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Although the atmospheric compensation models developed to date have been generally robust and effective for InSAR, how to choose the right atmospheric correction method for ground-based InSAR is wo...

Atmospheric phase screen (APS) is one of the main error sources of interferometric synthetic aperture radar (InSAR) measurements. In order to accurately retrieve displacement fields, it is necessary to use advanced methods to eliminate the tropospheric effect of interferograms. In this paper, the land subsidence in Kurdistan province of Iran is investigated using Sentinel-1A acquisitions on a single track for the period 2014–2018. The accurate and applicable 3D ray tracing technique is used to accurately estimate the APS. The ERA-I reanalysis data generated by European Centre for Medium Range Weather Forecasts (ECMWF) are used to implement the 3D ray tracing technique. In order to determine the effect of using the 3D ray tracing technique, the APSs are also determined using a traditional approach called, spatiotemporal filters method. To evaluate the capability of the two methods, the results are compared with the weather research and forecasting model (WRF) model. Finally, the interferograms are corrected using APSs from 3D ray tracing technique and traditional method and the subsidence rate in the study area is computed. Comparing the subsidence rates obtained from two APS estimation methods with piezometric data, GPS and precise levelling observations shows that the 3D ray tracing technique is significantly more accurate than traditional method in computing InSAR displacement fields.

Boundary and area information could be used to study various interesting relations of multiple disasters such as "magnitude-area" relation for earthquakes. In this paper, a new method using InSAR-derived interferograms to determine the boundary of the crustal deformation area is introduced. Although InSAR has been widely used in crustal deformation monitoring, little is known about boundary detection using interferograms. The proposed method conducted Atmospheric Phase Screen (APS) correction to the interferograms based on Numerical Weather Prediction (NWP) model offered by Generic Atmospheric Correction Online Service for InSAR (GACOS). Moreover, this study proposed a suggestion to identify points in the interferograms at which the deformation changes smoothly that could be determined as the far-field boundary. Here we used a pair of Sentinel-1A images to investigate the deformation boundary associated with the 2017 Iran Sangsefid earthquake as an example. It was experimentally shown that the proposed method provided an inspiring scheme for boundary detection based on InSAR interferograms.

Based on ALOS PALSAR images, time series deformation fields of the Agung volcano area were obtained using SBAS-InSAR in 2007–2009. The time series deformation showed obvious inflation around the Agung volcano area, which was positively correlated with time. We modeled the cumulated deformation interferogram based on Mogi point source and vertical prolate spheroid source. The deformation model indicated that the vertical prolate spheroid model fit the observed deformation reasonably well. The magma chamber was located beneath the center of the volcano at a depth of approximately 5 km beneath the summit.

SAR interferometry has long been regarded as an effective tool for wide-area topographic mapping in hilly and mountainous areas. However, quality of InSAR DEM product is usually affected by atmospheric disturbances and decorrelation-induced voids, especially for data acquired in repeat-pass mode. In this paper, we proposed an approach for improved topographic mapping by optimal fusion of multi-orbit InSAR DEMs with correction of atmospheric phase screen (APS). An experimental study with high-resolution TerraSAR-X and COSMO-SkyMed datasets covering a mountainous area was carried out to demonstrate the effectiveness of the proposed approach. Validation with a reference DEM of scale 1:50,000 indicated that vertical accuracy of the fused DEM can be better than 5 m.

The PSInSAR technique, invented by Ferretti et. al. [1], [2], [3] ten years ago, meanwhile has proven it's capability for very precise measurement of surface deformations. To achieve this, the influence of the atmospheric phase screen (APS) has to be removed. We investigated the APS for two series of TerraSAR-X high resolution spotlight data of a scene in Bavaria. Our approach was to consider the APS as composed of a phase ramp, a part stratified with height and a turbulent component. We estimated the turbulent component via kriging. The variograms show for short distances a regime which is not visible for lower resolutions. In this paper we discuss the choice of appropriate variogram models with respect to our data.

To overcome the shortage of conventional least squares (LS) DInSAR technique which can only obtain the optimal deformation under ideal condition, we propose an advanced LS algorithm to retrieve ground deformation over large areas. In this algorithm, two extensions are derived. First, the atmospheric phase screen (APS) is removed from the differential interferometric phases by temporal low-pass filtering. Second, topographic errors are considered in the linear model to be separated from deformation. The proposed algorithm has been tested with an ALOS PALSAR data set relative to southern Jiangsu Province, covering the cities of Suzhou and Wuxi, East China. Finally, leveling data validate the results.