Integrating tropospheric parameters from different observing techniques

Co-location of independent space geodetic and remote sensing techniques allows to combine and integrate the independently derived results for tropospheric parameters. The combined results promise to provide a robust and consistent basis for possible applications in climate related research and may give complementary information to the results derived from traditional meteorological techniques. For our study we use the independent and co-located techniques of geodetic VLBI, GPS and microwave radiometry at the Onsala Space Observatory and aditionally radiosonde observations taken at the Landvetter airport in 38 km distance. We combine and integrate the atmospheric water vapor content that is derived from the different techniques on time scales up to more than two decades. We apply different statistical approaches and investigate for possible trends in the amount of atmospheric water vapor. The derived results are compared to a climate model.