Status: this preprint was under review for the journal AMT but the revision was not accepted.
Establishment of a regional precipitable water vapor model based on the combination of GNSS and ECMWF data
Yibin Yao,Xingyu Xu,and Yufeng Hu
Abstract. Water vapor is the engine of the weather. Owing to its large latent energy, the phase changes of water vapor significantly affect the vertical stability, structure and energy balance of the atmosphere. Many techniques are used for measuring the water vapor in the atmosphere such as radiosondes, Global Navigation Satellite System (GNSS) and water vapor radiometer (WVR). In addition, the method that uses European Centre for Medium-range Weather Forecasts (ECMWF) data is an important method for studying the variations in precipitable water vapor (PWV). This paper used both GNSS PWV and ECMWF PWV to establish a city-level local PWV fusion model using a Gaussian Processes method. The results indicate that by integrating the precipitable water vapor obtained from GNSS and ECMWF data, the accuracy of fusion PWV is improved by 1.89 mm in active tropospheric conditions and 2.61 mm in quiescent tropospheric conditions compared with ECMWF-PWV, reaching 3.87 mm and 3.97 mm, respectively. Furthermore, the proposed fusion model is used to study the spatial and temporal distribution of PWV in Hong Kong. It is found that the accumulation of PWV corresponds to monsoon and rainfall events.
Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this paper. While Copernicus Publications makes every effort to include appropriate place names, the final responsibility lies with the authors. Views expressed in the text are those of the authors and do not necessarily reflect the views of the publisher.