| 1 |
C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/GAD_OPTIONS.h,v 1.13 2008/05/09 21:43:16 jmc Exp $ |
| 2 |
C $Name: $ |
| 3 |
|
| 4 |
CBOP |
| 5 |
C !ROUTINE: GAD_OPTIONS.h |
| 6 |
|
| 7 |
C !INTERFACE: |
| 8 |
C #include "GAD_OPTIONS.h" |
| 9 |
|
| 10 |
C !DESCRIPTION: |
| 11 |
C Contains CPP macros/flags for controlling optional features of package. |
| 12 |
CEOP |
| 13 |
|
| 14 |
C CPP options file for GAD (Generic Advection Diffusion) package |
| 15 |
C |
| 16 |
C Use this file for selecting options within the GAD package |
| 17 |
|
| 18 |
#ifndef GAD_OPTIONS_H |
| 19 |
#define GAD_OPTIONS_H |
| 20 |
#include "PACKAGES_CONFIG.h" |
| 21 |
#ifdef ALLOW_GENERIC_ADVDIFF |
| 22 |
|
| 23 |
#include "CPP_OPTIONS.h" |
| 24 |
|
| 25 |
C This flag selects the form of COSINE(lat) scaling of bi-harmonic term. |
| 26 |
C *only for use on a lat-lon grid* |
| 27 |
C Setting this flag here only affects the bi-harmonic tracer terms; to |
| 28 |
C use COSINEMETH_III in the momentum equations set it CPP_OPTIONS.h |
| 29 |
#define COSINEMETH_III |
| 30 |
|
| 31 |
C This selects isotropic scaling of harmonic and bi-harmonic term when |
| 32 |
C using the COSINE(lat) scaling. |
| 33 |
C Setting this flag here only affects the tracer diffusion terms; to |
| 34 |
C use ISOTROPIC_COS_SCALING of the horizontal viscosity terms in the |
| 35 |
C momentum equations set it CPP_OPTIONS.h; the following line |
| 36 |
C even overrides setting the flag in CPP_OPTIONS.h |
| 37 |
#undef ISOTROPIC_COS_SCALING |
| 38 |
|
| 39 |
C As of checkpoint41, the inclusion of multi-dimensional advection |
| 40 |
C introduces excessive recomputation/storage for the adjoint. |
| 41 |
C We can disable it here using CPP because run-time flags are insufficient. |
| 42 |
#undef DISABLE_MULTIDIM_ADVECTION |
| 43 |
|
| 44 |
C This enable the use of 2nd-Order Moment advection scheme (Prather, 1986) for |
| 45 |
C Temperature and Salinity ; due to large memory space (10 times more / tracer) |
| 46 |
C requirement, by default, this part of the code is not compiled. |
| 47 |
#undef GAD_ALLOW_TS_SOM_ADV |
| 48 |
|
| 49 |
C Hack to get rid of negatives caused by Redi. Works by restricting the |
| 50 |
C outgoing flux (only contributions computed in gad_calc_rhs) for each cell |
| 51 |
C to be no more than the amount of tracer in the cell (see Smolarkiewicz |
| 52 |
C MWR 1989 and Bott MWR 1989). |
| 53 |
C The flux contributions computed in gad_calc_rhs which are affected by |
| 54 |
C this hack are: |
| 55 |
C - explicit diffusion, Redi and the non-local part of KPP |
| 56 |
C - advection is affected only if multiDimAdvection=.FALSE. |
| 57 |
C - vertical diffusion (including the diagonal contribution from GMRedi) |
| 58 |
C only if implicitDiffusion=.FALSE. |
| 59 |
C - GM is affected only if GMREDI_AdvForm=.FALSE. |
| 60 |
C |
| 61 |
C The parameter SmolarkiewiczMaxFrac (defined in gad_init_fixed.F) |
| 62 |
C specifies the maximal fraction of tracer that can leave a cell. |
| 63 |
C By default it is 1. This will prevent the tracer from going negative |
| 64 |
C due to contributions from gad_calc_rhs alone. In the presence of other |
| 65 |
C contributions (or roundoff errors), it may be necessary to reduce this |
| 66 |
C value to achieve strict positivity. |
| 67 |
C |
| 68 |
C This hack applies to all tracers except temperature and salinity! |
| 69 |
C Do not use with Adams-Bashforth (for ptracers)! |
| 70 |
C Do not use with OBCS! |
| 71 |
#undef GAD_SMOLARKIEWICZ_HACK |
| 72 |
|
| 73 |
#else |
| 74 |
|
| 75 |
C If GAD is disabled then so is multi-dimensional advection |
| 76 |
#define DISABLE_MULTIDIM_ADVECTION |
| 77 |
|
| 78 |
#endif /* ALLOW_GENERIC_ADVDIFF */ |
| 79 |
#endif /* GAD_OPTIONS_H */ |
Parent Directory
| 
Revision Log
| 
Revision Graph