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jahn |
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Package longstep |
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This package allows the passive tracer time step to be longer than that for |
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dynamical fields: the ptracers are updated only every LS_nIter time step. |
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Dynamical fields are averaged over LS_nIter time steps and are available as |
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fields LS_* (declared in LONGSTEP.h): |
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original fld. averaged fld. |
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------------------------------ |
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UVEL LS_uVel |
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VVEL LS_vVel |
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WVEL LS_wVel |
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THETA LS_theta |
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SALT LS_salt |
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IVDConvCount LS_IVDConvCount |
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Qsw LS_Qsw |
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Kwx LS_Kwx |
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Kwy LS_Kwy |
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Kwz LS_Kwz |
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KPPdiffKzS LS_KPPdiffKzS |
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KPPghat LS_KPPghat |
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The T and S time step remains the same as that for u,v,... |
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Packages that use ptracers (like DIC) need to be adapted: |
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1. replace dtTracerLev by PTRACERS_dTLev |
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2. replace THETA, SALT, etc. by their longstep averages from the table above. |
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This should be made between #ifdef ALLOW_LONGSTEP ... #endif. |
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(You need to #include "LONGSTEP.h") |
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The package is activated by including "longstep" in packages.conf. There is |
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no "use_LONGSTEP", the package is always on when compiled. |
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The run-time parameters are set in data.longstep. The default is: |
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&LONGSTEP_PARM01 |
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LS_nIter=1, |
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LS_afterTS=.FALSE., |
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LS_staggerTimeStep=.FALSE., |
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& |
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LS_nIter :: number of dynamical time steps per ptracer time step. |
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LS_afterTS :: sample dynamical fields after updating T and S (after thermodynamics), |
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i.e. at the same time as gchem_forcing_sep is called. |
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This reproduces runs without longstep when LS_nIter == 1 |
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LS_staggerTimeStep :: same as LS_afterTS for staggerTimeStep == .TRUE. |
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Default is to sample dynamical fields at the beginning of the time step. This |
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reproduces results from offline runs (with straight time averages used for the |
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dynamical fields). |