Reducing Atmospheric Water Vapor Effects on the Interferogrametric SAR Products using MERIS-FR and GPS (Case Study: Mashhad subsidence)

SAR interferometry has shown its abilities in measuring the surface deformation in various applications. Atmospheric signals as an important factor affecting the interferometric measurements have temporally uncorrelated and complicated behavior. In this paper, a model based on the error source is presented to reduce the atmospheric contributions on the interferometric measurements in Mashhad subsidence area. In this model, the Full-Resolution (RF) MODIS data and meteorological information were used in order to estimate the water vapor and reduce the pressure effect, respectively. Moreover, water drops as well as the clouds effects were considered in the proposed model. Utilizing error propagation, model error was estimated as 7.2 mm. The Root Mean Square Error (RMSE) as a quantitative comparison between GPS measurements and interferometric results showed an improvement from 9 mm (before atmospheric correction) to 2 mm after applying the correction model.