Articles | Volume 18, issue 16
https://doi.org/10.5194/gmd-18-5015-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-18-5015-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Model description paper
| 
18 Aug 2025
Model description paper |
| 18 Aug 2025
| 18 Aug 2025
Least travel time ray tracer version 2 (LTT v2) adapted to the grid geometry of the OpenIFS atmospheric model
Maksym Vasiuta
CORRESPONDING AUTHOR
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Angel Navarro Trastoy
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Sanam Motlaghzadeh
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Lauri Tuppi
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Torsten Mayer-Gürr
Institute of Geodesy, Graz University of Technology, Graz, Austria
Heikki Järvinen
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
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Short summary
Propagation of electromagnetic signals in Earth's neutral atmosphere inflicts errors in space geodetic observations. To model these errors accurately, it is necessary to use a signal tracing algorithm which is informed of the state of the atmosphere. We developed such an algorithm and tested it by processing Global Navigation Satellite System network observations. Our algorithm's main advantage is lossless utilization of atmospheric information provided by numerical weather prediction models.
Propagation of electromagnetic signals in Earth's neutral atmosphere inflicts errors in space...
