Advanced Topics Mars PEM

Choices of parameters (run_PEM.def)

Parameters of the PEM run can be specified in run_PEM.def. This file is included at the end of the run.def. run_PEM.def file can be found in LMDZ.MARS/deftank/pem. For now, these are the possible parameters:

General parameters for the run

• evol_orbit_pem: [Boolean] Do you want to follow an orbital forcing predefined (read in ob_ex_lsp.asc for example)? (default=false)
  • If evol_orbit_pem is set to true, year_bp_ini needs to be specified
  • year_bp_ini: [Integer] Number of (Earth) year before present to start the pem run if evol_orbit_pem=.true. , default=0
  • var_obl: [Boolean] Do you want to vary the obliquity when following ob_ex_lsp.asc? Default =.true.
  • var_ex: [Boolean] Do you want to vary the excenticity when following ob_ex_lsp.asc? Default =.true.
  • var_lsp: [Boolean] Do you want to vary the ls perihelie when following ob_ex_lsp.asc? Default =.true.
• Max_iter_pem: [Integer] Maximal number of iteration if none of the stopping criterion is reached and if evol_orbit_pem=.false., default=99999999
• dt_pem: [Integer] Time step of the PEM in year, default=1
• ice_criterion: [Real] Acceptance rate of sublimating ice surface change, default=0.2
• ps_criterion: [Real] Acceptance rate of pressure surface change, default=0.15

Subsurface

• soil_pem: [Boolean]. Do you want to run with subsurface physical processes in the PEM? default=.true.
• adsorption_pem: [Boolean]. Do you want to run with adsoprtion in the PEM? default=.true.
• reg_thprop_dependp: [Boolean]. Do you want to modify the soil thermal properties with the pressure ? default=.false.

Layering:

• fluxgeo: [Real]. Value of the geothermal flux? default= 0.
• depth_breccia: [Real]. Depth at which the breccia layer begins? default= 50 m
• depth_bedrock: [Real]. Depth at which the bedrock layer begins? default= 1000 m

Reservoirs

• water_reservoir_nom: [Real]. Value of the available water in the subsurface. default =1e4 in kg/m^2