GNSS Integrated Water Vapour data over France and Europe, for EURO- and Med-CORDEX.

This data set contains 6-hourly, daily and monthly Integrated Water Vapour (IWV) data from the French Permanent GNSS network (RGP), as well as a few european and worldwide stations, for the period 2000-2009, in support to EURO- and Med-CORDEX project. The raw GNSS data were processed by Institut National de l’Information Geographique et Forestiere (IGN), France, with Bernese GNSS software v5.0, and ZTD estimates were converted into IWV by Institut de Physique du Globe de Paris (IPGP). Processing options were: GPS observations only with 3 min sampling, processing window of 24 hours, satellite ephemerids and clocks, ERPs, and antenna models were from IGS repro1 (http://acc.igs.org/reprocess.html), all other models and products followed the IERS2010 conventions. Station coordinates were estimated as one constant per day with loose constraints, while ZTDs and tropospheric gradient parameters, were estimated as piece-wise linear functions of time, with a sampling of 1 hour for ZTD and 24 hours for gradients, both with loose constraints. The ZTD estimates were screened for outliers (values with formal error > 1 cm were rejected) and converted to IWV (using ERA5 6-hourly pressure level data with bi-linear horizontal interpolation from the four surrounding grid points). Daily IWV values were computed as weighted means of 00, 06, 12, 18 UTC of the day and 00 UTC of the next day. Monthly IWV values were computed from the 6-hourly data with a minimum of 60 values per month. More information about the post-processing can be found in Bock and Parracho (2019).