A Comparative Analysis of Tropospheric Water Vapor Measurements from MERIS and SAR

Tropospheric water vapor delay is the main error source limiting the accuracy of SAR interferometric measurements. In persistent scatterer interferometry (PSI), the presence of atmospheric effects increases the required data amount for PSI immensely, limiting the reaction time and applicability of the technique. On ENVISAT, water vapor products derived from the optical sensor MERIS may be used to mitigate tropospheric effects in simultaneously acquired ASAR data. In this paper the atmospheric signals in MERIS and ASAR are compared, and methods for their optimal combination are suggested.