Ray-traced Troposphere Slant Delays from Numericalweather Models as Corrections for Insar

Highly variable weather conditions, especially the rapidly changing water vapor distribution, bias the interpretation of interferometric synthetic aperture radar (InSAR) images. Any change of atmospheric condition is reflected as differential propagation delay in the InSAR images, which is difficult to distinguish from the real ground motion. Moreover, for areas which cover a wide range of altitudes the proper treatment of the hydrostatic delay component becomes important, too. In the past there have been several studies using numerical weather models for compensation of such effects [1]. Founded on these investigations, we have developed an advanced troposphere delay mitigation algorithm, based on the computation of ray-traced delays for each InSAR pixel using 4D fine-mesh numerical weather models.