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 BEGIN \\
 \> Initialize \\
 \> \> Define topography, initialize flow field, tracers, etc \\
 \> FOR each time step DO \\
 \> \> {\bf Forward\_Step} \\
 \> \> \> Calculate velocity time derivatives  \\
 \> \> \> Calculate tracer field time derivatives \\
 \> \> \> Step forward state variables \\
 \> \> \> Re-evaluate density field \\
 \> \> {\bf Inversion\_Step} \\
 \> \> \> Solve elliptic problem to ensure non-divergent flow.\\
 \> END FOR \\
 END \\
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