wiki:vamper_main

Instructions to use iLOVECLIM with VAMPER in coupled mode

There is a checklist (attached html file: Evernote_1Aug.html) that user should work through to ensure the coupled experiment is one intended. As of right now, this file should be opened seperately in a browser.
NOTE: everything following is based on version 394


Switches for iLOVECLIM

There is only one switch that adds the VAMPER code to iLOVECLIM and runs it: the VAMPER_KEY, can be zero (no VAMPER), one (synchronous), or two (asynchronous). The asynchronous settings are discussed in the attached .html file 'Evernote_Aug1'.
In lbm/sources/choixcomposantes.h

#define VAMPER_KEY 1

Switches for VAMPER

The VAMPER model may be used as online with iLOVECLIM or as offline. In the current tutorial, we use it as online. The OFFLINE switch thus needs to be set as 0.
In vamper/sources/VAMPER_switches.h

#define OFFLINE 0

The restart file saves the subsurface temperature of each underground node and at each gridcell at the end of the most previous run. These temperatures are therefore used as the beginning conditions in a continued run. To avoid errors, the x_num value should be the same (this is explained in the attached .html file 'Evernote_1Aug'). To use the restart file in a (semi)coupled version, the model reads to / writes from the same .nc file (file name is defined in vamper/sources/parameters.f90). Note this file is overwritten at the end of each run.
Thus, in vamper/sources/VAMPER_switches.h

#define RESTART 2

To employ the snow model, the switch is set to 1.
Thus, in vamper/sources/VAMPER_switches.h

#define SNOW 1

Additional issues

Note: some of these issues are covered when using the checklist supplied in the attached html file

  1. Due to coupling evolution, there is a definition of the number of vertical layers in VAMPER that is called x_num in VAMPER (see vamper/sources/parameters.f90). The same parameter exists in LBM in iLOVECLIM (see in lbm/sources/comland.h), but is not coherently passed through. Thus one needs to check manually if the two values are identical. An error message will occur during the compiling and/or experiment when the x_num values are not identical.
  2. For a semi-coupled version (meaning only iLC gives temps to VAMPER but VAMPER does not give any variable back), the htop=0 (approx. line 504 in lbm/sources/landmodel0.f) SHOULD NOT BE commented out. For full coupling this SHOULD BE commented out.
  3. You must use the same frequency interval value in the VAMPER model ("rec_int" parameter in parameters.f90) as in the iLOVECLIM restart interval value, which is the -r option when starting a run. If not, an error message will occur at the beginning of the experiment letting you know these are not equal.

These are temporary solutions which hopefully change in future (and improved) versions.

Controlling VAMPER parameters

A good place to start to modify the parameters in the VAMPER model is vamper/sources/parameters.f90. A description of the variables will follow for that file.

  • dpth: maximum depth of where temperature is calculated in VAMPER (can be set irrespective of the number of nodes, x_num).
Last modified 7 years ago Last modified on 08/19/14 20:37:38

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