| | 23 | |
| | 24 | |
| | 25 | == Automatic contruction of the files == |
| | 26 | |
| | 27 | |
| | 28 | The construction schedules of the outline file of bathymetry were conceived for fields of the model with relative small dimension, 100x100 with 1000x1000 points on the horizontal one, based on the handling of large data files and on expensive interpolations in computing times. These programs were initially conceived in 1993 to build the bathymetry of the first version world ocean OPA and were based on a set of FORTRAN programs and programs of layouts NCAR to validate the results. They were re-examined into 1997/98 per Anne-Marie Tréguier (LPO) within the framework of the CLIPPER project and with the LODYC for construction, inter alia, of the bathymetry for model ORCA. The graphic part and certain developments was given up or appreciably modified by the use of IDL which adds employment opportunities, in particular the use of the mouse. The programs, developed in FORTRAN 77 for an initial application, then used in several other contexts of the years afterwards, do not present the desired finished aspect and comprise sometimes abandoned developments, obsolete comments and certainly of the errors which we will perhaps have time and courage to begin again.[[BR]] |
| | 29 | |
| | 30 | Up to now, two data files of bathymetry were used :[[BR]] |
| | 31 | |
| | 32 | - ETOP5[[BR]] |
| | 33 | Released by the Marine Geology and Geophysics Division/National Geophysical Dated Center, covering the sphere and 5 minutes per 5 minutes of[[BR]] |
| | 34 | |
| | 35 | {{{ |
| | 36 | PARAMETER( JPITP5 = 4320, JPJTP5 = 2160 ) |
| | 37 | }}} |
| | 38 | |
| | 39 | - Smith and Sandwel[[BR]] |
| | 40 | file covering the sphere of 72 S with 72 N and integrating the recent data satellitales, 2 minutes resolution per 2 minutes: [[BR]] |
| | 41 | |
| | 42 | (David T. Sandwell, Walter H. F. Smith, Stuart M. Smith, and Christopher Small,[[BR]] |
| | 43 | |
| | 44 | Institute for Geophysics and Planetary Physics, SIO, Geodynamics Laboratory, NOAA - Geological Data Center, SIO - Lamont Doherty Earth Observatory)[[BR]] |
| | 45 | |
| | 46 | (look at [http://topex.ucsd.edu/marine_topo/mar_topo.html http://topex.ucsd.edu/marine_topo/mar_topo.html] ).[[BR]] |
| | 47 | |
| | 48 | |
| | 49 | {{{ |
| | 50 | PARAMETER( JPIBAT = 10800, JPJBAT = 6336) |
| | 51 | }}} |
| | 52 | |
| | 53 | |
| | 54 | Nota bene : If the field of the model covers areas in high latitudes, it is necessary to resort simultaneously to the two files.[[BR]] |
| | 55 | |
| | 56 | Two methods of interpolation are employed:[[BR]] |
| | 57 | |
| | 58 | A bilinear interpolation using the four points of data framing the point of grid.[[BR]] |
| | 59 | Variable lopa_method=.false. in the namelist file.[[BR]] |
| | 60 | |
| | 61 | An average of the data of bathymetry contained in an areaof the grid of the model.[[BR]] |
| | 62 | Variable lopa_method=.true. in the namelist file.[[BR]] |
| | 63 | |
| | 64 | This last method is more complex to carry out when the model uses an irregular grid with a symmetry east- west. It is recommended when the model is of weak resolution. The bilinear method is necessary when the resolution approaches the resolution of the data, the averages becoming nonsignificant.[[BR]] |
| | 65 | |
| | 66 | To use IDL utility, it is necessary to build two files of outline of bathymetry, i.e. to carry out these programs twice to obtain a file with the resolution of the model, a file of highher resolution which will be used as file of control in the choices of the levels of bathymetry and will replace the use of the initial files of topography which are often difficult to handle and covering all the sphere. Typically the file of the model will be built by using an average by area, the file of control, to which the resolution is closer to the data, with a bilinear interpolation.[[BR]] |
| | 67 | |
| | 68 | Example of parameters used for the construction of the bathymetry of configuration ORCA :[[BR]] |
| | 69 | |
| | 70 | |
| | 71 | {{{ |
| | 72 | CC MODEL DATA SIZE |
| | 73 | |
| | 74 | CC --------------- |
| | 75 | |
| | 76 | CC JPI : FIRST HORIZONTAL DIMENSION |
| | 77 | |
| | 78 | CC JPJ : SECOND |
| | 79 | |
| | 80 | CC JPK : NUMBER OF VERTICAL LEVELS |
| | 81 | |
| | 82 | CC |
| | 83 | |
| | 84 | INTEGER jpiglo,jpjglo,jpidta,jpjdta,jpi,jpj,jpk |
| | 85 | |
| | 86 | PARAMETER(JPIGLO = 182,JPJGLO = 149) |
| | 87 | |
| | 88 | C |
| | 89 | }}} |
| | 90 | |
| | 91 | Second execution, bathymetry of finer resolution, in the case of ORCA, the precision was increased by a factor 12 in both direction of space thus a point of bathymetry is compared with a whole of 144 values :[[BR]] |
| | 92 | |
| | 93 | {{{ |
| | 94 | INTEGER NRES |
| | 95 | |
| | 96 | PARAMETER(NRES=12) |
| | 97 | |
| | 98 | C si haute resolution |
| | 99 | |
| | 100 | PARAMETER(JPIGLO = 182*NRES,JPJGLO = 149*NRES) |
| | 101 | |
| | 102 | PARAMETER(JPI = jpiglo,JPJ = jpjglo ) |
| | 103 | |
| | 104 | PARAMETER(JPIDTA = jpiglo,JPJDTA = jpjglo ). |
| | 105 | |
| | 106 | }}} |
| | 107 | |
| | 108 | The whole of the programs is called OPABAT :[[BR]] |
| | 109 | |
| | 110 | -OPABAT : main program, reading of the file namelist, call of the routines.[[BR]] |
| | 111 | -DOMHGR : programme OPA, définition de la grille horizontale et des facteurs d'échelle.[[BR]] |
| | 112 | -HGRCOO : program OPA, definition of the horizontal grid and scale factors.programme OPA lecture de la grille horizontale si NTOPO=1.[[BR]] |
| | 113 | -DOMZGR : program OPA, definition of the vertical grid.[[BR]] |
| | 114 | -DOMMSK : programe OPA , masks computing.[[BR]] |
| | 115 | -BATLEG : reading of the data file.[[BR]] |
| | 116 | -BATGUE : interpolation and creation of the outline file.[[BR]] |
| | 117 | -BATMOD : possible corrections of the file.[[BR]] |
| | 118 | -BATWRI : saving the file.[[BR]] |
| | 119 | |
| | 120 | A makefile allows to obtain a binary.[[BR]] |
| | 121 | |
| | 122 | A file opabat.h allows to initialize the size of arrays.[[BR]] |
| | 123 | |
| | 124 | The namelist file allows to initialize the context of the experiment and the choice of the variables.[[BR]] |
| | 125 | |
| | 126 | Nota Bene :[[BR]] |
| | 127 | |
| | 128 | The files of bathymetry have as a unit the levels of model, the file of outline is in whole value varying from 0 (ground) with jpk, ocean floor.[[BR]] |
| | 129 | The file of control is to express in floating value between 0. and float(jpk), to see program batwri.[[BR]] |
| | 130 | |
| | 131 | |
| | 132 | |
