Articles | Volume 15, issue 5
https://doi.org/10.5194/gmd-15-2293-2022
© Author(s) 2022. 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-15-2293-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Development and technical paper
| 
17 Mar 2022
Development and technical paper |
| 17 Mar 2022
| 17 Mar 2022
An update on the 4D-LETKF data assimilation system for the whole neutral atmosphere
Department of Earth Planetary Science, The University of Tokyo,
Tokyo, 1130033, Japan
Kaoru Sato
Department of Earth Planetary Science, The University of Tokyo,
Tokyo, 1130033, Japan
Masashi Kohma
Department of Earth Planetary Science, The University of Tokyo,
Tokyo, 1130033, Japan
Shingo Watanabe
Japan Agency for Marine-Earth Science and Technology, Yokohama,
2360001, Japan
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Short summary
The 4D ensemble Kalman filter data assimilation system for the whole neutral atmosphere has been updated. The update includes the introduction of a filter to reduce the generation of spurious waves, change in the order of horizontal diffusion of the forecast model to reproduce more realistic tidal amplitudes, and use of additional satellite observations. As a result, the analysis performance has been greatly improved, even for disturbances with periods of less than 1 d.
The 4D ensemble Kalman filter data assimilation system for the whole neutral atmosphere has been...
