Go to the bottom of this page. See the search engine and sub-section links.
Go to next page Go to previous page Go to top of this section Go to top page Go to table of contents

Previous Section Headers

User's Guide to NCAR CCM3.6 Search Page


3. CCM3.6 Internals
    3.5 Output Datasets


3.5.1 History Files

History files contain descriptive information and data values written at specified times during the run. As discussed in Sec. 2.5 , the model automatically writes a "primary" history file, and has the capability of writing up to five "auxiliary" history files if namelist variable INITHIST is set to 'NONE' and up to four otherwise. A "Master Field List" ( Table 2.13 ) contains a list of all the variables that can be output to a history file. Certain fields on the Master Field List appear by default on the primary history file (as indicated in Table 2.13 ). Using the CCMEXP namelist variables PRIMARY , EXCLUDE , and AUXF , the contents of each history file can be customized. Other namelist variables control the time frequency at which each history file is written, along with the type of field averaging (averaged, instantaneous, minimum, maximum, or monthly-averaged), packing density, and number of time samples written to a single history file. The NCAR Mass Store System can be used to archive history files.  History files are written directly in native machine binary format rather than netCDF due to performance considerations and lack of packing support. However, we support a conversion tool (ccm2nc) that converts CCM history files into netCDF. In general any program that reads in a CCM history file, will need to be run on a machine that stores data in the same format as the machine that created the CCM history file. But, ccm2nc is able to recognize and convert IEEE or Cray COS blocked formats from either class of machines. However, currently ccm2nc is not able to recognize or convert byte-swapped data-files.

Sub Sections

    3.5.1.1 History File Format
    3.5.1.2 History File Header Records
    3.5.1.3 Latitude Data Records
    3.5.1.4 History Buffer
    3.5.1.5 History File Code Flow


 Go to the top of this page. See links to previous section headers.
Go to next page Go to previous page Go to top of this section Go to top page Go to table of contents

 Search for keywords in the CCM3.6 Users GuideSearch page

Questions on these pages can be sent to... erik@ucar.edu .


$Name: ccm3_6_6_latest2 $ $Revision: 1.38.2.1 $ $Date: 1999/03/25 21:38:41 $ $Author: erik $