M-I Coupling: Incoherent Scatter Radar Measurements of Ion Upflow: Establishing Ionospheric Boundary Conditions for Magnetosphere-Ionosphere Mass Coupling

Sri International, Menlo Park CA

Investigators

Abstract

Spacecraft observations have established the general properties of ion outflows for different solar and interplanetary wind inputs, seasons, and local times, but they have not provided an understanding of what the ionospheric conditions are that enables the most efficient ion extraction. This project will utilize Incoherent Scatter radar (ISR) data along with satellite/radar conjunctions to determine the altitude profiles of field-aligned ion number flux, electron density, electron temperature, and ion temperature associated with ion outflow events. The project will determine how the ion energization that produces ion upflows in the F region of the ionosphere relates to energization processes that produce ion outflows at higher altitudes. It will quantify the net upward ion flux above the topside ionosphere as a function of external energy input (from the convection electric field, particle precipitation and EUV irradiation) and ionospheric boundary conditions. An expanded ISR database, spanning one solar cycle, will be used to quantify statistically the same ionospheric parameters and their vertical gradients as functions of particle precipitation, heat flux, convection electric field, and solar illumination in the frame of reference of auroral oval boundaries. The project has a strong societal impact because it will bring space research one step closer to achieving a predictive space weather capability. At the present time, MHD models of the magnetosphere have a well-developed formalism to describe mass loading from the solar wind, but they lack a formalism to describe mass loading from the ionosphere. The statistical maps generated by this project will establish the lower boundary condition for all ion extraction models, which in turn can be coupled to upper boundary conditions from the MHD magnetosphere models to produce a self-consistent picture of ionospheric mass loading of the magnetosphere. The results will be made available on publicly accessible FTP and websites at SRI International.