Study of tropospheric delay over Indian region from MODIS, NCEP/NCAR data and ground based water vapor measurements at Kolkata

•Tropospheric delay is critical in navigation, VLBI and InSAR data processing.•It is modeled over Indian region using MODIS observation and meteorological data.•Wet delay is found to have significant seasonal variability.•Variation of tropospheric delay is most prominent in the Indo-Gangetic plain.