MEPRA avalanche hazard diagnostic¶

The output variables of MEPRA are listed below.

The MEPRA output depends on the selected output timestep (configuration in SURFEX namelist). The operational value used at Météo-France is 3h.

stress/strength stability index :

• NAT_RAT : MEPRA strength/stress ration without skier
• ACC_RAT : MERPA strength/stress ratio with skier

Expert risks :

• NAT_LEV : MEPRA natural risk (range 0-5, 6 means undefined)
• ACC_LEV : MERPA accidental risk (range 0-3, 4 means undefined)
• AVA_TYP : MEPRA avalanche type (0: new snow dry, 1:new snow wet, 3: new snow mix, 4: surface melt, 5:depth melt, 6:undefined)

Depth of identified avalanche problems:

• DEP_HIG : MEPRA Depth of high level avalanche problem
• DEP_MOD : MEPRA Depth of the second avalanche problem

Mechanical properties :

• SNOWRAM : RAM Resistance (daN)
• SNOWSHEAR : Shear Resistance (kPa)