Regions

Region Config Section

The [regions] section of a configuration file contains options related to regions either defined in MPAS components’ online analysis or determined within MPAS-Analysis using region mask files:

[regions]
## options related to ocean regions used in several analysis modules

# list of region names (needs to be in the same order as region indices in
# time-series stats)
regions = ['arctic', 'equatorial', 'so', 'nino3', 'nino4', 'nino3.4', 'global']
# list of plot titles (needs to be in the same order as region indices in
# time-series stats)
plotTitles = ['Arctic', 'Equatorial (15S-15N)', 'Southern Ocean', 'Nino 3',
              'Nino 4', 'Nino 3.4', 'Global Ocean']

MPAS-Ocean currently has hard coded into its online analysis 7 regions in a fixed order, as given in the regions option. This should not be altered unless corresponding changes to the MPAS-Ocean code have been made.

The corresponding plotTitles can be modified as desired to update how these regions are named in plot titles and in gallery names on the resulting web page.

Region Groups

Currently, seven analysis tasks (climatologyMapAntarcticMelt, hovmollerOceanRegions, oceanRegionalProfiles, regionalTSDiagrams, streamfunctionMOC, timeSeriesAntarcticMelt, and timeSeriesOceanRegions) use masks that define regions in an MPAS mesh as part of their analysis. Most of these region group are defined in geometric_features.aggregation.get_aggregator_by_name(). Several tasks (hovmollerOceanRegions, oceanRegionalProfiles, regionalTSDiagrams, and timeSeriesOceanRegions) can use any of the defined region groups. Currently, available region groups are: Antarctic Regions, Ocean Basins, Ice Shelves, and Ocean Subbasins.

The option regionMaskSubdirectory in the [diagnostics] section specifies the path to cached mask files for these region groups, typically diagnostics/mpas_analysis/region_masks. Region masks for common MPAS Ocean and Seaice meshes are supplied as part of the data from the E3SM public data repository (see the Quick Start Guide).

If masks for for a given grid don’t already exist in the cached mask location, they will be generated automatically from the aggregation function from the geometric_features package, see Aggregate Existing Features. The mask data will be stored in a geojson file with the region group’s prefix and date stamp (e.g. iceShelves20200621.geojson). Then, masks on the MPAS Ocean and Seaice mesh will be computed, a process that can be time consuming for large meshes. To generate the masks in advance (using threading to speed up the process), see the example utility script utility_scripts/make_region_mask.py.