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16.4 Summary of options

The following options are used by module grids when executing in a stand alone mode. They are enabled by compiling with options of the form -Doption1 -Doption1 ...as in script run_grids.

drive_grids turns on a small driver which allows the module grids to be executed in a simple environment (stand alone). This is only used for designing grids with the script run_grids. It is not appropriate when executing MOM.
generate_a_grid generates a grid based on specifications in the USER INPUT section of module grids. It is used both in the script run_grids and when executing MOM.
read_my_grid allows grids developed elsewhere to be imported into MOM.
write_my_grid writes a copy of the grid information to file grid.dta.out.
centered_t constructs a grid using method 1 from Section 16.2.3. If not enabled, the grid is constructed using method 2 from Section 16.2.3 which is different than the way it has been constructed in previous versions of the model.
isotropic_grid constructs a square grid between two bounding latitudes.
extend_isotropic_grid extends the isotropic grid to the poles using a nearly constant $\Delta_y$ .
bbl_ag modifies the vertical grid to account for a bottom boundary layer.
symmetry used when specifying a symmetry condition at the northern boundary of the domain. Note that symmetry can only be specified when the northern part of the domain is at the equator.

**Figure 16.1:** a) A region bounded by two longitudes. b) A region bounded by two latitudes. c) A region bounded by two depths.
$\begin{figure} \begin{center} \resizebox{15cm}{!}{\includegraphics{grid_bounds.ps}}\end{center}\end{figure}$

**Figure 16.2:** a) Horizontal resolution of grid cells. b) Grid cell arrangement on a longitude-latitude surface of constant depth.
$\begin{figure} \begin{center} \resizebox{15cm}{!}{\includegraphics{grid_xy.ps}}\end{center}\end{figure}$

**Figure 16.3:** a) Vertical resolution of grid cells. b) Grid cell arrangement on a longitude-depth surface of constant latitude.
$\begin{figure} \begin{center} \resizebox{15cm}{!}{\includegraphics{grid_xz.ps}}\end{center}\end{figure}$

**Figure 16.4:** a) Vertical resolution of grid cells. b) Grid cell arrangement on a latitude-depth surface of constant longitude.
$\begin{figure} \begin{center} \resizebox{15cm}{!}{\includegraphics{grid_yz.ps}}\end{center}\end{figure}$

**Figure 16.5:** Comparison of two grid cell construction methods applied in the vertical dimension. Method 2 is the default in MOM.
$\begin{figure} \begin{center} \resizebox{15cm}{!}{\includegraphics{grid_4.ps}}\end{center}\end{figure}$

Next: 17. Grid Rotation Up: 16. Grids Previous: 16.3.1 Grids in two

RC Pacanowski and SM Griffies, GFDL, Jan 2000