Next, the user must decide how to temporally interpolate the forcing data to the appropriate point in time for the model to use. If the data type of the forcing is either 'none', 'analytic', or 'annual', then the interpolation options are disregarded since the forcing is invariant in time. The type of interpolation is specified by the value of *_interp_type and the options are (envelope,please):
'nearest': use the forcing from the time that is closest to the current model time
'linear':
use a linear interpolation to the current model
time using the two nearest forcing times
'4point': use a 3rd order polynomial fit using the 4 nearest
forcing times and evaluate it at the current model time
How often interpolation is done is specified using the namelist
variables *_interp_freq and the options are:
'never': never perform any temporal interpolation
'n-hour': perform temporal interpolation every 'n' hours.
If this is chosen, the user must also specify a
value for *_interp_inc which is the
increment (in hours) between interpolation
calculations. Note that it is assumed that this
value is less than or equal to the data increment.
'every-timestep': perform temporal interpolation every timestep