Benefits for the Atmospheric Remote Sensing by Integrating GPS and GALILEO Systems
Vespe, F.
Agenzia Spaziale Italiana

The work has the objective to demonstrate as the future GALILEO will improve dramatically the performances of the current Global Navigation Satellite Systems in the field of the atmospheric remote sensing. In particular we plan to demonstrate the not negligible benefits the Earth radio occultation techniques will enjoys by using a doubled constellation of GNSS satellites in terms of number of occurring events. The doubling of the number of occultations will make more feasible the set up of a numerical weather predictions service based on global scale and a more precise and relevant monitoring of Climate Global Change. Furthermore It will be demonstrated how the increasing number of GNSS radio occultation events will make more feasible the calibration of Nadir pointing satellite payloads devoted to climate monitoring like the Fourier spectrometer. On the other hand with the present work we try to prove that the tremendous improvement of the gravity field models could make feasibile the use of precise orbit determination of Earth satellites as a tool for sensing a global changes of some key atmosphere parameters like refractivity and extinction. The huge number of running Earth’s satellites and combinations of their orbital parameters (namely the nodes) in a gravity field free fashion (GF-free) can magnify the solar radiation pressure acting on MEO satellites ( GPS, Etalon and, in near real future GALILEO) and its smooth modulation through the Earth’s atmosphere (penumbra). We would remind that The GF-free technique is able to cancel out with n satellite orbital parameters the first n-1 even zonal harmonics of the gravity field.