Articles | Volume 33, issue 1
https://doi.org/10.5194/npg-33-33-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/npg-33-33-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Localization in the mapping particle filter
Juan M. Guerrieri
CORRESPONDING AUTHOR
Departamento de Física, FaCENA, Universidad Nacional del Nordeste, Corrientes, Argentina
Departamento de Ciencias de la Atmósfera y los Océanos, FCEyN, Universidad de Buenos Aires, Buenos Aires, Argentina
IMIT, CONICET, Corrientes, Argentina
Manuel Pulido
Departamento de Física, FaCENA, Universidad Nacional del Nordeste, Corrientes, Argentina
IMIT, CONICET, Corrientes, Argentina
Takemasa Miyoshi
RIKEN Center for Computational Science, Kobe, Japan
RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences, Kobe, Japan
Arata Amemiya
Japan Weather Association, Tokyo, Japan
Juan J. Ruiz
Departamento de Ciencias de la Atmósfera y los Océanos, FCEyN, Universidad de Buenos Aires, Buenos Aires, Argentina
Centro de Investigaciones del Mar y la Atmósfera, CIMA/CONICET-UBA, Buenos Aires, Argentina
Instituto Franco-Argentino para el Estudio del Clima y sus Impactos (IRL IFAECI/CNRS-IRD-CONICET-UBA), Buenos Aires, Argentina
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Yuki Kobayashi, Shun Ohishi, and Takemasa Miyoshi
EGUsphere, https://doi.org/10.5194/egusphere-2026-2653, https://doi.org/10.5194/egusphere-2026-2653, 2026
This preprint is open for discussion and under review for Nonlinear Processes in Geophysics (NPG).
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Modern environmental forecasting combines computer simulations with real-world observations. Most systems assume errors in these sources are independent, but in reality, they are occasionally linked. We developed a new method to estimate the hidden correlations. Using a simplified atmospheric model, we showed our method successfully identifies the correlations and significantly improves prediction accuracy. This work provides a practical path toward more reliable weather and ocean forecasts.
Shun Ohishi, Takemasa Miyoshi, and Misako Kachi
EGUsphere, https://doi.org/10.5194/egusphere-2026-2277, https://doi.org/10.5194/egusphere-2026-2277, 2026
This preprint is open for discussion and under review for Ocean Science (OS).
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We developed a new eddy-permitting local ensemble Kalman filter (LETKF)-based Ocean Research Analysis (LORA) version 2.0 for a quasi-global domain (LORA-QG) from June 2002. Validation results show that LORA-QG is the second-most accurate among the four quasi-global and global ocean analysis datasets and has sufficient accuracy for scientific and practical applications.
Arata Amemiya and Takemasa Miyoshi
Nonlin. Processes Geophys., 33, 1–16, https://doi.org/10.5194/npg-33-1-2026, https://doi.org/10.5194/npg-33-1-2026, 2026
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The accurate estimation of atmospheric state variables from radar observation in rapidly growing deep convection, which causes heavy thunderstorms, is a major challenge. This study examines the advantage of incorporating radar observation data with very high frequency such as 30 s compared with the conventional case of 5 min, from a theoretical perspective.
Kota Takeda and Takemasa Miyoshi
EGUsphere, https://doi.org/10.5194/egusphere-2025-5144, https://doi.org/10.5194/egusphere-2025-5144, 2025
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This study examines how small an ensemble can be while maintaining long-term accuracy in an ensemble forecasting method, which is widely used for predicting complex systems such as the atmosphere and ocean. Using a chaotic model, we show that the minimum ensemble size required for accurate forecasts is related to the system's degree of instability. We also propose an efficient downsizing method that ensures stable and accurate performance with lower computational cost.
Michael Goodliff and Takemasa Miyoshi
EGUsphere, https://doi.org/10.5194/egusphere-2025-933, https://doi.org/10.5194/egusphere-2025-933, 2025
Preprint archived
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Data-driven models (DDMs) learn from large datasets to make predictions, but data limitations affect reliability. Data assimilation (DA) improves accuracy by combining real-world observations with computational models. This research explores how DA enhances DDMs despite limited data. We propose an algorithm using DA to refine DDM training iteratively. This work has broad implications for fields like meteorology, engineering, and environmental science, where accurate prediction is critical.
