Water vapour distribution at urban scale using high-resolution numerical weather model and spaceborne SAR interferometric data
Ferretti Rossella(1), Pichelli Emanuela(1), Cimini Domenico(1), Perissin Daniele(2), Montopoli Mario(3), Marzano Frank S.(4) and Pierdicca Nazzareno(4)
(1) University of L'Aquila, Via Vetoio, 67010, Italy
(2) Polytechnic of Milan, P.le L. Da Vinci 32, 20133 Milan, Italy
(3) University of L'Aquila, Roio - L'Aquila, 67010, Italy
(4) Univ. of Rome 'La Sapienza', Via Eudossiana, 00184 Rome, Italy
The local distribution of water vapour in the urban area of Rome has been studied using both a high resolution mesoscale model (MM5) and ERS-1 (Earth Remote Sensing-1) satellite radar data. Interferometric Synthetic Aperture Radar (InSAR) techniques, after the removal of all other geometric effects, estimate excess path length variation between two different SAR acquisitions (Atmospheric Phase Screen: APS), which are strictly related to variations in the water vapour content along the radar line of sight. As a first step, both the high resolution integrated water vapour (IWV) from MM5 and InSAR APS maps have been compared with ECMWF data to establish the ability to reproduce gross features of the water vapour content spatial distribution. As a following step, the high resolution IWV model maps have been compared with InSAR data and the available data from surface meteorological stations. Several simulations were performed to set up the best configuration to run the MM5 model over the urban area. The results show that the high resolution IWV model maps well compare with the InSAR ones.