High resolution numerical weather models have recently raised a great interest in the InSAR community for atmospheric phase screen (APS) mitigation. Following the research carried out in [1], in this study we focus on investigating the sensitivity of WRF (Weather Research and Forecasting) predictions to the model parameter settings which may substantially affect the result of water vapor modeling and to different boundary conditions. We validate the model predictions using atmosphere-only interferograms as well as radiosonde records. Our result shows that the radiosonde records (on average) agree very well with the WRF predictions based on our new model settings. However, in terms of spatio-temporal delay variation, the new settings do not always lead to a better prediction and the correction of atmospheric delay is case dependent. Therefore, we conclude that WRF lacks the reliability to correct the realistic APS in interferograms.@en

Atmospheric delay is one of the major error sources in In-SAR, hindering the accurate monitoring of ground motion. Here we use the WRF (Weather Research and Forecasting) weather model to hindcast atmospheric delays at SAR acquisition times over both mountainous and flat regions. The performance of the model is evaluated by comparing it to interferograms formed using acquisitions with short temporal baselines (≤4 months). Our results show that for flat regions the model not only misestimates atmospheric delay in magnitude and location but also largely underestimates the (horizontal) spatial variation (turbulent mixing) of the delay. In mountainous areas it can model the height dependent (vertical stratification) part of total delay correctly in some cases but not always. By removing the height dependent part we find again that the model may underestimate the spatial variation of the delay. Therefore, we conclude that the WRF weather model is in general not reliable for the operational mitigation of atmospheric delay in interferograms. ©2009 IEEE.
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