surface_flux_mod is configured via the surface_flux_nml namelist in the input.nml file. The following table are the available namelist variables.

Variable Name	Type	Default Value	Description
no_neg_q	logical	.FALSE.	If q_atm_in (specific humidity) is negative (because of numerical truncation), then override with 0.
use_virtual_temp	logical	.TRUE.	If true, use virtual potential temp to calculate the stability of the surface layer. if false, use potential temp.
alt_gustiness	logical	.FALSE.	An alternative formulation for gustiness calculation. A minimum bound on the wind speed used influx calculations, with the bound equal to gust_const.
old_dtaudv	logical	.FALSE.	The derivative of surface wind stress w.r.t. the zonal wind and meridional wind are approximated by the same tendency.
use_mixing_ratio	logical	.FALSE.	An option to provide capability to run the Manabe Climate form of the surface flux (coded for legacy purposes).
gust_const	real	1.0	Constant for alternative gustiness calculation.
gust_min	real	0.0	Minimum gustiness used when alt_gustiness = false.
ncar_ocean_flux	logical	.FALSE.	Use NCAR climate model turbulent flux calculation described by Large and Yeager, NCAR Technical Document, 2004.
ncar_ocean_flux_orig	logical	.FALSE.	Use NCAR climate model turbulent flux calculation described by Large and Yeager, NCAR Technical Document, 2004, using the original GFDL implementation, which contains a bug in the specification of the exchange coefficient for the sensible heat. This option is available for legacy purposes, and is not recommended for new experiments.
raoult_sat_vap	logical	.FALSE.	Reduce saturation vapor pressures to account for seawater salinity.
do_simple	logical	.FALSE.	</table