General information

SPS stands for Surface Prediction System. It was developed by ECCC. It executes only the surface routines from GEM, driving it with the following external driving data:

• Surface pressure (P0)
• Surface temperature (TT) (at 2 m but preferably on the lowest predictive model level)
• Surface humidity (specific (HU) or relative (HR))  (at 2 m but preferably on the lowest predictive model level)
  
• Surface u- and v-winds (UU and VV) (at 10 m but preferably on the lowest predictive model level)
• Surface downward shortwave radiation (N4)
• Surface downward longwave radiation (AD)
  

Like GEM it also need the following lower boundary conditions:

• Sea surface temperature in Kelvin (TM)
• Sea ice fraction (LG)

Other than GEM, SPS does not offer the possibility to write and read restart files. Therefore, at the end of each job all fields needed to start another simulation need to get outputted. The next job will then use the output of the previous job as initial conditions. See below under 'outcfg.out' which fields these are.

SPS 6.1.1 uses the same physics version as GEM 5.1.1.

I suggest you create yourself a directory under your home for your source code, scripts and config files, for example:

Scripts

The name of the scripts directory:
    ~/SPS/v_6.1.1/Scripts
is mandatory!

In the above directory you need to have the following scripts:

You can copy the scripts from the following directory:

Executable

The following is a recipe to create your own executable:

a) Create directory for executable

To create an executable first create yourself a directory under your home for the source code; preferably under ~/SPS/v_6.1.1/Abs and change into it, for example:

b) Get the basename of abs-directory

Get the basename (last part of your directory path) of your abs-directory for later use:

'base_dir' should now be set to 'My_Abs'. You can verify it with:

            echo $base_dir

c) Clone the SPS Git repository you want to start from, for example:

Then change into 'sps' directory that came with the clone:

d) Create working directories

So the object files, libraries and executables will not be under your home, create links for the directories 'build' and 'work'. Pick a place under which you want to keep these file under your data space, something like:

Create the directories and the links (using ${base_dir} from above) :

e) Acquire a compiler

Only needed once per window/terminal. Same as for GEM 5.1.1.

The alias 'sps611' should work as well. But better only use it once per window because each time it is used it will add a directory to your $PATH.

f) Set the variable 'abs_dir'

Set the variable 'abs_dir' to the name of your executable directory, including the 'sps' directory (needed under h))

g) Change into 'build' directory:

h) Create make files and dependencies

Only need once at the beginning and whenever you add any new routines or add include files or module "use" lines to an existing routine.

i) Compile and create executable

You can also use n cores in parallel by adding the '-jn', for example to use 4 cores:

     make -j4 mainspsdm

Config files

You need the following config files:

configexp.cfg

Example file with variable explanations:

outcfg.out

SPS does not have the possibility to write and continue from restart files. Therefore, at the end of each job all fields needed to start another simulation need to get outputted. The next job will then use the output of the previous job as initial conditions. To make the output of fields at the end of a job easier, steps=1 and steps=2 are now hard coded to:

ISBA

The following is a list of mandatory initial condition fields for ISBA:

    SD : VD=snow depth
    DN : VD=relative snow density
    I0 : VD=surface and soil temperatures
    I1 : VD=soil volumetric water contents
    I2 : VD=soil volumetric ice contents
    I3 : VD=water retained on the vegetation
    I4 : VD=water in the snow pack
    I5 : VD=snow mass
    I6 : VD=albedo of snow
    I7 : VD=sea ice temperature
    I8 : VD=sea ice thickness
    I9 : VD=glacier temperature

FLake

The following is a list of mandatory initial condition fields for FLake:

CLASS

When running CLASS, in addition to the ISBA fields above one also needs to output the following fields:

sps.cfg

Driving with fields on staggered lowest predictive model levels

1) Lvl_typ_S = 'HS'     (HS= Hybride Staggered..     HU=  Hybride Uniforme (toutes les variables sur le meme niveau)

2) Lvl_list = MOMENTUM LEVEL ONLY                -   SPS will deduce the thermo level by itself

3) ip1a=-1
     ip1at=-1

For (3) , By using =-1, you let SPS figure out the ip1 using the standard encoding.  (*Note that I don’t know what the “standard” is, I’m under the impression the ip1 encoding has changed with various GEM versions but perhaps it remained constant for HS levels).

If the ip1 encoding is not standard,  you can override the ip1s using these 2 keys. In all cases, standard or not, you can choose to specify these.

The actual values for the lowest prognostic level + ip1s will depend on the forcing model configuration. It will vary from one GEM system to another.

Example:

Driving with fields on diagnostic levels

Example:

Launching SPS simulation

1) First you need to set the SPS environment

You can do this with the alias:

But better use it only once per window(!) because each time this alias is executed it will add a directory to your $PATH.

2) Go into the directory containing your config files:

3) Launch the simulation

To launch the simulation you just have to execute the command:

4) Check progress

You can check the progress of an SPS simulation the same way as for GEM by executing 'u.tail' on the model listing under ~/listings/${TRUE_HOST}:

Note that model listings will not - yet - get archived at the and of a job as done in GEM!

Restart / Continue a simulation

First, make sure all previous model output has been moved to the archive directory. To do that, go into your config file directory and execute the post pocessing script with:

Then resubmit the simulation from the last initial condition output you have with:

Where "YYYY MM DD hh" is the start date and hour of the job you want to start within the whole simulation, which is probably the date of your last initial condition output.