Perpetual years

Running perpetual years

Perpetual years: Running the same year over and over again.

Pick the year you wanto to run. The beginning of this year also has to be the start year ('CLIMAT_startdate') of your simulation.
Just the year in the experiment name will still advance.

Set run to perpetual years

To run perpetual years you have to set in your 'gemclim_settings.nml', namelist 'gement' the parameter 'E_schm_perpetual' to the year you want to run over and over again. For example:

    E_schm_perpetual = 1981 ,

Take care of leap years

Unless you are running a leap year set:

    Leap_years_L    = .false.  ( in 'gemclim_settings.nml', namelist 'physics_cfgs' )

    CLIMAT_leap_year=NO;     ( in 'configexp.dot.cfg' )

Lateral boundary conditions

When running LAM make sure that the nest_info-archive for December also contains data for January 1st of the same year.

SST & sea ice

In the file 'configexp.dot.cfg' set 'CLIMAT_anclim' to an empty file.
(The scripts need a file to link to but the model must not find any usable data in it)

Set 'UM_EXEC_climato' to a file which contains the climatology (for each month) for 'TM' and 'LG' you want.
Make sure that 'IP2' contains the correct month.
Keep the other fields which were in the 'clim_gemdm320_1080x540'.

Green house gases

You will have to keep the green house gases constant.

Therefore set in your 'configexp.dot.cfg':

    CLIMAT_update_ghg=0;

And set 'CLIMAT_ghg_list' to a file which contains, apart from the 6 header lines (important!!!), only a row for the year you want to run. For example the file content for 1981 should look like this:

Global-Mean Greenhouse Gas Mixing Ratios
(http://www.giss.nasa.gov/data/simodel/ghgases)
---------------------------------------------------------------
       CO2    N2O    CH4   CFC-11 CFC-12 others
Year   ppm    ppm    ppm     ppb    ppb    ppb
-------------------------------------------------
1981  340.4  .3022  1.567   .174   .319   .137