oggm.tasks.catchment_area

oggm.tasks.catchment_area(gdir)

Compute the catchment areas of each tributary line.

The idea is to compute the route of lowest cost for any point on the glacier to rejoin a centerline. These routes are then put together if they belong to the same centerline, thus creating “catchment areas” for each centerline.

Parameters

gdiroggm.GlacierDirectory

where to write the data

Notes

Files written to the glacier directory:

geometries.pkl

A dictionary containing the shapely.Polygons of a glacier. The “polygon_hr” entry contains the geometry transformed to the local grid in (i, j) coordinates, while the “polygon_pix” entry contains the geometries transformed into the coarse grid (the i, j elements are integers). The “polygon_area” entry contains the area of the polygon as computed by Shapely. The “catchment_indices” entrycontains a list of len n_centerlines, each element containing a numpy array of the indices in the glacier grid which represent the centerlines catchment area.