GFZ German research centre for geo sciences

E-GVAP: The EUMETNET EIG GNSS water vapour programme

Aside from main geodetic applications, GNSS has become an established atmospheric observing system for water vapour with high spatiotemporal resolution. In Europe, the application of GNSS in meteorology is a well-established field in both research and operation. Since 2005, E-GVAP (The EUMETNET EIG GNSS water vapour programme, is in charge of the collection and quality control of operational GNSS tropospheric products for numerical weather models (NWM). GFZ is one of the operational E-GVAP Analysis Centres (ACs) and processes with GFZ EPOS software more than 550 GNSS stations with a time delay better than 30 minutes after each hour (near real-time).

For monitoring purposes GNSS-derived tropospheric products are daily compared to the corresponding tropospheric parameters derived from a global numerical weather model, the Global Forecast System (GFS) of the National Centers for Environmental Prediction (NCEP) ( As a matter of example the following animation shows a one-to-one comparison of Zenith Wet Delays

The tropospheric products provided by GFZ are used by several European weather services like the Met Office, the United Kingdom's national weather service, and Météo-France, the French national meteorological service for their day-by-day forecasts.

Additionally GFZ provides as only one of the E-GVAP Analysis Centres the Slant Total Delays (STDs) with a time resolution of 2.5 minutes. At the same time, these specific data from up to 30 navigation satellites are currently used for studies to improve the precipitation forecast of the German Weather Service DWD.


Guerova, G., Jones, J., Douša, J., Dick, G., de Haan, S., Pottiaux, E., Bock, O., Pacione, R., Elgered, G., Vedel, H., Bender, M. (2016): Review of the state of the art and future prospects of the ground-based GNSS meteorology in Europe. - Atmospheric Measurement Techniques, 9, p. 5385-5406.

Schuh, H., Wickert, J., Dick, G., Ge, M., Ramatschi, M., Li, X., Deng, Z., Alshawaf, F., Arras, C., Männel, B. (2017): Der Beitrag von GNSS zum Monitoring des Systems Erde. - In: DVW – Gesellschaft für Geodäsie Geoinformation und Landmanagement e.V. , GNSS 2017 - Kompetenz für die Zukunft: Beiträge zum 157. DVW-Seminar am 21. und 22. Februar 2017 in Potsdam, (Schriftenreihe des DVW ; 87), Augsburg: Wißner Verlag, S. 43-54.

Lammert, A., Hansen, A., Ament, F., Crewell, S., Dick, G., Grützun, V., Klein-Baltink, H., Lehmann, V., Macke, A., Pospichal, B., Schubotz, W., Seifert, P., Stamnas, E., Stevens, B. (2019): A Standardized Atmospheric Measurement Data Archive for Distributed Cloud and Precipitation Process-Oriented Observations in Central Europe. - Bulletin of the American Meteorological Society, 100, 7, pp. 1299-1314, DOI:

back to top of main content