103 | | * Only handles latitude/longitude grids (with possible rotation). |
104 | | * Does not make use of flexibility of BDY module - only handles regular rectangular boundaries at edge of the domain. |
105 | | 1. Coordinates |
106 | | An IDL routine takes the model bathymetry as input (see 4.3) and generates the NEMO coordinates.nc file as well as the grid definition files required by the SCRIP routines. Note that this routine can only handle latitude/longitude grids with possible rotation. |
107 | | 1. Bathymetry |
108 | | Bathymetry on the model domain is derived from the GEBCO dataset using a box-averaging algorithm, ie. all data points within a model gridbox are averaged to find the model depth at that point. IDL code. Bathmetry at open boundaries is matched to the bathymetry of the low-resolution model supplying the boundary data. Sometimes hand editing of the bathymetry is performed, eg. to remove nearly-enclosed inlets on the coast. Bathymetry for the North-West Shelf domain is derived from the NOOS 1 nautical mile bathymetry using grid-box averaging. |
109 | | 1. Boundary condition + Tide |
110 | | An IDL routine takes the model coordinates.nc le as input and generates the coordinates.bdy.nc file (definition of boundary in BDY module) as well as the grid definition files required by SCRIP. Note that this routine can only handle regular open boundaries around the edge of a rectangular domain, so doesn't make use of the flexibility of the boundary zone definition in BDY. |
111 | | Boundary data is generated using 3D linear interpolation. Tidal harmonic forcing data is interpolated from output from a tidal model. |
112 | | 1. Initial condition |
113 | | Regional models are spun up from rest. Initial temperature and salinity fields are either taken from climatology or from a low-resolution FOAM analysis. The temperature and salinity fields are interpolated to the model grid using 3D linear interpolation. |
114 | | 1. Runoff |
115 | | Runoff is generated from the GRDC climatological dataset using a set of bespoke scripts and fortran code. For each river the data point nearest to the coast is selected and applied to the nearest coastal point in the model. For large rivers the runoff is spread over a number of ocean points. Runoff is applied as a surface flux. |
| 100 | * Only handles latitude/longitude grids (with possible rotation). |
| 101 | * Does not make use of flexibility of BDY module - only handles regular rectangular boundaries at edge of the domain. |
| 102 | 1. Coordinates An IDL routine takes the model bathymetry as input (see 4.3) and generates the NEMO coordinates.nc file as well as the grid definition files required by the SCRIP routines. Note that this routine can only handle latitude/longitude grids with possible rotation. |
| 103 | 1. Bathymetry Bathymetry on the model domain is derived from the GEBCO dataset using a box-averaging algorithm, ie. all data points within a model gridbox are averaged to find the model depth at that point. IDL code. Bathmetry at open boundaries is matched to the bathymetry of the low-resolution model supplying the boundary data. Sometimes hand editing of the bathymetry is performed, eg. to remove nearly-enclosed inlets on the coast. Bathymetry for the North-West Shelf domain is derived from the NOOS 1 nautical mile bathymetry using grid-box averaging. |
| 104 | 1. Boundary condition + Tide An IDL routine takes the model coordinates.nc le as input and generates the coordinates.bdy.nc file (definition of boundary in BDY module) as well as the grid definition files required by SCRIP. Note that this routine can only handle regular open boundaries around the edge of a rectangular domain, so doesn't make use of the flexibility of the boundary zone definition in BDY. Boundary data is generated using 3D linear interpolation. Tidal harmonic forcing data is interpolated from output from a tidal model. |
| 105 | 1. Initial condition Regional models are spun up from rest. Initial temperature and salinity fields are either taken from climatology or from a low-resolution FOAM analysis. The temperature and salinity fields are interpolated to the model grid using 3D linear interpolation. |
| 106 | 1. Runoff Runoff is generated from the GRDC climatological dataset using a set of bespoke scripts and fortran code. For each river the data point nearest to the coast is selected and applied to the nearest coastal point in the model. For large rivers the runoff is spread over a number of ocean points. Runoff is applied as a surface flux. |
125 | | 1. required input files: high resolution bathymetry (usually 1/2km), coast line (100m resolution); |
126 | | 1. define the region and the discretization step (lat, lon, delta-lat, delta-lon); |
127 | | 1. define kind of vertical discretization, zeta, sigma; |
128 | | 1. we usually define a regular horizontal mesh; |
129 | | 1. interpolate bathymetry into the model mesh (biliniar interpolation); |
130 | | 1. define number of vertical levels and they distribution: we usually make use of zeta coord with partial step. |
131 | | For this case, in order to fix the vertical levels distribution we use ocean observations (CTD, XBT and ARGO). |
132 | | We interpolate the obs data into several vertical grids generated using NEMO algorithm and then back to the original grid (usually 1m resolution); |
133 | | we check for the vertical grid providing smaller interpolation error and able to reproduce the vertical water mass distribution; |
