Can Galileo increase the accuracy and spatial resolution of the 3D tropospheric water vapour reconstruction by GPS tomography?

GPS tomography provides a unique opportunity to sense the 3D state of the atmosphere. However, the setting of the model grid can affect the water vapor solution since GPS data can be insufficient to cover all the domain, leading to an ill-posed conditioning, usually solved by constraints. In this work we present the result of a simulation analysis to study the impact of Galileo data on the reconstruction of 3D atmospheric water vapor. GPS tomography results are compared with those provided by merging GPS and Galileo data in order to ascertain the enhancement of the 3D water vapor refractivity reconstruction.