Creating Grids with MAPL Grid Factories

From an ESMF config file

An ESMF config object can be passed into the a grid factory to create a factory for an ESFM grid. Currently a Lat-Lon, Tripolar, and Cubed-Sphere grids are supported via a factory. The general format in the file is as follows:

grid_identifier.option1
grid_identifier.option2
.
.
.

The grid_identifier is a unique name that is passed as part of the factory interface. The factory searches for entries that are proceeded by the grid_identifier. Then there is a "." that separates the grid identifier from the keywords that are specific to each grid factory. Note each grid factory should have a GRID_TYPE keyword so that the correct grid factory can be invoked if using the MAPL_GridManager to manage multiple grids. The options for each grid factory will be enumerated in the following sections.

Lat-Lon Grid

* GRIDNAME: the name that will be supplied to the ESMF grid creation
* NX: size of the domain decomposition in the i direction
* NY: size of the domain decomposition in the j direction
* IM_WORLD: global size of the grid in the i direction
* JM_WORLD: global size of the grid in the j direction
* LM: size of the grid in the vertical (note that the ESFM grid is a 2-D, this is simply attached as an attribute for connivence)
* POLE: how to handle the pole, options are 'PE', edge of the grid cell on the pole. 'PC' both the center and edge points are at the pole. 'XY' used for a regional grid