1 |
C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/GAD_OPTIONS.h,v 1.16 2013/03/04 18:20:46 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 Use this file for selecting options within the GAD package |
16 |
|
17 |
#ifndef GAD_OPTIONS_H |
18 |
#define GAD_OPTIONS_H |
19 |
#include "PACKAGES_CONFIG.h" |
20 |
#include "CPP_OPTIONS.h" |
21 |
|
22 |
#ifdef ALLOW_GENERIC_ADVDIFF |
23 |
C Package-specific Options & Macros go here |
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 Use compressible flow method for multi-dim advection instead of old, less |
45 |
C accurate jmc method. Note: option has no effect on SOM advection which |
46 |
C always use compressible flow method. |
47 |
#define GAD_MULTIDIM_COMPRESSIBLE |
48 |
|
49 |
C This enable the use of 2nd-Order Moment advection scheme (Prather, 1986) for |
50 |
C Temperature and Salinity ; due to large memory space (10 times more / tracer) |
51 |
C requirement, by default, this part of the code is not compiled. |
52 |
#define GAD_ALLOW_TS_SOM_ADV |
53 |
|
54 |
C Hack to get rid of negatives caused by Redi. Works by restricting the |
55 |
C outgoing flux (only contributions computed in gad_calc_rhs) for each cell |
56 |
C to be no more than the amount of tracer in the cell (see Smolarkiewicz |
57 |
C MWR 1989 and Bott MWR 1989). |
58 |
C The flux contributions computed in gad_calc_rhs which are affected by |
59 |
C this hack are: |
60 |
C - explicit diffusion, Redi and the non-local part of KPP |
61 |
C - advection is affected only if multiDimAdvection=.FALSE. |
62 |
C - vertical diffusion (including the diagonal contribution from GMRedi) |
63 |
C only if implicitDiffusion=.FALSE. |
64 |
C - GM is affected only if GMREDI_AdvForm=.FALSE. |
65 |
C |
66 |
C The parameter SmolarkiewiczMaxFrac (defined in gad_init_fixed.F) |
67 |
C specifies the maximal fraction of tracer that can leave a cell. |
68 |
C By default it is 1. This will prevent the tracer from going negative |
69 |
C due to contributions from gad_calc_rhs alone. In the presence of other |
70 |
C contributions (or roundoff errors), it may be necessary to reduce this |
71 |
C value to achieve strict positivity. |
72 |
C |
73 |
C This hack applies to all tracers except temperature and salinity! |
74 |
C Do not use with Adams-Bashforth (for ptracers)! |
75 |
C Do not use with OBCS! |
76 |
#undef GAD_SMOLARKIEWICZ_HACK |
77 |
|
78 |
#else |
79 |
|
80 |
C If GAD is disabled then so is multi-dimensional advection |
81 |
#define DISABLE_MULTIDIM_ADVECTION |
82 |
|
83 |
#endif /* ALLOW_GENERIC_ADVDIFF */ |
84 |
#endif /* GAD_OPTIONS_H */ |