Aggregate Existing Features

The geometric_features.aggregation module contains functions used to aggregate existing features to make new, larger ones. An example usage of these aggregation functions is to create masks for regional averaging.

The function geometric_features.aggregation.get_aggregator_by_name() can be used to get information about one of the aggregated features by one of the following group names:

  • Antarctic Regions

  • Arctic Ocean Regions

  • Arctic Sea Ice Regions

  • ISMIP6 Greenland Regions

  • NASA Greenland Regions

  • Ocean Basins

  • Ice Shelves

  • Ocean Subbasins

  • Historical Sea Ice

  • ISMIP6 Regions

  • Transport Transects

This function returns the function that will aggregate the requested group, a prefix for the group (a modified version of the group name) and a date stamp that is updated each time the features in the group are changed. This way, mask files can be created from these features with filenames that include the date stamp. As long as the date stamp has not changed, these cached mask files can be reused.

Aggregating Ocean Features

Ocean Sub-basins

The function geometric_features.aggregation.ocean.subbasins() aggregates oceanic regions to make the following ocean subbasins: North and South Atlantic, North and South Pacific, Indian Basin, Arctic Basin, and Southern Ocean Basin.

_images/subbasins.png

Ocean Basins

The function geometric_features.aggregation.ocean.basins() aggregates oceanic regions to make the following ocean basins: Atlantic, Pacific, Indian, Arctic, Southern Ocean, Mediterranean, Global Ocean, Global Ocean 65N to 65S, Global Ocean 15S to 15N.

Meridional Overturning Circulation Basins

The function geometric_features.aggregation.ocean.moc() aggregates basins for computing the MOC: Atlantic, IndoPacific, Pacific and Indian

Arctic Regions

The function geometric_features.aggregation.ocean.arctic() aggregates regions of the Arcic (and subArctic): Baffin Bay, Baltic Sea, Barents Sea, Beaufort Gyre, Beaufort Gyre Shelf, Canada Basin, Canadian Archipelago, Central Arctic, Chukchi Sea, East Siberian Sea, Greenland Sea, Hudson Bay, Irminger Sea, Kara Sea, Labrador Sea, Laptev Sea, North Sea, Norwegian Sea, and Arctic Ocean - no Barents, Kara Seas.

Antarctic Regions

The function geometric_features.aggregation.ocean.antarctic() aggregates regions of the Antarctic: Southern Ocean, Southern Ocean 60S, Eastern Weddell Sea Shelf, Eastern Weddell Sea Deep, Western Weddell Sea Shelf, Western Weddell Sea Deep, Weddell Sea Shelf, Weddell Sea Deep, Bellingshausen Sea Shelf, Bellingshausen Sea Deep, Amundsen Sea Shelf, Amundsen Sea Deep, Eastern Ross Sea Shelf, Eastern Ross Sea Deep, Western Ross Sea Shelf, Western Ross Sea Deep, East Antarctic Seas Shelf, East Antarctic Seas Deep.

ISMIP6 Greenland Regions

The function geometric_features.aggregation.ocean.ismip6_greenland() aggregates regions of the continental shelves around Greenland based on the ISMIP6 regions: ISMIP6 Greenland Central East Shelf, ISMIP6 Greenland Central West Shelf, ISMIP6 Greenland North East Shelf, ISMIP6 Greenland North Shelf, ISMIP6 Greenland North West Shelf, ISMIP6 Greenland South East Shelf, ISMIP6 Greenland South West Shelf. Regions cover both landice and ocean, and could be used for either component.

NASA Greenland Regions

The function geometric_features.aggregation.landice.nasa_greenland() aggregates regions of Greenland drainage basins taken from NASA: (https://earth.gsfc.nasa.gov/cryo/data/polar-altimetry/antarctic-and-greenland-drainage-systems) The drainage basins have been altered to extend to the continental shelf break. Boundaries between basins have also been altered so that all glaciers terminating in an individual fjord are from the same drainage basin. Regions cover both landice and ocean, and could be used for either component.

Historical Sea Ice

The function geometric_features.aggregation.seaice.qgreenland() aggregates the historical monthly median sea ice extents taken from the QGreenland dataset (doi: doi:10.5281/zenodo.12823307): January Historical Median Sea Ice Extent, February Historical Median Sea Ice Extent, March Historical Median Sea Ice Extent, April Historical Median Sea Ice Extent, May Historical Median Sea Ice Extent, June Historical Median Sea Ice Extent, July Historical Median Sea Ice Extent, August Historical Median Sea Ice Extent, September Historical Median Sea Ice Extent, October Historical Median Sea Ice Extent, November Historical Median Sea Ice Extent, December Historical Median Sea Ice Extent.

Ice-shelf Regions

The function geometric_features.aggregation.ocean.ice_shelves() aggregates ice shelves and ice-shelf regions. There are 106 regions, so they won’t all be listed. See the resulting feature collection or the code itself for the full list.

Transport Transects

The function geometric_features.aggregation.ocean.transport() aggregates transport transects: Africa-Ant, Agulhas, Antilles Inflow, Barents Sea Opening, Bering Strait, Davis Strait, Drake Passage, Florida-Bahamas, Florida-Cuba, Fram Strait”, Indonesian Throughflow, Lancaster Sound, Mona Passage”, Mozambique Channel, Nares Strait, Tasmania-Ant Windward Passage.

Aggregating Sea-ice Features

Arctic Regions

The function geometric_features.aggregation.seaice.arctic() aggregates regions of the Arctic as defined by the National Snow and Ice Data Center (NSIDC) that are relevant for sea ice: Baffin Bay NSIDC, Barents Sea, Beaufort Sea NSIDC, Canadian Archipelago NSIDC, Central Arctic NSIDC, Chukchi Sea NSIDC, East Siberian Sea NSIDC, Hudson Bay NSIDC, Kara Sea, Laptev Sea NSIDC.