PDS_VERSION_ID      = PDS3                                                    
                                                                              
RECORD_TYPE         = FIXED_LENGTH                                            
RECORD_BYTES        = 80                                                      
OBJECT              = TEXT                                                    
  PUBLICATION_DATE    = 1996-12-01                                            
  NOTE                = "Description of contents of CATALOG                   
                         directory "                                          
END_OBJECT          = TEXT                                                    
END                                                                           
                                                                              
                                                                              
                                                                              
      The CATALOG directory contains reference, personnel, and data set       
PDS catalog objects for this archive volume.  The files follow the            
'streamlined' format adopted by the Planetary Data System (PDS) in late       
1993 and documented in the Planetary Data System Standards Reference          
(Version 3.1, 3 August 1994; JPL D-7669, Part 2).                             
                                                                              
     Each catalog object is in ASCII, with a maximum of 78                    
characters per line.  Each line is delimited with a carriage-                 
return (ASCII 13) line-feed (ASCII 10) pair.                                  
                                                                              
     The templates are:                                                       
                                                                              
COLLECT.CAT                                                                   
     A description of the files forming this data collection.                 
                                                                              
                                                                              
REFS.CAT                                                                      
                                                                              
     A listing of references used elsewhere in the streamlined                
templates and of references that might be generally useful in                 
working with these data.                                                      
                                                                              
                                                                              
PERS.CAT                                                                      
                                                                              
     A listing of key people involved in analyzing the radio                  
occultation data and in producing the archival data set.                      
                                                                              
                                                                              
LAT.CAT                                                                       
LATLON.CAT                                                                    
LATPRS.CAT                                                                    
LATTIME.CAT                                                                   
TIME.CAT                                                                      
TOPOG.CAT                                                                     
     Descriptions of the data sets contained in the archival                  
volume.  These files include information on the primary data                  
types included in this archive.  Brief discussions of the quality             
of the data are included where applicable.  The data sets in the              
archive volume are:                                                           
                                                                              
(1) LAT - This data set contains the time and zonally averaged                
      values calculated by the Ames Mars General Circulation Model            
      for the mean surface and sea level pressures and for several            
      of the vertically integrated heat and angular momentum variables.       
      The data are given as a function of latitude.                           
                                                                              
(2) LATLON - This data set contains the instantaneous values for the          
      surface temperature minimum and maximum, and for the amount of          
      CO2 frost on the ground, calculated by the Ames Mars General            
      Circulation Model.  The data are given as a function of                 
      longitude and latitude.                                                 
                                                                              
(3) LATPRS - This data set contains the time and zonally                      
      averaged values for several first order, heating, eddy, phase           
      and amplitude variables, calculated by the Ames Mars General            
      Circulation Model .  The data are given as a function of                
      latitude and vertical pressure.                                         
                                                                              
(4) LATTIME - This data set contains the zonally averaged values for          
      the surface temperature mean, calculated by the Ames Mars General       
      Circulation Model.  The data are given as a function of latitude        
      and local time.                                                         
                                                                              
(5) TIME - This data set contains the meridionally and zonally                
      averaged values for the CO2 mass condensation rate, calculated          
      by the Ames Mars General Circulation Model.  The data are given         
      as a function of local time.                                            
                                                                              
(6) TOPOG - This data set contains the surface topography used by the Ames    
      GCM, obtained from a combination of relevant ground-based and           
      spacecraft data (commonly known as the "Mars Consortium" data           
      set).  The data were smoothed for compatibility with the model          
      resolution.  The model has 25 latitude bins (7.5 degree resolution)     
      and 40 longitude bins (9.0 degree resolution).