134 | | when sigma coordinates are used we compute hydrostatic consistency factor and smooth (simple laplacian filter) the topography accordingly; |
135 | | 1. define minimum depth; |
136 | | 1. refine land-sea mask on the base of the coast-line dataset (matlab GUI); The idea is to preserve realistic coast line despite the minimum depth; |
| 115 | 1. required input files: high resolution bathymetry (usually 1/2km), coast line (100m resolution); |
| 116 | 1. define the region and the discretization step (lat, lon, delta-lat, delta-lon); |
| 117 | 1. define kind of vertical discretization, zeta, sigma; |
| 118 | 1. we usually define a regular horizontal mesh; |
| 119 | 1. interpolate bathymetry into the model mesh (biliniar interpolation); |
| 120 | 1. define number of vertical levels and they distribution: we usually make use of zeta coord with partial step. For this case, in order to fix the vertical levels distribution we use ocean observations (CTD, XBT and ARGO). We interpolate the obs data into several vertical grids generated using NEMO algorithm and then back to the original grid (usually 1m resolution); we check for the vertical grid providing smaller interpolation error and able to reproduce the vertical water mass distribution; when sigma coordinates are used we compute hydrostatic consistency factor and smooth (simple laplacian filter) the topography accordingly; |
| 121 | 1. define minimum depth; |
| 122 | 1. refine land-sea mask on the base of the coast-line dataset (matlab GUI); The idea is to preserve realistic coast line despite the minimum depth; |
138 | | 1. required input file: observations, already existing mapped climatology (SeaDataNet, MedAtlas), or parent model results; |
139 | | 1. In case of sparse observation we do Objective Analysis to map the data into the model grid. in case of already existing mapped data we do a simple linear interpolation; |
140 | | 1. after the IC file is created we check for vertical stability and correct if necessary; |
| 124 | 1. required input file: observations, already existing mapped climatology (SeaDataNet, MedAtlas), or parent model results; |
| 125 | 1. In case of sparse observation we do Objective Analysis to map the data into the model grid. in case of already existing mapped data we do a simple linear interpolation; |
| 126 | 1. after the IC file is created we check for vertical stability and correct if necessary; |
149 | | * we could change the number of vertical levels |
150 | | * we could change z-coordinaltes to s-coordinates |
151 | | * we could change grid orca to regular |
152 | | However, It may not allow to keep U, V point on the boundary. |
| 135 | * we could change the number of vertical levels |
| 136 | * we could change z-coordinaltes to s-coordinates |
| 137 | * we could change grid orca to regular However, It may not allow to keep U, V point on the boundary. |
| 142 | 1. Coordinates |
| 143 | || input || function || tool || advantage || inconvenience || |
| 144 | || '''low resolution coordinates''' || refine ORCA grid || AGRIF_create_coordinates || || || |
| 145 | || || || GRIDGEN || || || |
| 146 | || || || BMGtools|| || || |
| 147 | || '''high resolution coordinates''' || extract ORCA grid || Mercator Fortran code || || || |
| 148 | || || || GRIDGEN || || || |
| 149 | || || || BMGtools|| || || |
| 150 | || '''low resolution bathymetry''' || create regular grid || MetOffice IDL tools || || | |
| 151 | 2. Bathymetry |
| 152 | || input || function || tool || advantage || inconvenience || |
| 153 | || '''bathymetry dateset''' || create bathymetry on grid || OPABAT || || || |
| 154 | || || || MetOffice IDL tools || || || |
| 155 | || || || BMGtools, based on SCRIPP3D || || || |
| 156 | || || || AGRIF_create_bathy || || || |
| 157 | || '''low resolution bathymetry''' || refine bathymetry || BMGtools || || || |
| 158 | || || || AGRIF_create_bathy || || || |
| 159 | || '''high resolution bathymetry''' || extract bathymetry || Mercator Fortran code || || | |
| 160 | 3. Boundary Condition |
| 161 | || input || function || tool || advantage || inconvenience || |
| 162 | || '''low resolution climatolgy or analysis''' || interpolation to rectangular boundaries || SCRIP and MetOffice IDL tools || || || |
| 163 | || || || Mercator Fortran code || || || |
| 164 | || || interpolation to unstructured boundary || NOC python tools || || || |
| 165 | 4. Initial Conndition |
| 166 | || input || function || tool || advantage || inconvenience || |
| 167 | || '''low resolution climatolgy or analysis''' || interpolation of T, S and start from rest || MetOffice IDL tools || || || |
| 168 | || '''low resolution climatolgy, analysis or restart''' || split restart and/or interpolation of T, S, U, V, SSH || Mercator Fortran code || || || |
| 169 | 5. Runoff |
| 170 | || input || function || tool || advantage || inconvenience || |
| 171 | || '''low resolution climatology''' || as surface flux, on nearest coastal point, large rivers spread over ocean points || MetOffice Fortran code || || || |
| 172 | || || as surface flux, spread on coastal points, large rivers spread over ocean masks. || Mercator Fortran code || || || |
| 173 | || || as surface flux, spread on coastal points, and as BDY large rivers. || Mercator Fortran code || || || |
| 174 | 6. Surface Forcing |
| 175 | || input || function || tool || advantage || inconvenience || |
| 176 | || '''low resolution climatology or analysis''' || interpolation on the fly || fldread || || || |