Pierre Le Bras, Florian Sévellec, Pierre Tandeo, Juan Ruiz, and Pierre Ailliot
Nonlin. Processes Geophys., 31, 303–317, https://doi.org/10.5194/npg-31-303-2024, https://doi.org/10.5194/npg-31-303-2024, 2024
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The goal of this paper is to weight several dynamic models in order to improve the representativeness of a system. It is illustrated using a set of versions of an idealized model describing the Atlantic Meridional Overturning Circulation. The low-cost method is based on data-driven forecasts. It enables model performance to be evaluated on their dynamics. Taking into account both model performance and codependency, the derived weights outperform benchmarks in reconstructing a model distribution.
Kenta Kurosawa, Shunji Kotsuki, and Takemasa Miyoshi
Nonlin. Processes Geophys., 30, 457–479, https://doi.org/10.5194/npg-30-457-2023, https://doi.org/10.5194/npg-30-457-2023, 2023
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This study aimed to enhance weather and hydrological forecasts by integrating soil moisture data into a global weather model. By assimilating atmospheric observations and soil moisture data, the accuracy of forecasts was improved, and certain biases were reduced. The method was found to be particularly beneficial in areas like the Sahel and equatorial Africa, where precipitation patterns vary seasonally. This new approach has the potential to improve the precision of weather predictions.
Qiwen Sun, Takemasa Miyoshi, and Serge Richard
Nonlin. Processes Geophys., 30, 117–128, https://doi.org/10.5194/npg-30-117-2023, https://doi.org/10.5194/npg-30-117-2023, 2023
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This paper is a follow-up of a work by Miyoshi and Sun which was published in NPG Letters in 2022. The control simulation experiment is applied to the Lorenz-96 model for avoiding extreme events. The results show that extreme events of this partially and imperfectly observed chaotic system can be avoided by applying pre-designed small perturbations. These investigations may be extended to more realistic numerical weather prediction models.
Tobias Necker, David Hinger, Philipp Johannes Griewank, Takemasa Miyoshi, and Martin Weissmann
Nonlin. Processes Geophys., 30, 13–29, https://doi.org/10.5194/npg-30-13-2023, https://doi.org/10.5194/npg-30-13-2023, 2023
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This study investigates vertical localization based on a convection-permitting 1000-member ensemble simulation. We derive an empirical optimal localization (EOL) that minimizes sampling error in 40-member sub-sample correlations assuming 1000-member correlations as truth. The results will provide guidance for localization in convective-scale ensemble data assimilation systems.
Shun Ohishi, Takemasa Miyoshi, and Misako Kachi
Geosci. Model Dev., 15, 9057–9073, https://doi.org/10.5194/gmd-15-9057-2022, https://doi.org/10.5194/gmd-15-9057-2022, 2022
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An adaptive observation error inflation (AOEI) method was proposed for atmospheric data assimilation to mitigate erroneous analysis updates caused by large observation-minus-forecast differences for satellite brightness temperature around clear- and cloudy-sky boundaries. This study implemented the AOEI with an ocean data assimilation system, leading to an improvement of analysis accuracy and dynamical balance around the frontal regions with large meridional temperature differences.
Shun Ohishi, Tsutomu Hihara, Hidenori Aiki, Joji Ishizaka, Yasumasa Miyazawa, Misako Kachi, and Takemasa Miyoshi
Geosci. Model Dev., 15, 8395–8410, https://doi.org/10.5194/gmd-15-8395-2022, https://doi.org/10.5194/gmd-15-8395-2022, 2022
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We develop an ensemble-Kalman-filter-based regional ocean data assimilation system in which satellite and in situ observations are assimilated at a daily frequency. We find the best setting for dynamical balance and accuracy based on sensitivity experiments focused on how to inflate the ensemble spread and how to apply the analysis update to the model evolution. This study has a broader impact on more general data assimilation systems in which the initial shocks are a significant issue.
