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Tropospheric correction techniques in repeat-pass SAR interferometry (2003)
| Content Provider | CiteSeerX |
|---|---|
| Author | Li, Zhenhong Muller, Jan-Peter Cross, Paul |
| Description | [Abstract] For the first time, the application of a spaceborne near infrared (IR) water vapour product from the NASA Moderate Resolution Imaging Spectroradiometer (MODIS) for reducing water vapour effects of ERS-2 measurements are presented. The MODIS near IR water vapour product has been available since the end of February 2000 with a spatial resolution of 1km (at nadir) and a moderate accuracy of 5-10%. Coincident data with ERS-2 used in this study were located over Mt. Etna and Southern California. The results showed that the MODIS near IR water vapour product could be useful in reducing atmospheric effects in ERS-2 SAR interferometric data. Taking these results into account and the fact that, the MEdium Resolution Imaging Spectrometer (MERIS) has a higher accuracy and is on board the same platform, ENVISAT, as the Advanced Synthetic Aperture Radar (ASAR), future prospects look optimistic. The major limitation for either MODIS or MERIS is the reliance on cloud-free water vapour retrievals with the percentage of cloud free observations as low as 25%. In this paper, also for the first time, 3D GPS water vapour (or wet refractivity) models were applied to correct ERS-2 SAR interferometric data. Firstly, the WAter Vapour Extraction Software (WAVEs), developed at UCL, was used to construct a 3D water vapour (or wet refractivity) model with an appropriate resolution making full use of the spatial structure of zenith wet delays; then the difference in LOS (Line-of-Sight) path delays were calculated and applied to correct InSAR measurements. The results showed that the volumetric fields derived using the 3D GPS water vapour model can reduce water vapour effects significantly. It also showed that such 3D models are sensitive to the distribution of GPS receivers. Presently, a new way to fuse MODIS or MERIS with ground-based GPS networks within the WAVEs package is under investigation at UCL. 1. |
| File Format | |
| Language | English |
| Publisher Date | 2003-01-01 |
| Publisher Institution | In: Proceeding of FRINGE 2003 Workshop, ESA ESRIN |
| Access Restriction | Open |
| Subject Keyword | Coincident Data First Time Ir Water Vapour Product Volumetric Field Zenith Wet Delay Advanced Synthetic Aperture Radar Water Vapour Product Ers-2 Measurement Ground-based Gps Network Water Vapour Appropriate Resolution Water Vapour Effect Insar Measurement Gps Water Vapour Spatial Structure Atmospheric Effect Cloud Free Observation Cloud-free Water Vapour Retrieval Moderate Accuracy Gps Receiver Major Limitation Ers-2 Sar Interferometric Data Future Prospect Full Use Nasa Moderate Resolution Imaging Spectroradiometer Spatial Resolution Gps Water Vapour Model Southern California Path Delay New Way Tropospheric Correction Technique Medium Resolution Imaging Spectrometer Wave Package Repeat-pass Sar Interferometry Water Vapour Extraction Software |
| Content Type | Text |
| Resource Type | Article |
