Incorporating Power-Law Model and ERA-5 Data for InSAR Tropospheric Delay Correction Analysis

Area of Science:

• Geodesy
• Remote Sensing
• Atmospheric Science

Background:

• Interferometric Synthetic Aperture Radar (InSAR) is crucial for monitoring urban subsidence and infrastructure stability.
• Atmospheric tropospheric delay is a major error source affecting InSAR accuracy.
• Highland basins present complex meteorological conditions and limited sounding balloon data.

Purpose of the Study:

• To develop and validate a novel method for correcting InSAR atmospheric phase delay using ERA-5 data within a power-law model.
• To address the challenge of insufficient sounding balloon data in complex regions for InSAR atmospheric correction.

Main Methods:

• The proposed Power-Law model with ERA-5 data (PLE5) replaces traditional sounding balloon data.
• ERA-5 reanalysis data was integrated into the power-law model for atmospheric delay correction.
• The PLE5 model's performance was evaluated in Dali using Sentinel-1 data and compared against GACOS, linear, and direct ERA-5 correction methods.

Main Results:

• The PLE5 model demonstrated the lowest phase standard deviation among the tested methods.
• This indicates a significant improvement in InSAR atmospheric delay correction accuracy.
• The study validated the effectiveness of the PLE5 model in a real-world scenario.

Conclusions:

• The PLE5 model offers a viable alternative for InSAR atmospheric correction in regions with sparse sounding balloon data.
• This method enhances the reliability and accuracy of InSAR-based deformation measurements.
• The findings contribute to more precise monitoring of urban subsidence and infrastructure stability.