1. Data assimilation - the collaborative research centre SFB1294
  2. Research
  3. Research Area B
  4. B06

B06 – Reconstructing and predicting the near-Earth radiation environment utilising dimension reduction

Energetic particles in the near-Earth space environment threaten satellite infrastructure and human activities in space. Understanding and predicting their dynamics remains a key challenge in space weather research. During geomagnetic storms [6], particle fluxes in the inner magnetosphere can intensify rapidly, leading to satellite anomalies and even failures. Measurements from multiple spacecraft must be integrated to accurately capture the global state of cold and hot particle populations. The goal of B06 is to provide global reconstructions of the particle populations to overcome the limitations of sparse satellite observations.

In the third funding period, we will combine the tools and optimize our codes from the previous two periods to study the whole electron energy spectrum, starting from eV energies up to 10 MeV particles, covering seven orders of magnitude. 

During the first funding period, we used suboptimal approaches and simplified treatment of the problem as three 1D models for higher energy and a series of 2D models for lower energy, the accurate treatment of the problem requires data assimilation in 4D, which will cover all energies containing electron populations controlled by different physical processes. We will therefore use dimension reduction within data assimilation to make the full 4D treatment computationally feasible. 

Real time display shown at https://www.gfz-potsdam.de/sektion/magnetosphaerenphysik/daten-produkte-dienste. Two-day radiation belt forecast of 1 MeV electrons using the data-assimilative VERB code, real-time ARASE, ACE, POES and GOES data. (Top left) real-time satellite trajectories and geometry of the magnetic field lines used to calculate magnetic coordinates (adiabatic invariants) for data assimilation. (Bottom left) 3D snapshot of the radiation belts. (right panels) Top panel shows real-time satellite measurements. Second panel illustrates the measurements interpolated into the model grid in the equatorial plane at 1 MeV energy and 50° equatorial pitch angle. Third panel shows the reanalysis of the radiation belts and a two day prediction into the future. Last two panels show propagated solar wind parameters measured at L1 and the Kp index of geomagnetic activity, respectively. The dashed red line demarcates historical reanalysis from the forecast for 2 days ahead of real-time.

  • Castillo, A. M., de Wiljes, J., Shprits, Y. Y., and Aseev, N. A. (2020). Reconstructing the dynamics of the outerelectron radiation belt by means of the standard and ensemble Kalman filter with the VERB-3Dcode, ESSOAr. doi:10.1002/essoar.10504674.

  • Zhelavskaya, I., Aseev, N. A., Shprits, Y. Y., and Spasojevi, M. (2020). A combined neural network- and physics-based approach for modeling the plasmasphere dynamics, ESSOAr. doi:10.1002/essoar.10502691.1

  • Castillo, A. M., Shprits, Y. Y., Aseev, N. A., Smirnov, A., Drozdov, A., Cervantes, S., et al. (2024): Can we intercalibrate satellite measurements by means of data assimilation? An attempt on LEO satellites. Space Weather, 22, e2023SW003624. doi: 10.1029/2023SW003624

  • Haas, B., Shprits, Y. Y., Wutzig, M., Szabó-Roberts, M., García Peñaranda, M., Castillo Tibocha, A. M., Himmelsbach, J., Wang, D., Miyoshi, Y., Kasahara, S., Keika, K., Yokota, S., Shinohara, I., and Hori, T. (2024). Global validation of data-assimilative electron ring current nowcast for space weather applications.Sci Rep 14, 2327. doi: 10.1038/s41598-024-52187-0.

  • Castillo Tibocha, A. M., de Wiljes, J., Shprits, Y. Y., & Aseev, N. A. (2021). Reconstructing the dynamics of the outer electron radiation belt by means of the standard and ensemble Kalman filter with the VERB-3D code. Space Weather, 19, e2020SW002672, doi: 10.1029/2020SW002672

  • Zhelavskaya, I. S., Aseev, N. A., and Shprits, Y. Y. (2021): A combined neural network- and physics-based approach for modeling plasmasphere dynamics. Journal of Geophysical Research: Space Physics, 126, e2020JA028077, doi: 10.1029/2020JA028077

  • Cervantes, S., Shprits, Y. Y., Aseev, N. A., and Allison, H. J. (2020). Quantifying the effects of EMIC wavescattering and magnetopause shadowing in the outer electron radiation belt by means of data as-similation. J. Geophys. Res.-Space, 125(8):e2020JA028208, doi:10.1029/2020JA028208

  • Ruchi, A., Dubinkina, S., and de Wiljes, J. (2020). Fast hybrid tempered ensemble transform filter for Bayesianelliptical problems. Nonlin. Processes Geophys., in press, doi:10.5194/npg-2020-24

  • Hamm, M., Pelivan, I., Grott, M., and de Wiljes, J. (2020). Thermophysical modelling and parameter esti-mation of small solar system bodies via data assimilation. Mon. Not. R. Astron. Soc., 496:2776–2785, doi:10.1093/mnras/staa1755

  • Cervantes, S., Shprits, Y. Y., Aseev, N., Drozdov, A., Castillo, A., and Stolle, C. (2020). Identifying radiation beltelectron source and loss processes by assimilating spacecraft data in a three-dimensional diffusionmodel. J. Geophys. Res.-Space, 125(1):1–16, doi:10.1029/2019JA027514

  • Castillo, A. M., Shprits, Y. Y., Ganushkina, N., Drozdov, A., Aseev, N., Wang, D. and Dubyagin, S. (2019). Simulations of the inner magnetospheric energetic electrons using the IMPTAM-VERB coupled model. Journal of Atmospheric and Solar-Terrestrial Physics. doi: 10.1016/j.jastp.2019.05.014 

  • Aseev, N. A. and Shprits, Y. Y. (2019). Reanalysis of ring current electron phase space densities using Van AllenProbe observations, convection model, and log-normal Kalman Filter. Space Weather, 17(4):619–638, doi:10.1029/2018SW002110

  • Aseev, N. A., Shprits, Y. Y., Wang, D., Wygant, J., Drozdov, A. Y., Kellerman, A. C., and Reeves, G. D. (2019). Transport and loss of ring current electrons inside geosynchronous orbit during the 17 March 2013 storm. J. Geophys. Res.-Space, 124(2):915–933. doi:10.1029/2018JA026031

  • Ni, B., Cao, X., Shprits, Y. Y., Summers, D., Gu, X., Fu, S. and Lou, Y. (2018). Hot Plasma Effects on the Cyclotron-Resonant Pitch-Angle Scattering Rates of Radiation Belt Electrons Due to EMIC Waves. Geophysical Research Letters, 45, 21-30. doi: 10.1002/2017GL07602

  • Zhelavskaya, I. S., Shprits, Y. Y. and Spasojevic, M. (2017): Empirical modeling of the plasmasphere dynamics using neural networks. Journal of Geophysical Research: Space Physics, 122, 11227–11244. doi:10.1002/2017JA024406

  • Aseev, N. A., Shprits, Y. Y., Drozdov, A. Y., Kellerman, A. C., Usanova, M. E., Wang, D. and Zhelavskaya, I. S. (2017): Signatures of Ultrarelativistic Electron Loss in the Heart of the Outer Radiation Belt Measured by Van Allen Probes. Journal of Geophysical Research, 122, 10102-10111. doi: 10.1002/2017JA024485

  • Borovsky, J. E. and Shprits, Y. Y. (2017): Is the Dst Index Sufficient to Define All Geospace Storms?. Journal of Geophysical Research: Space Physics, 122, 11543-11547. doi:10.1002/2017JA024679