The reader will note that all numerical indices are exposed within expressions so as to match exactly with those used in the Fortran code. This extra bit of detail is insisted upon as another way of insuring that complex formulations are correct.
Once are available for the ocean as described in Chapter 19, the ocean equations are integrated for one time step with each call to subroutine mom22.1. As indicated schematically in Figure 19.2 and described further in Section 19.1, mom may need to be called repeatedly until integration has been carried out for one time segment. For a flowchart indicating the calling sequence within mom for one time step, refer to Figure 22.1. The process starts by incrementing the ocean time step counter itt by one
| itt = itt + 1 | (22.1) |
and calling module tmngr22.2 which increments ocean time by the number of seconds in one time step. Refer to Section 14.4.4 for choosing a time step length. Module tmngr additionally calculates a time and date as described in Section 15.1.9 and determines which events are to be activated on the current time step and which are not. Each event has an associated logical switch which is kept in file switch.h. An event might be something like writing a particular diagnostic for analysis, or doing a mixing time step, etc. After determining all logical switches, a call is made to the diagnostic initialization subroutine diagi which performs initializations for various diagnostics when required22.3.