19.1.1 GASBC

Getting for the atmosphere model defined on the atmosphere grid is the purpose of subroutine gasbc^19.13 which is an acronym for get atmosphere surface boundary conditions. All of the are two dimensional fields defined in longitude and latitude at model grid points. In the ocean, all quantities which are to be used as for the atmosphere are defined on the grid^19.14 in array where subscript m refers to the ordering described in Section 19.3. Typically, only SST is needed but it may be desirable to let the atmosphere sense that the ocean surface is moving in which case the horizontal velocity components might also be used (Pacanowski 1987). In any event, these quantities are accumulated in within MOM and averaged at the end of each time segment. Basically what needs to be done in gasbc is to interpolate the time averaged fields to which is an array of the same except defined on the atmosphere boundary condition grid^19.15 A $_{i^\prime,j^\prime}$. One of the duties of setatm is to define A $_{i^\prime,j^\prime}$ as the atmospheric boundary condition grid which includes extra boundary points along the borders to facilitate these interpolations.