Ionospheric TEC spatial gradient observations and atmospheric pressure anomalies

<br>This dataset includes ionospheric TEC spatial gradient observations derived from GNSS stations during the Hunga Tonga-Hunga Ha'apai volcanic eruption on January 15, 2022 (see folders GIX and ROTI), as well as atmospheric pressure anomalies obtained from ground-based barometric pressure data (AWS). Additionally, we present the distribution of 3D PPP errors (3D PPP) from all the GNSS stations used during the period from 10:00 UTC to 15:00 UTC on January 15, 2022, and the time-series distribution of errors in the three components (E, N, U) for low-latitude GNSS stations (latitude &lt; 30°) (PPP) on that day.The original GNSS data can be requested from the Geospatial Information Authority of Japan (GSI) at the following website: https://www.gsi.go.jp/.The barometric pressure data are provided courtesy of Weathernews Inc. through their Soratena observation system. More information can be found here: https://global.weathernews.com/-innovation/soratena/.I would like to express my sincere gratitude to both organizations for providing the data. As the original data is openly accessible, this dissertation only presents the processed results. Due to limitations on the number of images that can be uploaded (figsize), only the final or necessary images have been included. If you require additional data or images, please feel free to contact me. Should you wish to use any of the images, I kindly ask that proper attribution be provided.