mom_grid_initialize module reference

Initializes horizontal grid.

Data Types

gps

Global positioning system (aka container for information to describe the grid)

Functions/Subroutines

`set_grid_metrics()`	set_grid_metrics is used to set the primary values in the model's horizontal grid. The bathymetry, land-sea mask and any restricted channel widths are not known yet, so these are set later.
`grid_metrics_chksum()`	grid_metrics_chksum performs a set of checksums on metrics on the grid for debugging.
`set_grid_metrics_from_mosaic()`	Sets the grid metrics from a mosaic file.
`set_grid_metrics_cartesian()`	Calculate the values of the metric terms for a Cartesian grid that might be used and save them in arrays.
`set_grid_metrics_spherical()`	Calculate the values of the metric terms that might be used and save them in arrays.
`set_grid_metrics_mercator()`	Calculate the values of the metric terms that might be used and save them in arrays.
`ds_di()`	This function returns the grid spacing in the logical x direction in [L ~> m].
`ds_dj()`	This function returns the grid spacing in the logical y direction in [L ~> m].
`dl()`	This function returns the contribution from the line integral along one of the four sides of a cell face to the area of a cell, in [radians2], assuming that the sides follow a linear path in latitude and longitude (i.e., on a Mercator grid).
`find_root()`	This subroutine finds and returns the value of y at which the monotonically increasing function fn takes the value fnval, also returning in ittmax the number of iterations of Newton's method that were used to polish the root.
`dx_di()`	This function calculates and returns the value of dx/di in [radian gridpoint-1], where x is the longitude in Radians, and i is the integral east-west grid index.
`int_di_dx()`	This function calculates and returns the integral of the inverse of dx/di to the point x, in radians [gridpoints].
`dy_dj()`	This subroutine calculates and returns the value of dy/dj in [radian gridpoint-1], where y is the latitude in Radians, and j is the integral north-south grid index.
`int_dj_dy()`	This subroutine calculates and returns the integral of the inverse of dy/dj to the point y in radians [gridpoints].
`extrapolate_metric()`	Extrapolates missing metric data into all the halo regions.
`adcroft_reciprocal()`	This function implements Adcroft's rule for reciprocals, namely that Adcroft_Inv(x) = 1/x for \|x\|>0 or 0 for x=0.
`initialize_masks()`	Initializes the grid masks and any metrics that come with masks already applied.

Detailed Description

The metric terms have the form Dzp, IDzp, or DXDYp, where z can be X or Y, and p can be q, u, v, or h. z describes the direction of the metric, while p describes the location. IDzp is the inverse of Dzp, while DXDYp is the product of DXp and DYp except that areaT is calculated analytically from the latitudes and longitudes of the surrounding q points.

On a sphere, a variety of grids can be implemented by defining analytic expressions for dx_di, dy_dj (where x and y are latitude and longitude, and i and j are grid indices) and the expressions for the integrals of their inverses in the four subroutines dy_dj, Int_dj_dy, dx_di, and Int_di_dx.

initialize_masks sets up land masks based on the depth field. The one argument is the minimum ocean depth. Depths that are less than this are interpreted as land points.

Type Documentation

type mom_grid_initialize/gps