Shunji Kotsuki, Takemasa Miyoshi, Keiichi Kondo, and Roland Potthast
Geosci. Model Dev., 15, 8325–8348, https://doi.org/10.5194/gmd-15-8325-2022, https://doi.org/10.5194/gmd-15-8325-2022, 2022
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Data assimilation plays an important part in numerical weather prediction (NWP) in terms of combining forecasted states and observations. While data assimilation methods in NWP usually assume the Gaussian error distribution, some variables in the atmosphere, such as precipitation, are known to have non-Gaussian error statistics. This study extended a widely used ensemble data assimilation algorithm to enable the assimilation of more non-Gaussian observations.
Juan Ruiz, Pierre Ailliot, Thi Tuyet Trang Chau, Pierre Le Bras, Valérie Monbet, Florian Sévellec, and Pierre Tandeo
Geosci. Model Dev., 15, 7203–7220, https://doi.org/10.5194/gmd-15-7203-2022, https://doi.org/10.5194/gmd-15-7203-2022, 2022
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We present a new approach to validate numerical simulations of the current climate. The method can take advantage of existing climate simulations produced by different centers combining an analog forecasting approach with data assimilation to quantify how well a particular model reproduces a sequence of observed values. The method can be applied with different observations types and is implemented locally in space and time significantly reducing the associated computational cost.
Takemasa Miyoshi and Qiwen Sun
Nonlin. Processes Geophys., 29, 133–139, https://doi.org/10.5194/npg-29-133-2022, https://doi.org/10.5194/npg-29-133-2022, 2022
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The weather is chaotic and hard to predict, but the chaos implies an effective control where a small control signal grows rapidly to make a big difference. This study proposes a control simulation experiment where we apply a small signal to control
naturein a computational simulation. Idealized experiments with a low-order chaotic system show successful results by small control signals of only 3 % of the observation error. This is the first step toward realistic weather simulations.
Juan Ruiz, Guo-Yuan Lien, Keiichi Kondo, Shigenori Otsuka, and Takemasa Miyoshi
Nonlin. Processes Geophys., 28, 615–626, https://doi.org/10.5194/npg-28-615-2021, https://doi.org/10.5194/npg-28-615-2021, 2021
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Effective use of observations with numerical weather prediction models, also known as data assimilation, is a key part of weather forecasting systems. For precise prediction at the scales of thunderstorms, fast nonlinear processes pose a grand challenge because most data assimilation systems are based on linear processes and normal distribution errors. We investigate how, every 30 s, weather radar observations can help reduce the effect of nonlinear processes and nonnormal distributions.
Cited articles
Amezcua, J., Ide, K., Bishop, C. H., and Kalnay, E.: Ensemble clustering in deterministic ensemble Kalman filters, Tellus A: Dynamic Meteorology and Oceanography, 64, 18039, https://doi.org/10.3402/tellusa.v64i0.18039, 2012. a
Bengtsson, T., Snyder, C., and Nychka,D.: Toward a nonlinear ensemble filter for high-dimensional systems, J. Geophys. Res., 108, 8775, https://doi.org/10.1029/2002JD002900, 2003. a
Bishop, C. H., Etherton, B. J., and Majumdar, S. J.: Adaptive Sampling with the Ensemble Transform Kalman Filter. Part I: Theoretical Aspects, Monthly Weather Review, 129, 420–436, https://doi.org/10.1175/1520-0493(2001)129<0420:aswtet>2.0.co;2, 2001. a
Cotter, C. and Crisan, D., Holm, D., Pan, W., and Shevchenko, I.: A Particle Filter for Stochastic Advection by Lie Transport: A Case Study for the Damped and Forced Incompressible Two-Dimensional Euler Equation, SIAM/ASA Journal on Uncertainty Quantification, 8, 1446–1492, https://doi.org/10.1137/19M1277606, 2020. a
