Bathymetry — available datasets

The bathymetry backend ships three curated DEM rows. Pick one with the dataset= argument. Every row is a static global elevation grid served as a NOAA ERDDAP griddap coverage, with a single elevation band in metres relative to sea level (negative = below sea level).

dataset=	DEM	Native resolution	Band	Longitude	Server
gebco_2020	GEBCO 2020 (topography + bathymetry)	15 arc-second	elevation	−180..180	NOAA CoastWatch ERDDAP
etopo1_ice	ETOPO1 global relief, Ice Surface	1 arc-minute	z	−180..180	NOAA upwell ERDDAP
etopo1_bedrock	ETOPO1 global relief, Bedrock	1 arc-minute	z	−180..180	NOAA upwell ERDDAP

The ETOPO variant is the dataset id, not a variables knob: choose etopo1_ice for the top of the ice sheets or etopo1_bedrock for their base.

Facade aliases

Two friendly aliases route to the same backend, so a script reads the way you think about the data:

• data_source="gebco" — then pass dataset="gebco_2020".
• data_source="etopo" — then pass dataset="etopo1_ice" or dataset="etopo1_bedrock".

data_source="bathymetry" works with any of the three dataset= ids.

Listing the ids programmatically

from earthlens.bathymetry import Catalog

catalog = Catalog()
sorted(catalog.datasets)        # ['etopo1_bedrock', 'etopo1_ice', 'gebco_2020']
catalog.get("gebco_2020").variable      # 'elevation'
catalog.get("etopo1_ice").native_resolution    # '1 arc-minute'

Versions

These are the versions cleanly subsettable over the public ERDDAP griddap transport today (GEBCO 2020 and ETOPO1). Newer releases (ETOPO 2022, later GEBCO grids) are not exposed as a bbox-subsettable ERDDAP coverage on the public hosts; when they are, they can be added as extra catalog rows without any backend change.