The purpose of this paper is to introduce the reader to the active sun as a source of disturbance that affect the magnetic field measured at the earth's surface. Included under this topic are the general sun's properties, solar surface activity centers and characteristics of the solar field and ejecta flowing into interplanetary space.

An interdisciplinary review of research in geomagnetism, aeronomy and space weather, written by eminent researchers from these fields.

The magnetotelluric method is a technique for imaging the electrical conductivity and structure of the Earth, from the near surface down to the 410 km transition zone and beyond. This book forms the first comprehensive overview of magnetotellurics, from the salient physics and its mathematical representation to practical implementation in the field, data processing, modeling and geological interpretation. Electromagnetic induction in 1-D, 2-D and 3-D media is explored, building from first principles, and with thorough coverage of the practical techniques of time series processing, distortion, numerical modeling and inversion. The fundamental principles are illustrated with a series of case histories describing geological applications. Technical issues, instrumentation and field practices are described for both land and marine surveys. This book provides a rigorous introduction to magnetotellurics for academic researchers and advanced students, and will be of interest to industrial practitioners and geoscientists wanting to incorporate rock conductivity into their interpretations.

This open access book provides a comprehensive toolbox of analysis techniques for ionospheric multi-satellite missions. The immediate need for this volume was motivated by the ongoing ESA Swarm satellite mission, but the tools that are described are general and can be used for any future ionospheric multi-satellite mission with comparable instrumentation. In addition to researching the immediate plasma environment and its coupling to other regions, such a mission aims to study the Earth’s main magnetic field and its anomalies caused by core, mantle, or crustal sources. The parameters for carrying out this kind of work are examined in these chapters. Besides currents, electric fields, and plasma convection, these parameters include ionospheric conductance, Joule heating, neutral gas densities, and neutral winds.

Previous research results on high latitude sporadic E are surveyed, and replotted and displayed in Corrected Geomagnetic Latitude (CGL) AND Corrected Geomagnetic Time (CGT) and related to current research results. Patterns of occurrence of sporadic E are developed, showing percent of time of occurrence in location in the CGL/CGT coordinate system, in terms of sporadic E top frequency (fE sub s) and magnetic activity level. Patterns of E sub s occurrence are related to concepts of the auroral oval, polar cap, and substorms. Sporadic E with top frequency = or> MHz is related to substorms. This sporadic E occurs in the late evening-early night sector of the CGL/CGT coordinate system. Implications of sporadic E on high latitude HF propagation during solar cycle maximum and minimum are discussed. (Author).

The Earth's Magnetic Field : Its History, Origin, and Planetary Perspective

The Dynamical Ionosphere: A Systems Approach to Ionospheric Irregularity examines the Earth's ionosphere as a dynamical system with signatures of complexity. The system is robust in its overall configuration, with smooth space-time patterns of daily, seasonal and Solar Cycle variability, but shows a hierarchy of interactions among its sub-systems, yielding apparent unpredictability, space-time irregularity, and turbulence. This interplay leads to the need for constructing realistic models of the average ionosphere, incorporating the increasing knowledge and predictability of high variability components, and for addressing the difficulty of dealing with the worst cases of ionospheric disturbances, all of which are addressed in this interdisciplinary book. Borrowing tools and techniques from classical and stochastic dynamics, information theory, signal processing, fluid dynamics and turbulence science, The Dynamical Ionosphere presents the state-of-the-art in dealing with irregularity, forecasting ionospheric threats, and theoretical interpretation of various ionospheric configurations. - Presents studies addressing Earth's ionosphere as a complex dynamical system, including irregularities and radio scintillation, ionospheric turbulence, nonlinear time series analysis, space-ionosphere connection, and space-time structures - Utilizes interdisciplinary tools and techniques, such as those associated with stochastic dynamics, information theory, signal processing, fluid dynamics and turbulence science - Offers new data-driven models for different ionospheric variability phenomena - Provides a synoptic view of the state-of-the-art and most updated theoretical interpretation, results and data analysis tools of the "worst case" behavior in ionospheric configurations