2. -new_grid is limited to 2G grid points by the fortran library.
  3. grib message is limited to 2GB (fixed v2.0.4)
  4. The maximum bit precision of a complex-packed file is 25.
    Supported Unpacking
  1. simple
  2. simple with log preprocessing
  3. complex
  4. jpeg2000
  5. png
  6. ieee
  7. RLE
    Supported Packing
  1. simple
  2. complex
  3. jpeg2000
  4. ieee
    Grid Support Levels: geolocation
  1. nothing
  2. diagnostic inforamtion
  3. latitude/longitude of the grid points are calculated (spherical earth)
  4. latitude/longitude of the grid points are calculated (aspherical earth)
    Grid Support Levels: ipolates (-new_grid)
  1. nothing
  2. can be an input grid for -new_grid
  3. can be an input or output grid for -new_grid
    Grid Support Levels: -small_grib
  1. nothing
  2. can be an input grid for -small_grib
    Grid support:
  • lat-lon: full support
  • Lambert conformal: full support
  • Polar stereographic: full support
  • Mercator: full support
  • Gaussian: all but -small_grib
  • thinned lat-lon grids: only geolocation
  • rotated lat-lon grids: only geolocation
  • space view perspective: only geolocation
  • Albers equal area: only geolocation
  • Lambert Azimuthal equal area: only geolocation
  • staggering all above except for Gaussian: only geolocation
  • irregular grid: only geolocation

NOAA/ National Weather Service
National Centers for Environmental Prediction
Climate Prediction Center
5830 University Research Court
College Park, Maryland 20740
Climate Prediction Center Web Team
Page last modified: Feb 3, 2016
Disclaimer Privacy Policy