Global Plasmaspheric Electron Density Simulations of Pre-dawn and Post-dusk Geomagnetic Events Observed by the Van Allen Probes

Sebastian De Pascuale, University of Iowa, Iowa City, IA, United States, Vania K Jordanova, Los Alamos National Laboratory, Los Alamos, NM, United States, Jerry Goldstein, Southwest Research Institute San Antonio, San Antonio, TX, United States and Craig Kletzing, University of Iowa, Physics and Astronomy, Iowa City, United States

Contact First Author: Sebastian De Pascuale; sebastian-depascuale@uiowa.edu

Previously Published Material: A poster on the content of this proposal was presented at the 2014 AGU Fall Meeting in San Francisco, CA under the Dawn-Dusk Asymmetries in Solar Wind-Magnetosphere-Ionosphere Systems session. The findings were also reported in an internal Los Alamos Space Weather Summer School Research Reports circulation at LANL, but have not yet been submitted for peer-review. That work is currently in preparation for submission to the Journal of Geophysical Research.

Abstract ID#: 34347

 

English Abstract:
We use in situ measurements by the Van Allen Probes (RBSP) to validate a globally applicable plasmaspheric electron density model (RAM-CPL), which is based on ionospheric outflow rates and electric field drivers as proxies for system refilling and erosion respectively. The model is a key component of the RAM-CPL suite in describing the temporal evolution of plasma density in the equatorial plane of the magnetosphere. In addition to considering absolute density values, this study employs a composite definition of the plasmapause boundary as a standard metric for comparison between observations and the model. Because the dynamics of the plasmasphere are governed on different timescales ranging from minutes to days, we consider geomagnetic events for which the RBSP satellites are at conjunction to sample fine-scale density variation as well as large-scale structure. Furthermore, the pre-dawn and post-dusk sectors of the observations provide adequate constraints on the candidate electric field drivers of the plasmasphere. The good agreement attained by the RAM-CPL plasmasphere model can be utilized to predict density conditions in magnetic local time and L-parameter sectors distant from an RBSP orbit of interest. These simulations reproduce plasmapause radial locations to within 0.6 Earth radii (RE) of RBSP observations and we investigate further the competing effects of plasmaspheric refilling and erosion on model performance.
Back to: Earth's Plasmasphere: Feeding, Dynamics, and Coupling Processes I