Developing a Novel Model to Estimate Zenith Hydrostatic Delay Using Surface Meteorological Data for GNSS-PWV Retrieval

• this study proposes a novel ZHD model (NZHD) that requires input of surface atmospheric pressure and water vapor pressure. • To address the challenge of obtaining real-time meteorological observations, we constructed a high-resolution grid model of atmospheric pressure and water vapor pressure for the Chinese region based on real-time meteorological observations. • Compared to traditional models such as SAAS and HGPT2, the NZHD model demonstrates improved accuracy, particularly in low-latitude