6.2.3. Sea-ice schemes

From Version 8, Surfex handles sea-ice either :

Report on implementing sea-ice schemes and Gelato in Surfex
  • by using sea-ice cover forcing data from PREP file
  • or by activating a sea-ice prognostic scheme.

This allows to compute surface fluxes which are much more realistic than when using only Sea Surface Temperature (SST). A report on this development is available in V8 documentation

A sea-ice scheme is activated at the PREP stage using parameter CSEAICE_SCHEME of NAM_PREP_SEAFLUX (see 5.3.1. Namelist NAM_PREP_SEAFLUX). It also involves some settings in the relevant namelist : 6.2.5. Namelist NAM_SEAICEn. A sea-ice scheme must be provided with Sea Surface Temperature (SST), and Salinity (SSS) fields, in a way described at 6.2.1. Namelist NAM_SEAFLUXn

When a sea-ice scheme is not activated, sea-ice cover is anyway handled if CINTERPOL_SIC /= NONE in NAM_SEAICE , then :

  • sea-ice cover forcing data must be provided in the PREP file
  • sea surface temperature is used as sea-ice temperature on locations where sea-ice cover is not zero
  • a constant sea-ice albedo is used (see XCST_ICE_ALB in 6.2.5. Namelist NAM_SEAICEn)

In both cases :

The Gelato sea-ice prognostic scheme is the only sea-ice scheme yet managed with NAM_SEAICE. It is described at 6.2.4. Gelato sea-ice scheme