JISAO data


Elevation data in netCDF

Global domain.
1-degree latitude-longitude resolution elevations, light shading for elevations < -5000m, and increasingly darker shades for elevations > 0 and 1500m. This choice of shading captures the deeper parts of the world oceans, the Himalayas, Rockies, and the Andies, and shows that much of Antarctica is a high plateau. The elevation data set used for this figure is linked here (in netCDF).

The best WWW page of elevation data sets that I have found is that of the National Center for Atmospheric Research (NCAR). Most of the datasets that I provide were constructed from a 5-minute resolution data set at NCAR called "TerrainBase" (TBASE). There is now a 2-minute version of TerrainBase that you can download.

  • At JISAO, all of these files reside at /home/disk/margaret/data/elevation/
  • 5-minute latitude-longitude resolution elevation for just the Americas TBASE
  • 0.25-degree latitude-longitude resolution elevation (calculated from TBASE)
  • 0.5-degree latitude-longitude resolution elevation (calculated from TBASE)
  • 1-degree latitude-longitude resolution elevation (Rand Corporation / Scripps Institution of Oceanography)
  • 2-degree latitude-longitude resolution elevation (calculated from TBASE)
  • fractional land (0-1) at 0.25-degree latitude-longitude resolution.
  • fractional land (0-1) at 0.5-degree latitude-longitude resolution.
  • fractional land (0-1) at 1-degree latitude-longitude resolution.
  • fractional land (0-1) at 2-degree latitude-longitude resolution.
  • fractional land (0-1) at 2.5-degree latitude-longitude resolution.
  • fractional land (0-1) at 5-degree latitude-longitude resolution.
    
    

    
    
    How to shade continents in GrADS.

    GrADS is free software that employs a command-line interface (you type commands in). The following describes how to draw the figure at the top of this WWW page.

    grads  * To start the session
    
    * Define some gray shades
    set rgb 16 153 153 153
    set rgb 18 205 205 205
    set rgb 19 230 230 230
    
    sdfopen elev.1-deg.nc 
    
    set background 0    
    set mpdraw off      
    set grid off
    set grads off
    
    set dfile 1
    set gxout shaded    
    set clevs -1500 0 1500
    set ccols 19 0 18 16
    d data              
    
    
    

    July 2008
    Todd Mitchell (mitchell@atmos.washington.edu)
    JISAO data