Data Set Overview
    =================
      The Ames Mars General Circulation Model is a three dimensional
      model based on the primitive equations of meteorology.  It
      includes the radiative effects of dust and carbon dioxide as
      well as other features such as large-scale topography (see
      [POLLACKETAL1990]; [BARNESETAL1993]; and [HABERLEETAL1993]).
 
      The model has 25 latitude bins (7.5 degree resolution), 40
      longitude bins (9.0 degree resolution) and 13 vertical layers.
      The spacing between each layer varies.  The following array
      defines the layer spacing from the tropopause to the surface in
      mbars:
 
        0.005779, 0.009511, 0.01568, 0.02585, 0.04263, 0.07025,
        0.1159, 0.1544, 0.1586, 0.1364, 0.1223, 0.09270, 0.05000.
 
      The model spins up from a resting isothermal state with the
      global temperature equal to 200K.  The spin up starts with hour
      equal to 0.  The model saves data every 1.5 hours for a total
      of 16 hour bins per day.
 
      Some other initial conditions that are set when the model spins
      up:
 
      INITIAL SURFACE PRESSURE      : 7.60 mbars
      TROPOPAUSE PRESSURE           : 0.06699 mbars
      DUST OPTICAL DEPTH            : 0.3 (for periods where Ls < 200)
      DUST OPTICAL DEPTH            : 1.0 (for periods where Ls > 200)
      ICE CLOUD OPTICAL DEPTH       : 0.00
      TIME STEP                     : 9.25 minutes
      RICHARDSON NUMBER TIME SCALE  : 200000000. seconds
      SCALE HEIGHT FOR DUST PROFILE : 0.03000
      TIME CONSTANT FOR RAYLEIGH
        FRICTION                    : 2.0000 days
 
      This data set is composed of 20 to 30 day averages of the data
      resulting from model runs simulating martian conditions for
      four Ls periods during 1977 (Ls 10-24, 94-103, 202-220, and
      267-286).
 
        Native start time  =  10.15 AREOCENTRIC LON, EARTH YEAR 1977
        Native stop time   = 286.09 AREOCENTRIC LON, EARTH YEAR 1977
 
      The latitude data set contains the time and zonally averaged
      values for the mean surface and sea level pressures and for
      several of the heat and angular momentum variables.  The data
      are given as a function of latitude.  The calculations are done
      in the pi coordinate system; pi coordinates are located at the
      intersection points of a set of evenly spaced latitude circles
      and a set of evenly spaced longitude circles.
 
      The data set is in the following configuration (listed as field
      followed by description):
 
      LATITUDE
         Latitude, degrees
 
      SURF_PRES
         Mean surface pressure, mbars
 
      SEA_LEV_PRES
       Mean sea level pressure, mbars
 
      MASS_FLOW
         Mass flow, m/s
 
 
      CO2 mass budget parameters
      --------------------------
      CO2_ATM
         CO2 atmospheric condensation, kg/m**2/sec
 
      CO2_SUR
         CO2 surface condensation, kg/m**2/sec
 
      CO2_TOT
         Total CO2 condensation, kg/m**2/sec
 
 
      Dynamical heat budget parameters
      --------------------------------
      HEAT_OC
         Heating due to overturning cells, watt/m**2
 
      HEAT_CF
         Heating due to condensation flow, watt/m**2
 
      HEAT_SE
         Heating due to stationary eddies, watt/m**2
 
      HEAT_TE
         Heating due to transient eddies, watt/m**2
 
 
      Total heat budget parameters
      ----------------------------
      HEAT_NET
         Net Radiation, watt/m**2
 
      HEAT_LH
         Latent heat, watt/m**2
 
      HEAT_TR
         Heating due to transport, watt/m**2
 
      HEAT_FD
         Heating due to frictional dissipation, watt/m**2
 
      HEAT_SH
         Sensible heat, watt/m**2
 
      HEAT_SUM
         Total heating, watt/m**2
 
 
      Dynamical angular momentum budget parameters
      --------------------------------------------
      MOMENT_OC
         Angular momentum due to overturning cells, kg/sec**2
 
      MOMENT_CF
         Angular momentum due to mass flow, kg/sec**2
 
      MOMENT_SE
         Angular momentum due to stationary eddies, kg/sec**2
 
      MOMENT_TE
         Angular momentum due to transient eddies, kg/sec**2
 
 
      Total angular momentum budget parameters
      ----------------------------------------
      MOMENT_MT
         Momentum due to mountain torque, kg/sec**2
 
      MOMENT_GF
         Momentum due to ground frictional torque, kg/sec**2
 
      MOMENT_THT
         Angular momentum due to total horizontal transport, kg/sec**2
 
      MOMENT_RF
         Angular momentum due to Rayleigh friction torque, kg/sec**2
 
      MOMENT_CT
         Angular momentum due to condensation torque, kg/sec**2
 
      MOMENT_SUM
         Torque sum, kg/sec**2

Confidence Level Overview
    =========================
      The Ames Mars General Circulation Model is a three dimensional
      computer model based upon the primitive equations of
      meteorology.  It includes the radiative effects of dust and
      carbon dioxide as well as other features such as large-scale
      topography.  Model results are dependent upon the selected
      initial conditions and spatial and temporal resolution of the
      model, and may not fully incorporate the effects of some
      physical processes represented by paramaterizations made by the
      model.