An Overview of COST Action 716: Exploitation of Ground-Based GPS for
Climate and Numerical Weather Prediction Analysis.

Gunnar Elgered
Onsala Space Observatory
Chalmers University of Technology
S-43992 Onsala, Sweden

Up to now GPS measurements of atmospheric water vapour have been used, as
an independent observational data set, to validate results from Numerical
Weather Prediction (NWP) models applied to forecasting activities and
climate research. Within the COST action we aim at the operational
applications as well as identifying the needs for requirements on a high
quality GPS data set for climate studies.
The primary objective is the assessment of the operational potential on
an international scale of the exploitation of a ground-based GPS system to
provide near real time observations for numerical weather prediction and
climate applications.

The COST action had its first Management Committee was held in Brussels
on January 8, 1999. The following 14 countries participate in the action:
Austria, Belgium, Denmark, Finland, France, Germany, Hungary, Italy,
Netherlands, Norway, Spain, Sweden, Switzerland, and United Kingdom.

The action is divided into four projects, each run by a working group:

(1) State of the art and product requirement, all participating countries
have reviewed their status and a final document is planned to be
distributed during the summer of 2000.

(2) A demonstration project, where a near real-time campaign will be
carried out early 2001, including all the steps from data acquisition to
assimilation into an NWP model.

(3) Applications, which includes the specifications from the
meteorology and climate communities. Here we stress the importance of
recognizing the different requirements of the GPS results depending on
the usage of the data.

(4) Planning for the operational phase. This project has not yet
commenced.

More information can be obtained at the home page of the action:
http://www.oso.chalmers.se/geo/cost716.html