Major TOM Core-DEM contains a global coverage of Copernicus DEM, each of size 352 x 352 pixels.
Global Digital Surface Model coverage from Copernicus DEM GLO-30 on the Major TOM grid. Each sample is a 10 km cell of 352 × 352 pixels at 30 m, in the UTM zone of the cell and on its own origin.
Each sample carries the metadata below, plus rumi:header and rumi:stats
(per-band minimum, maximum, mean, standard deviation and counts) on the file.
The sample id is the Major TOM 10 km cell, for example MT10km_0104D_0845L.
It is the same string as majortom:code and identifies the cell anywhere the
grid is used.
Global and monotemporal, over the land cells of the Major TOM grid. 674,495 of the samples (38.9%) are entirely water: 457,527 fall outside Copernicus DEM coverage, and the rest are covered by a tile that is itself zero over water.
Nothing is unpacked first. The query is answered from the catalog, and only the
byte ranges of the selected samples are read. dataset is one row per sample,
with a ::location and a ::header column per file; the metadata levels are
also available by name, as sample and children.
Requires taco-eo 0.10 or newer.
Copernicus DEM GLO-30 was read from the public COGs on S3 and resampled with nearest neighbour onto each cell's own UTM grid, taking every tile the cell touches. The 10,560 m cell divides exactly by 30 m, so the pixels land on the cell boundary without a half-pixel offset.
Elevation is stored as int16 metres and compressed with
GeoZL using
med>zigzag>transpose>entropy under a LINEAR bound of 2 m, chosen by profiling
64 candidate graphs on real cells. Water is zero rather than a nodata sentinel,
which is the convention Copernicus already uses inside its own tiles; LINEAR
quantization is anchored at zero, so those values survive exactly.
The Major TOM grid and the first Core-DEM release are a collaboration between ESA Φ-lab and Adobe Research, compiled by Paul Borne--Pons under the supervision of Mikolaj Czerkawski and Alistair Francis. This release was rebuilt and packaged by Asterisk Labs.
Copernicus WorldDEM-30 © DLR e.V. 2010-2014 and © Airbus Defence and Space GmbH 2014-2018, provided under the Copernicus DEM open licence.