SA23E-03
Dynamics of Subauroral Polarization Stream (SAPS) Structures
Tuesday, 15 December 2015: 14:10
2016 (Moscone West)
Stanislav Y Sazykin1, Anthea J Coster2, Joseph Huba3, Aaron J Ridley4, Philip John Erickson2, John C Foster2, Joseph B. H. Baker5 and Richard Wolf1, (1)Rice University, Houston, TX, United States, (2)MIT Haystack Observatory, Westford, MA, United States, (3)US Naval Research Laboratory, Washington, DC, United States, (4)University of Michigan Ann Arbor, AOSS, Ann Arbor, MI, United States, (5)Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
Abstract:
The Subauroral Polarization Stream (SAPS) flow structures are narrow ionospheric channels of fast (in excess of 100 m/s) westward drift just outside the equatorward edge of the diffuse aurora in the dusk-to-midnight local time sector. Other terms for this phenomenon include subauroral Ion Drift (SAID) events and Polarization Jets. SAPS structures represent a striking departure from the commonly-used two-cell convection pattern. They are thought to arise from the displacement of the downward region-2 Birkeland currents on the dusk side equatorward of the low-latitude boundary of the auroral oval during times of changing high-latitude convection. In this paper, we will use several event simulations with the SAMI3-RCM numerical model (a self-consistent ionosphere-inner magnetosphere model) and RCM-GITM (a self-consistent model of the ionosphere-thermosphere-inner magnetosphere) to analyze the relative roles of changes in the IMF Bz component, ionospheric electron density depletions, and thermospheric modifications in controlling the dynamics of SAPS. Simulation results will be compared to multi-instrument ionospheric observations.
