An absolute measurements campaign were performed in July and august 2022 on the reference sites of Brest (Shom), of La Rochelle and of Aix Island.

With the support of the SNO (Service National d’Observation) gravimetry, these measurements allow to check the long-term vertical stability of tide gauges

This campaign was funded by the ROYMAGE ANR and has been done with the FG5-228 gravimeter operated by the Montpellier University