RIKEN Center for Computational Science Data Assimilation Research Team
Team Principal: Takemasa Miyoshi (Ph.D.)
Research Summary

Data assimilation (DA) is a cross-disciplinary science to synergize computer simulations and real-world data, using statistical methods and applied mathematics. As computers become more powerful and enable more precise simulations, it will become more important to compare the simulations with actual observations. DA Team performs cutting-edge research and development on advanced DA methods and their wide applications, aiming to integrate computer simulations and real-world data in the wisest way. Particularly, DA Team tackles challenging problems of developing efficient and accurate DA systems for “big simulations” with real-world “big data” from various sources including advanced sensors. The specific foci include 1) theoretical and algorithmic developments for efficient and accurate DA, 2) DA methods and applications by taking advantage of the world-leading supercomputer and “big data” from new advanced sensors, and 3) exploratory new applications of DA in wider simulation fields. These advanced DA studies will enhance simulation capabilities and lead to a better use of high-performance computers.
Main Research Fields
- Mathematical & Physical Sciences
Related Research Fields
- Informatics
Keywords
- Data Assimilation
- Numerical Weather Prediction
- Large Scale Simulation
- Ensemble Data Assimilation
- Natural disaster prediction
Research Subjects
- Ensemble-based data assimilation suitable to various high-dimensional simulations
- Theoretical research on challenging problems in data assimilation
- Wide applications of data assimilation
- Cutting-edge data assimilation research on geophysical applications
- Data assimilation using Big Data
Selected Publications
- 1.
Liang, J., N. Sugimoto, and T. Miyoshi,
"2025: Unveiling Energy Conversions of the Venus Atmosphere by the Bred Vectors. Geophysical Research Letters, 52, e2024GL112663."
doi:10.1029/2024GL1126631 - 2.
Ohishi, S., T. Miyoshi, T. Ando, T. Higashiuwatoko, E. Yoshizawa, H. Murakami, and M. Kachi,
"2024: LETKF-based Ocean Research Analysis (LORA) version 1.0, Geoscience Data Journal, 11, 995-1006."
doi:10.1002/gdj3.2711 - 3.
Li, L., J. Li, and T. Miyoshi,
"2024: Chaos suppression through Chaos enhancement, Nonlinear Dyn.",
doi:10.1007/s11071-024-10426-z1 - 4.
Sun, Q., T. Miyoshi, S. Richard,
"2023: Analysis of COVID-19 in Japan with extended SEIR model and ensemble Kalman filter., Journal of Computational and Applied Mathematics."
doi.org/10.1016/j.cam.2022.1147721 - 5.
Miyoshi, T., A. Amemiya, S. Otsuka, Y. Maejima, J. Taylor, T. Honda, H. Tomita, S. Nishizawa, K. Sueki, T. Yamaura, Y. Ishikawa, S. Satoh, T. Ushio, K. Koike, and A. Uno,
"2023: Big Data Assimilation: Real-time 30-second-refresh Heavy Rain Forecast Using Fugaku During Tokyo Olympics and Paralympics. In Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis (SC '23). Association for Computing Machinery, 8, 1-10."
doi:10.1145/3581784.36270471 - 6.
Miyoshi, T. and Sun, Q.,
"2022: Control Simulation Experiment with the Lorenz's Butterfly Attractor, Nonlin. Processes Geophys., 29, 133-139, 2022."
doi.org/10.5194/npg-29-133-20221 - 7.
Honda, T., S. Kotsuki, G.-Y. Lien, Y. Maejima, K. Okamoto and T. Miyoshi,
"2018: Assimilation of Himawari-8 All-Sky Radiances Every 10 Minutes: Impact on Precipitation and Flood Risk Prediction. J. Geophys. Res., 123, 965-976."
doi:10.1002/2017JD0270961 - 8.
Miyoshi, T., G.-Y. Lien, S. Satoh, T. Ushio, K. Bessho, H. Tomita, S. Nishizawa, R. Yoshida, S. A. Adachi, J. Liao, B. Gerofi, Y. Ishikawa, M. Kunii, J. Ruiz, Y. Maejima, S. Otsuka, M. Otsuka, K. Okamoto, and H. Seko,
"2016: "Big Data Assimilation" toward Post-peta-scale Severe Weather Prediction: An Overview and Progress. Proc. of the IEEE, 104, 2155-2179."
doi:10.1109/JPROC.2016.26025601 - 9.
Miyoshi, T., M. Kunii, J. Ruiz, G.-Y. Lien, S. Satoh, T. Ushio, K. Bessho, H. Seko, H. Tomita, and Y. Ishikawa,
"2016: "Big Data Assimilation" Revolutionizing Severe Weather Prediction. Bull. Amer. Meteor." Soc., 97, 1347-1354."
doi:10.1175/BAMS-D-15-00144.1 - 10.
Miyoshi, T., K. Kondo, and T. Imamura,
"2014: The 10240-member ensemble Kalman filtering with an intermediate AGCM. Geophys. Res. Lett., 41, 5264-5271."
doi:10.1002/2014GL060863
Recent Research Results
Dec. 26, 2023
Turning the tables on weather forecastingJun. 22, 2023
Scientists show way to mitigate extreme weather eventsMar. 28, 2022
Chaos theory provides hints for controlling the weather
Related Links
- Data Assimilation Research Team | RIKEN Center for Computational Science
- Data Assimilation Research Team's website
- Prediction Science Research Team | RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences
- YouTube RIKEN Channel "Predicting sudden downpours"
- Release of JAXA-RIKEN Ocean Analysis through JAXA’s P-Tree System (Apr 24, 2023) | RIKEN Center for Computational Science
- Aug. 20, 2020 News "RIKEN and JAXA collaborate to offer real-time rainfall forecasts"
Lab Members
Principal investigator
- Takemasa Miyoshi
- Team Principal
Core members
- Shigenori Otsuka
- Senior Research Scientist
- James Taylor
- Research Scientist
- Michael Robert Goodliff
- Research Scientist
- Shun Ohishi
- Research Scientist
- Tristan Hascoet
- Research Scientist
- Arata Amemiya
- Research Scientist
- Jianyu Liang
- Postdoctoral Researcher
- Yuta Tarumi
- Postdoctoral Researcher
- Tatsuro Iwanaka
- Research Associate
- Shungo Tonoyama
- Research Associate
- Takahisa Ishimizu
- Technical Staff I
- Shu-Chih Yang
- Senior Visiting Scientist
- John Craig Wells
- Senior Visiting Scientist
- Juan Ruiz
- Visiting Scientist
- Koji Terasaki
- Visiting Scientist
- Shunji Kotsuki
- Visiting Scientist
Contact Information
7-1-26,Minatojima-minami-machi,
Chuo-ku,Kobe,Hyogo
650-0047,Japan
Email: da-team-desk@ml.riken.jp