The Pléiades Glacier Observatory (PGO) dataset collection is an initiative of the French Space Agency /
CNES, of the Laboratory of Space Geophysical and Oceanographic Studies /
LEGOS and of Institut National des Sciences de l'Univers / CNRS-INSU to facilitate access to
Pléiades satellite stereo-imagery and derived products for the glaciology community. The PGO program covers 141 glacier sites spread all over the globe with targeted acquisitions generally at the end of the melt season. The collection consists in Very-High Resolution (0.5m) Digital Surface Models (DSMs), map of elevation changes (dZ) and ortho-images. The first PGO campaigns took place in 2016 in the North Hemisphere and early 2017 in the South Hemisphere. Since 2021 in the northern Hemisphere and 2022 in the southern Hemisphere, the PGO has entered in revisit mode. Each site is being imaged again, allowing the production of elevation difference maps for each glacier every five years.
The products consist of :
- Collection PGO-DSM: DSMs at 2 m and 20 m spatial ground sampling distance. For the photogrammetric process, the Ames Stereo Pipeline (
Beyer & al., 2018[1]) is used with processing parameters from
Marti & al., 2016[2] for block matching -BM- and from
Deschamps & al., 2020[3] for semi global matching -SGM.
- Collection PGO-Ortho: Ortho-images, with a spatial resolution of 0.5 m (panchromatic) and 2 m (multispectral),
- Collection PGO-dZ: Map of elevation changes at 2 m and 20 m ground sampling distance. They are derived by co-registration and bias correction of the DSMs acquired about 5 years apart. Details of the corrections and of their accuracy are available in
Berthier & al., 2024[4].
More details at
https://www.legos.omp.eu/pgo/ 
