'restoring'
a simple restoring of the top layer potential temperature in the model to a data value, dT/dt = (Tdata - Tmodel) / τ, where τ is a constant time scale. Tdata represents a space- and possibly time-dependent array of values of sea-surface temperature (SST) and is the only necessary forcing field. If this option is chosen, then a value for the space- and time-independent restoring time-scale variable shf_restore_tau (in days) also needs to be specified.
'Barnier-restoring':
use the ECMWF heat flux analysis of [2] arranged in restoring form. Necessary forcing fields consist of (in order) an effective SST, spatially varying restoring time scale, sea ice mask, and net downward short-wave radiation. If this option is chosen, then it is also necessary to specify the namelist variable jerlov_water_type to calculate the depth of short-wave penetration.
'bulk-NCEP':
calculate fluxes based on atmospheric state variables and radiation similar to a fully-coupled model (and using bulk flux formulations extracted from the NCAR flux coupler). Necessary forcing fields consist of (in order) SST, air temperature, air humidity, downward short-wave radiation, cloud fraction, and wind speed. If this option is chosen, then it is also necessary to specify the namelist variable jerlov_water_type to calculate the depth of short-wave penetration. This option also expects the name of a file used to define different regions of the ocean (including marginal seas) specified by the namelist variable region_mask_filename in the grid namelist.