Global terrain model for ocean and land at 15 arc-second (~450 m at the equator), elevation in metres relative to mean sea level (sub-ice grid). Source: GEBCO Compilation Group (2025).
The hex layer is H3 resolution 8, one row per h8 cell, hive-partitioned by h0,
with parent indexes h7/h6/h5. elevation is the area-weighted mean elevation per
cell (negative = below sea level). Complete global coverage (GEBCO has no nodata gaps).
Re-hexed on the antimeridian/polar-fixed pipeline (boettiger-lab/datasets #88/#92/#93,
data-workflows #186).
elevation is an intensity — aggregate with AVG/MIN/MAX, never SUM.
Global range: −10,930 m (Mariana Trench) to 8,627 m; area-weighted mean ≈ −2,470 m.
GEBCO Compilation Group (2025). The GEBCO_2025 Grid — a continuous terrain model of the global oceans and land. doi:10.5285/... (see gebco.net).