GEMCLIM input files
GEMCLIM reads several input files.
Apart from the config files
'configexp.dot.cfg',
'gemclim_settings.nml',
and 'outcfg.out'
there are:
Geophysical fields
The geophysical fields should always match your
grid!
Although the model can always interpolate, it is highly recommended to
create the geophysical fields from a high resolution database using one the
following tools: 'Genesis', 'Gengeo' or 'GenPhysX'.
Unfortunately none of them are installed outside of CMC/RPN. So if you need
geophysical fields for a certain grid and do not have access to the
machines from Environment Canada in Dorval, send the grid
specifications (namelist 'grid' in your 'gemclim_settings.nml') to
Katja.Winger@ec.gc.ca.
The fields contained in this file are fields of quantities including:
For more information on the geophysical fields in this file, please check here (courtesy of Ayrton Zadra).
Analysis or
initial condition file
The analysis or initial condition file contains all fields needed to
initialize soil and atmospheric variables in your run. The fields in this file do
not need to match your grid (though they need to cover the
whole area). But they need to match your start date.
Check the following links to learn more about the fields of an analysis file
and how to create an
analysis file.
SST and Sea Ice
boundary conditions
The SST and Sea Ice boundary conditions we provide are the 1° monthly BC's
from AMIP2.
These data are derived from the observational data set.
The primary difference between the boundary condition data set and the
observational data set is that adjustments have been made to insure
that when daily values are linearly interpolated between the
monthly
values contained in the data set (i.e., when used as boundary
conditions in GEMCLIM), the monthly average of the observations is
preserved.
Although this file is an RPN standard file, it is a little special:
The field descriptor 'ip2' does
contain the month and the field descriptor 'ip3' the year for which a
record is valid.
*** Never modify this file with 'r.diag' *** as 'r.diag' changes the values of the 'ip'-fields.
Climatology file
This file contains the monthly climatologies for fields like:
- SST, surface and deep soil temperature
- Sea ice thickness and fraction
- Snow depth
- Surface albedo
In general, the model and entry first have a look into one of the three
files above. But if a field cannot be found in any of them, model/entry looks for
it (for certain fields only) in the climatology file.
Usually we only read the surface albedo to initialize the run and the
deep soil temperature on the 15th of each month.
Although this file is an RPN standard file, it is a little special: The field descriptor 'ip2' contains the month.
And again, *** Never modify this file with 'r.diag' *** as 'r.diag' changes the values of the 'ip'-fields.
Ozone file
The default ozone climatology file read by GEMCLIM is the ozone
climatology proposed in the AMIP2 experimental protocol. It contains
data on 61 latitudes and 59 levels.
Note: If
another ozone file is to be used, the physics routine 'litozon2.ftn'
and the 'ozopnt.cdk' comdeck need to be changed accordingly!
Author: Katja Winger
Last update: June 2008