rockhound.fetch_bedmap2

rockhound.fetch_bedmap2(datasets, *, load=True, chunks=1000, **kwargs)[source]

Fetch the Bedmap2 datasets for Antarctica.

Bedmap2 is a suite of gridded products describing surface elevation, ice-thickness, the sea floor and subglacial bed elevation of the Antarctic south of 60°S [BEDMAP2]. The datasets are downloaded as tiff files and loaded into a xarray.Dataset object.

Each dataset is projected in Antarctic Polar Stereographic projection, latitude of true scale -71 degrees south, datum WGS84. All heights are in metres relative to sea level as defined by the g104c geoid.

The available datasets are:

  • bed: bedrock height

  • surface: ice surface height

  • thickness: ice thickness

  • icemask_grounded_and_shelves: mask showing the grounding line and the extent of the floating ice shelves

  • rockmask: mask showing rock outcrops

  • lakemask_vostok: mask showing the extent of the lake cavity of Lake Vostok

  • grounded_bed_uncertainty: ice bed uncertainty grid

  • thickness_uncertainty_5km: ice thickness uncertainty grid

  • coverage: binary grid showing the distribution of ice thickness data used in the grid of ice thickness

  • geoid: values to convert from heights relative to WGS84 datum to heights relative to EIGEN-GL04C geoid (to convert back to WGS84, add this grid)

Warning

Loading datasets into memory may require a fair amount of memory. In order to prevent this, the function loads the datasets as Dask arrays if chunks is not None. Be careful when doing operations that loads the entire datasets into memory, like plotting or performing some computations.

Warning

Loading any dataset along with thickness_uncertainty_5km would modify the shape of the grid because it’s defined on a different set of points.

Parameters

  • datasets (list or str) – Names of the datasets that will be loaded from the Bedmap2 model.

  • load (bool) – Whether to load the data into an xarray.Dataset or just return the path to the downloaded data tiff files. If False, will return a list with the paths to the files corresponding to datasets.

  • chunks (int, tuple or dict) – Chunk sizes along each dimension. This argument is passed to the xarray.open_rasterio function in order to obtain Dask arrays inside the returned xarray.Dataset. This helps to read the dataset without loading it entirely into memory.

  • **kwargs – Extra parameters passed to the xarray.open_rasterio function.

Returns

grid (xarray.Dataset) – The loaded Bedmap2 datasets.