The pressure-averaging technique was explained in a previous section. Because it increases the timestep, it should always be enabled. The option to turn it off is provided only to permit comparisons with and without pressure-averaging or between POP and other codes that do not incorporate this technique.

The pressure gradient term includes a density factor which is assumed to be a constant reference density in Boussinesq models. The depth-dependent pressure effects on this density can be corrected for using simple depth-dependent factors.

Table: Pressure averaging namelist
&pressure_grad_nml LANL
default		 CESM1
default		 Valid
values		 Averaging of horizontal pressure gradient
lpressure_avg.true..true..true., .false.use pressure averaging to increase time step
lbouss_correct.true..false..true., .false.applies depth-dependent factor to correct for assumed constant density
/