6444 20230420105530.0 POSTER-2023-0038 Morel, L Global validity and behaviour of tropospheric gradients estimated by GPS 2018 2018-04-12 STCE Pottiaux, E. Durand, F. Follin, J.-M. Durand, S. Van Baelen, J. European Geosciences Union General Assembly 2018, Vienna, Austria eric.pottiaux@observatoire.be CPOSTER