Daum, F., Huang, J., and Noushin, A.: Exact particle flow for nonlinear filters, in: Signal processing, sensor fusion, and target recognition XIX, Vol. 7697, SPIE, 92–110, https://doi.org/10.1117/12.839590, 2010. a
Del Moral, P.: Mean field simulation for Monte Carlo integration, Monographs on Statistics and Applied Probability, 126, 26, ISBN 978-1-4665-0417-2, 2013. a
Doucet, A., de Freitas, N., and Gordon, N.: Sequential Monte Carlo Methods in Practice, Springer, https://doi.org/10.1007/978-1-4757-3437-9, 2001. a
Farchi, A. and Bocquet, M.: Review article: Comparison of local particle filters and new implementations, Nonlinear Processes in Geophysics, 25, 765–807, https://doi.org/10.5194/npg-25-765-2018, 2018. a
Gallego, V. and Rios Insua, D.: Stochastic gradient MCMC with repulsive forces, arXiv [preprint], https://doi.org/10.48550/arXiv.1812.00071, 2018. a, b
Gaspari, G. and Cohn, S. E.: Construction of correlation functions in two and three dimensions, Quarterly Journal of the Royal Meteorological Society, 125, 723–757, https://doi.org/10.1002/qj.49712555417, 1999. a
Hamill, T. M., Whitaker, J. S., and Snyder, C.: Distance-dependent filtering of background error covariance estimates in an ensemble Kalman filter, Monthly Weather Review, 129, 2776–2790, 2001. a
Hohenegger, C. and Schar, C.: Atmospheric Predictability at Synoptic Versus Cloud-Resolving Scales, Bulletin of the American Meteorological Society, 88, 1783–1794, https://doi.org/10.1175/bams-88-11-1783, 2007. a
Houtekamer, P. L. and Mitchell, H. L.: A sequential ensemble Kalman filter for atmospheric data assimilation, Monthly Weather Review, 129, 123–137, 2001. a
Hu, C. and van Leeuwen, P. J.: A particle flow filter for high‐dimensional system applications, Quarterly Journal of the Royal Meteorological Society, 147, 2352–2374, https://doi.org/10.1002/qj.4028, 2021. a, b
Hunt, B. R., Kostelich, E. J., and Szunyogh, I.: Efficient data assimilation for spatiotemporal chaos: A local ensemble transform Kalman filter, Physica D: Nonlinear Phenomena, 230, 112–126, https://doi.org/10.1016/j.physd.2006.11.008, 2007. a, b
Jordan, R., Kinderlehrer, D., and Otto, F.: The variational formulation of the Fokker–Planck equation, SIAM Journal on Mathematical Analysis, 29, 1–17, 1998. a
Kingma, D. P. and Ba, J.: Adam: A method for stochastic optimization, International Conference for Learning Representations, arXiv [preprint] https://doi.org/10.48550/arXiv.1412.6980, 2014. a, b, c
Kurosawa K. and Poterjoy, J.: Data Assimilation Challenges Posed by Nonlinear Operators: A Comparative Study of Ensemble and Variational Filters and Smoothers, Monthly Weather Review, 149, 2369–2389, https://doi.org/10.1175/MWR-D-20-0368.1, 2021. a
Leviyev, A., Chen, J., Wang, Y., Ghattas, O., and Zimmerman, A.: A stochastic stein variational newton method, arXiv [preprint], https://doi.org/10.48550/arXiv.2204.09039, 2022. a
Liu, Q. and Wang, D.: Stein Variational Gradient Descent: A General Purpose Bayesian Inference Algorithm, Advances in Neural Information Processing Systems, 29, https://proceedings.neurips.cc/paper_files/paper/2016/file/b3ba8f1bee1238a2f37603d90b58898d-Paper.pdf (last access: 20 January 2026), 2016. a, b, c
Lorenz, E. N. and Emanuel, K. A.: Optimal Sites for Supplementary Weather Observations: Simulation with a Small Model, Journal of the Atmospheric Sciences, 55, 399–414, https://doi.org/10.1175/1520-0469(1998)055<0399:OSFSWO>2.0.CO;2, 1998. a
Lorenz, E. N.: Designing Chaotic Models, Journal of the Atmospheric Sciences, 62, 1574–1587, https://doi.org/10.1175/jas3430.1, 2005. a
Lu, J., Lu, Y., and Nolen, J.: Scaling limit of the Stein variational gradient descent: The mean field regime, SIAM Journal on Mathematical Analysis, 51, 648–671, 2019. a
Ma, Y.-A., Chen, T., and Fox, E.: A complete recipe for stochastic gradient MCMC, Advances in Neural Information Processing Systems, 28, https://proceedings.neurips.cc/paper_files/paper/2015/file/9a4400501febb2a95e79248486a5f6d3-Paper.pdf (last access: 20 January 2026), 2015. a
