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�THE ATMOSPHERE VARIABILITY CLUSTER G2A

SUMMARY AND ACTIONS��

Sean Bruinsma

CNES, Space Geodesy Office

Toulouse, France

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ISWAT Working Meeting

14 February 2025

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ISWAT Atmosphere Variability - G2A

G2a-03 Satellite aerodynamic modeling (lead: Piyush Mehta) – Monday PM1-PM2

  • Significant progress has been made in the community towards improving and advancing knowledge of gas-surface interaction physics. We seem to be converging. The primary goal now is to establish a baseline for the different elements to estimate the drag coefficient.
  • Need to establish a baseline

Reflection Kernel

Accommodation Model

Computational Approach

Free Stream Conditions

  • Cd software
  • Consistency with operations
  • Add information on Cd model used and reference area to the density datasets

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ISWAT Atmosphere Variability - G2A

Data Assimilation for density prediction (lead: Shaylah Mutschler) – Tuesday AM1-AM2-PM1

    • NEW DA action team, also in cluster O3-A

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ISWAT Atmosphere Variability - G2A

G2a-01 Thermosphere model assessment and improvement (lead: Sean Bruinsma) – Wed AM1-AM2

    • Assessment of drivers, models, and predicted densities is desired – drivers scoreboard being created now, model assessment almost done, predicted densities with and without DA should be created
    • Request Space Force density data for the assessment
    • TU Delft will recalculate all accelerometer and Swarm densities once Cd model finished (in 1 or 2 years)
    • Efforts are made to extend HASDM database by SET and EDR densities by NRL
    • Drive down biases between density and temperature datasets
    • Geomagnetic modeling needs improvement, most importantly in the recovery phase. Also need to take advantage of the higher cadence Hpo index

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ISWAT Atmosphere Variability - G2A

Joint G2a & S2-02 session on solar indices – Thursday PM1

    • very good session, good discussion between S and G

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ISWAT Atmosphere Variability - G2A

G2a-02 Space Weather and Lower Atmosphere (lead: Jia Yue) – no session

    • Reentry study with WACCMX, TIEGCM, MSIS and DTM (almost finished)