Atmospheric effects represent one of the major limitations of repeat-pass interferometric synthetic aperture radar (InSAR). In this paper, GPS, and Moderate Resolution Imaging Spectroradiometer (MODIS) data were integrated to provide regional water vapor fields with a spatial resolution of 1 km ¿ 1 km, and a water vapor correction model based on the resultant water vapor fields was successfully incorporated into the Jet Propulsion Laboratory/California Institute of Technology ROI_PAC software. The advantage of this integration approach is that only one continuous GPS station is required within a 2030 km ¿ 1354 km MODIS scene. Application to ERS-2 repeat-pass data over the Los Angeles Southern California Integrated GPS Network (SCIGN) area shows that this integration approach not only helps discriminate geophysical signals from atmospheric artifacts but also reduces water vapor effects significantly, which is of great interest to a wide community of geophysicists.