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NASA NTRSDate not supplied

Modeling and Visualization of Geomagnetic Storms at the CCMC

The Community Coordinated Modeling Center is greatly expanding activities in geospace in recent years, including the addition of new models or outputs (including WACCM-X, SAMI3-TIEGCM, HYPERS, GAMERA test runs and WAM-IPE real time outputs) that expand the range of available views or analysis activities in geospace during the upcoming Solar Maximum and Heliophysics Big Year. We are now routinely adding to a library of geomagnetic storms using anew request interface for the Space Weather Modeling Framework(SWMF). We are placing continuous run model simulation outputs as run series onto the CCMC web site where look at quick-look graphics, perform online visualization and request outputs for any day covered by the results.We demonstrate examples and results of online visualization and analysis tools that are also placed onto the cloud to support Open Science and collaborative research.

Lutz Rastaetter↗
NASA NTRSDate not supplied

What Processes are Defining the Ionospheric Conductivity and its Variability During Geomagnetic Disturbances?

Modeling of electrodynamic coupling between the magnetosphere, ionosphere, and upper atmosphere (MIA) depends on accurate specification of ionospheric conductance produced by auroral precipitation of high-energy electrons and ions. The precipitation of energetic electrons into the ionosphere is the result of a three-step process that relies on the proper selections of the simulation tools for the ionospheric conductivity studies, while observation can only measure the results of the three steps. In the region of diffuse aurora, the first step is the initiation of electron precipitation into both magnetically conjugate foot points from the Earth’s magnetosphere via wave-particle interactions. The second step is the multiple atmospheric backscatters (or reflections) of electrons at the two magnetic conjugate points, which produces secondary superthermal electron fluxes. The third step is namely the self-consistent electric and magnetic fields that influence magnetospheric particle transport and re-distribute precipitating electrons and ions through the ionospheric electrodynamics. These steps are especially important for revealing electron precipitation dynamics that carry most of the energy in the aurora, resulting also from ion precipitation production and the formation of ionospheric conductance during geomagnetic disturbances. We demonstrate all above results based on SuperThermal Electron Transport (STET), Superthermal Proton, Electron and Atomic Hydrogen tRansport in the Ionosphere and Thermosphere (SPEAH-RIT), and Comprehensive Inner Magnetosphere and Ionospere (CIMI) codes developed at NASA Goddard Space Flight Center.

George V. Khazanov↗
NASA NTRS2023

Comparing Magnetopause Predictions From Two MHD Models During A Geomagnetic Storm and A Quiet Period

Magnetopause location is an important prediction of numerical simulations of the magnetosphere, yet the models can err, either under-predicting or over-predicting the motion of the boundary. This study compares results from two of the most widely used magnetohydrodynamic (MHD) models, the Lyon–Fedder–Mobarry (LFM) model and the Space Weather Modeling Framework (SWMF), to data from the GOES 13 and 15 satellites during the geomagnetic storm on 22 June 2015, and to THEMIS A, D, and E during a quiet period on 31 January 2013. The models not only reproduce the magnetopause crossings of the spacecraft during the storm, but they also predict spurious magnetopause motion after the crossings seen in the GOES data. We investigate the possible causes of the over-predictions during the storm and find the following. First, using different ionospheric conductance models does not significantly alter predictions of the magnetopause location. Second, coupling the Rice Convection Model (RCM) to the MHD codes improves the SWMF magnetopause predictions more than it does for the LFM predictions. Third, the SWMF produces a stronger ring current than LFM, both with and without the RCM and regardless of the LFM spatial resolution. During the non-storm event, LFM predicts the THEMIS magnetopause crossings due to the southward interplanetary magnetic field better than the SWMF. Additionally, increasing the LFM spatial grid resolution improves the THEMIS predictions, while increasing the SWMF grid resolutions does not.

magnetohydrodynamics↗