[A-CG41] Satellite Earth Environment Observation

[ACG41-P15] Ship-borne GNSS-derived Precipitable water vapor in the Northwest Pacific in summer

*Dong-Hyo Sohn¹, Byung-Kyu Choi¹, Yosup Park², Byung-Il Lee³ (1.Korea Astronomy and Space Science Institute, 2.Korea Institute of Ocean Science and Technology, 3.National Meteorological Satellite Center)

Keywords:GNSS, Precise Point Positioning, shipborne, precipitable water vapor

In this work, we estimate global navigation satellite system (GNSS) precipitable water vapor (PWV) using multi-GNSS measurements obtained from the research vessel in the Northwest Pacific in summer. Many studies have demonstrated that ground-based static GNSS-derived PWV has reached a few millimeters of accuracy. However, GNSS observations performed in the ocean are relatively rare, making PWV observations at sea difficult to achieve. We study to derive the multi-GNSS PWV using the kinematic precise point positioning (PPP) solution developed by the Korea Astronomy and Space Science Institute. The experiment was carried out from July 30, 2021, to August 25, 2021, in the Northwest Pacific on board the ISABU, a research vessel (R/V) weighing approximately 6,000 tons operated by the Korea Institute of Ocean Science and Technology. The ship-borne GNSS PWV was compared with the results observed by radiosondes operated by ships and KOMSAT-2A, a meteorological observation satellite in geostationary orbit. The retrieving GNSS PWV in the ship-based dynamic environment showed an error accuracy of several mm and a bias of less than 1 mm with the two observation systems. Although it showed a relatively large error compared to the study case using the data observed at the land-based fixed reference station, a reasonable level of results was obtained.