Density assimilated reduced order state for thermosphere-ionosphere drag estimation

Data product provided along with paper - Reduced-Order Data Assimilation for Thermospheric Density Using Physics-informed SINDyc Models.

The file ark_results_full_V2.h5 contains:

• timestamps — UT epoch of each filter step.
• z_filt — posterior (filtered) ROM state coefficients at each step.
• z_openloop — free-running ROM state coefficients (no measurement updates) for baseline comparison.
• window_log — per-window assimilation summary.
• steplog/ — per-step Kalman filter diagnostics:
  • trace_P — trace of the posterior covariance (the A-optimal scalar).
  • diag_P — diagonal of the posterior covariance (marginal variances of each ROM coefficient).
  • NIS — Normalised Innovation Squared, for filter consistency checks.
  • innov_rms — RMS of the innovation vector.
  • n_meas — number of measurements assimilated at each step.
  • sat_log — IDs of the satellites contributing measurements at each step.
  • mode — filter operating mode flag.

All step-indexed arrays are aligned with timestamps. Accompanying notebook and .py files are provided to support reconstruction.

For sample assimilaition code, please see - https://doi.org/10.5281/zenodo.19947885