Work at SRI involved modeling the exchange of electromagnetic energy between the ionosphere and magnetosphere to help interpret the DE-B Poynting flux observations. To describe the electrical properties of the high-latitude ionosphere, we constructed a numerical model, from the framework provided by the Vector Spherical Harmonic (VSH) model, that determines the ionospheric currents, conductivities, and electric fields including both magnetospheric inputs and neutral wind dynamo effects. This model development grew from the earlier question of whether an electrical energy source in the ionosphere was capable of providing an upward Poynting flux. The model solves the steady-state neutral wind dynamo equations and the Poynting flux equation to provide insight into the electrodynamic role of the neutral winds. The modeling effort to determine the high-latitude energy flux has been able to reproduce many of the large-scale features observed in the Poynting flux measurements made by DE-2. Because the Poynting flux measurement is an integrated result of energy flux into or out of the ionosphere, we investigated the ionospheric properties that may contribute to the observed flux of energy measured by the spacecraft. During steady state the electromagnetic energy flux, or DC Poynting flux, is equal to the Joule heating rate and the mechanical energy transfer rate in the high-latitude ionosphere. Although the Joule heating rate acts as an energy sink, transforming electromagnetic energy into thermal or internal energy of the gas, the mechanical energy transfer rate may be either a sink or source of electromagnetic energy. In the steady state, it is only the mechanical energy transfer rate that can generate electromagnetic energy and result in a DC Poynating flux that is directed out of the ionosphere. Thayer, J. P. and Vickrey, J. F. and Heelis, R. A. and Gary, J. B. Unspecified Center...

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This book is a multi-author treatise on the most outstanding research problems in the field of the aeronomy of the Earth’s atmosphere and ionosphere, encompassing the science covered by Division II of the International Association of Geomagnetism and Aeronomy (IAGA). It contains several review articles and detailed papers by leading scientists in the field. The book is organized in five parts: 1) Mesosphere-Lower Thermosphere Dynamics and Chemistry; 2) Vertical Coupling by Upward Propagating Waves; 3) Ionospheric Electrodynamics and Structuring; 4) Thermosphere- Ionosphere Coupling, Dynamics and Trends and 5) Ionosphere-Thermosphere Disturbances and Modeling. The book consolidates the progress achieved in the field in recent years and it serves as a useful reference for graduate students as well as experienced researchers.

Over a half century of exploration of the Earth’s space environment, it has become evident that the interaction between the ionosphere and the magnetosphere plays a dominant role in the evolution and dynamics of magnetospheric plasmas and fields. Interestingly, it was recently discovered that this same interaction is of fundamental importance at other planets and moons throughout the solar system. Based on papers presented at an interdisciplinary AGU Chapman Conference at Yosemite National Park in February 2014, this volume provides an intellectual and visual journey through our exploration and discovery of the paradigm-changing role that the ionosphere plays in determining the filling and dynamics of Earth and planetary environments. The 2014 Chapman conference marks the 40th anniversary of the initial magnetosphere-ionosphere coupling conference at Yosemite in 1974, and thus gives a four decade perspective of the progress of space science research in understanding these fundamental coupling processes. Digital video links to an online archive containing both the 1974 and 2014 meetings are presented throughout this volume for use as an historical resource by the international heliophysics and planetary science communities. Topics covered in this volume include: Ionosphere as a source of magnetospheric plasma Effects of the low energy ionospheric plasma on the stability and creation of the more energetic plasmas The unified global modeling of the ionosphere and magnetosphere at the Earth and other planets New knowledge of these coupled interactions for heliophysicists and planetary scientists, with a cross-disciplinary approach involving advanced measurement and modeling techniques Magnetosphere-Ionosphere Coupling in the Solar System is a valuable resource for researchers in the fields of space and planetary science, atmospheric science, space physics, astronomy, and geophysics. Read an interview with the editors to find out more: https://eos.org/editors-vox/filling-earths-space-environment-from-the-sun-or-the-earth

Perturbation electric and magnetic fields carry in excess of 10(exp10) to 10(exp12) W of electrical power between the magnetosphere and high-latitude ionosphere. Most of this power is generated by the solar wind. The ionosphere at large spatial and temporal scales acts as a dissipative slab which can be characterized by its height-integrated Pedersen conductivity sigma p, so that the power flux into the ionosphere due to a quasi-static electric field E is given by sigma (pE2) The energy transferred to the ionosphere by time-varying electromagnetic fields in the form of Alfven waves is more difficult to calculate because density and conductivity gradients can reflect energy. Thus, field resonances and standing wave patterns affect the magnitude and altitude distribution of electrical energy dissipation. We use a numerical model to calculate the frequency-dependent electric field reflection coefficient of the ionosphere and show that the ionosphere does not behave as a simple resistive slab for electric field time scales less than a few seconds. Time variation of spacecraft-measured high-latitude electric and perturbation magnetic fields is difficult to distinguish from spatial structuring that has been Doppler-shifted to a non-zero frequency in the spacecraft frame. However, by calculating the frequency-dependent amplitude and phase relations between fluctuating electric and magnetic fields we are able to show that low frequency fields (

This volume gives a broad synthesis of the current knowledge and understanding of the plasma physics behind the aurora. The aurora is not only one of the most spectacular natural phenomena on Earth, but the underlying physical processes are expected to be ubiquitous in the plasma universe. Recognizing the enormous progress made over the last decade) through in situ and groundbased measurements as well as theoretical modelling, it seemed timely to write the first comprehensive and integrated book on the subject. Recent advances concern the clarification of the nature of the acceleration process of the electrons that are responsible for the visible aurora, the recognition of the fundamental role of the large-scale current systems in organizing the auroral morphology, and of the interplay between particles and electromagnetic fields.