Section 19.2 describes three simple atmospheres requiring very little computation. In all cases, the atmosphere is sensitive to SST but not sea surface salinity. Since fresh water flux into the ocean is not known very accurately, it is reasonable to damp sea surface salinity back to climatological values on some Newtonian time scale for a surface boundary condition. As mentioned in Section 19.3, restoring SST and sea surface salinity to data can be done by enabling option restorst. Note that damping time scale may by set differently for each tracer. However, instead of restoring SST, the next simplest atmosphere in the hierarchy may be thought of as being parameterized with bulk formulae as given by the idealized version in Philander/Pacanowski (1986) or the more complete version in Rosati/Miyakoda (1988).
Although these bulk parameterizations are not included in MOM as of this writing, they are easy to implement. The largest uncertainties are due to clouds. Caution must be used with this type of atmosphere since the global integral of heatflux into the ocean averaged over one seasonal cycle may be non-zero which may lead to a drift in the ocean heat content with time.