The AdamsBashforth extrapolation of explicit tendencies fits neatly
into the pressure method algorithm when all state variables are
colocated in time. Fig. 2.5 illustrates
the location of variables in time and the evolution of the algorithm
with time. The algorithm can be represented by the sequential solution
of the follow equations:
Fig. 2.5 illustrates the location of variables in time and evolution of the algorithm with time. The AdamsBashforth extrapolation of the tracer tendencies is illustrated by the dashed arrow, the prediction at is indicated by the solid arc. Inversion of the implicit terms, , then yields the new tracer fields at . All these operations are carried out in subroutine THERMODYNAMICS an subsidiaries, which correspond to equations 2.29 to 2.32. Similarly illustrated is the AdamsBashforth extrapolation of accelerations, stepping forward and solving of implicit viscosity and surface pressure gradient terms, corresponding to equations 2.34 to 2.40. These operations are carried out in subroutines DYNAMCIS, SOLVE_FOR_PRESSURE and MOMENTUM_CORRECTION_STEP. This, then, represents an entire algorithm for stepping forward the model one timestep. The corresponding calling tree is given in 2.6.
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