Neal, R. M.: Sampling from multimodal distributions using tempered transitions, Statistics and Computing, 6, 353–366, https://doi.org/10.1007/bf00143556, 1996. a
Penny, S. G. and Miyoshi, T.: A local particle filter for high-dimensional geophysical systems, Nonlinear Processes in Geophysics , 23, 391–405, https://doi.org/10.5194/npg-23-391-2016, 2016. a
Poterjoy, J.: A localized particle filter for high-dimensional nonlinear systems, Monthly Weather Review, 144, 59–76, https://doi.org/10.1175/mwr-d-15-0163.1, 2016. a
Pulido, M., Scheffler, G., Ruiz, J. J., Lucini, M. M., and Tandeo, P.: Estimation of the functional form of subgrid-scale parametrizations using ensemble-based data assimilation: a simple model experiment, Quarterly Journal of the Royal Meteorological Society, 142, 2974–2984, https://doi.org/10.1002/qj.2879, 2016. a
Pulido, M. and van Leeuwen, P. J.: Sequential Monte Carlo with kernel embedded mappings: The mapping particle filter, Journal of Computational Physics, 396, 400–415, https://doi.org/10.1016/j.jcp.2019.06.060, 2019. a, b, c, d
Robert, S. and Künsch, H. R.: Localizing the Ensemble Kalman Particle Filter, Tellus A: Dynamic Meteorology and Oceanography, 69, 1282016, https://doi.org/10.1080/16000870.2017.1282016, 2017. a
Ruiz, J., Lien, G.-Y., Kondo, K., Otsuka, S., and Miyoshi, T.: Reduced non-Gaussianity by 30 s rapid update in convective-scale numerical weather prediction, Nonlinear Processes in Geophysics, 28, 615–626, https://doi.org/10.5194/npg-28-615-2021, 2021. a
Snyder, C., Bengtsson, T., Bickel, P., and Anderson, J.: Obstacles to high-dimensional particle filtering, Monthly Weather Review, 136, 4629–4640, https://doi.org/10.1175/2008mwr2529.1, 2008. a
Subrahmanya, A. N., Popov, A. A., and Sandu, A.: Ensemble variational Fokker-Planck methods for data assimilation, Journal of Computational Physics, 523, 113681, https://doi.org/10.1016/j.jcp.2024.113681, 2025. a
Tabak, E. G. and Turner, C. V.: A Family of Nonparametric Density Estimation Algorithms, Communications on Pure and Applied Mathematics, 66, 145–164, https://doi.org/10.1002/cpa.21423, 2012. a
van Leeuwen, P. J.: Nonlinear ensemble data assimilation for the ocean. In seminar Recent Developments in Data Assimilation for Atmosphere and Ocean, ECMWF, Reading, UK, 8–12 September, https://www.ecmwf.int/en/elibrary/77010-nonlinear-ensemble-data-assimilation-ocean (last access: 20 January 2026), 2003. a
van Leeuwen, P. J., Künsch, H. R., Nerger, L., Potthast, R., and Reich, S.: Particle filters for high-dimensional geoscience applications: A review, Quarterly Journal of the Royal Meteorological Society, 145, 2335–2365, https://doi.org/10.1002/qj.3551, 2019. a, b, c
Wang, D., Zeng, Z., and Liu, Q.: Stein variational message passing for continuous graphical models, International Conference on Machine Learning, 5219–5227, https://proceedings.mlr.press/v80/wang18l.html (last access: 20 January 2026), 2018. a
Wilks, D. S.: Effects of stochastic parameterizations in the Lorenz 96 system, Quarterly Journal of the Royal Meteorological Society, 131, 389–407, https://doi.org/10.1256/qj.04.03, 2005. a
Whitaker, J. S. and Hamill, T. M.: Ensemble data assimilation without perturbed observations, Monthly Weather Review, 130, 1913–1924, 2002. a
Short summary
This work extends the Mapping Particle Filter to account for local dependencies. Two localization methods are tested: a global particle flow with local kernels, and iterative local mappings based on correlation radius. Using a two-scale Lorenz-96 truth and a one-scale forecast model, experiments with full/partial and linear/nonlinear observations show Root Mean Square Error reductions using localized Gaussian mixture priors, achieving competitive performance against Gaussian filters.
This work extends the Mapping Particle Filter to account for local dependencies. Two...