Auroral Dynamics and Space Weather


Book Description

The aurora is the most visible manifestation of the connection of the Earth to the space environment and has inspired awe, curiosity, and scientific inquiry for centuries. Recent advances in observing techniques and modeling and theoretical work have revealed new auroral phenomena, provided a better understanding of auroral dynamics, and have led to an enhanced capability for auroral forecasts. This monograph features discussions of: New auroral phenomena due to the ring current ion and polar rain electron precipitation Various auroral forms and hemispheric asymmetry Auroral model development and MHD simulations Application of the auroral observations for radio absorption and scintillation Aurora nowcast and forecast for space weather operations Auroral Dynamics and Space Weather is a valuable contribution for scientists, researchers, space weather operators, and students of Earth's space environment.




Geomagnetism, Aeronomy and Space Weather


Book Description

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




Ionospheric Space Weather


Book Description

This monograph is the outcome of an American Geophysical Union Chapman Conference on longitude and hemispheric dependence of ionospheric space weather, including the impact of waves propagating from the lower atmosphere. The Chapman Conference was held in Africa as a means of focusing attention on an extensive geographic region where observations are critically needed to address some of the fundamental questions of the physical processes driving the ionosphere locally and globally. The compilation of papers from the conference describes the physics of this system and the mechanisms that control ionospheric space weather in a combination of tutorial-like and focused articles that will be of value to the upper atmosphere scientific community in general and to ongoing global magnetosphere-ionosphere-thermosphere (MIT) modeling efforts in particular. A number of articles from each science theme describe details of the physics behind each phenomenon that help to solve the complexity of the MIT system. Because this volume is an outcome of the research presented at this first space science Chapman Conference held in Africa, it has further provided an opportunity for African scientists to communicate their research results with the international community. In addition, the meeting and this conference volume will greatly enhance the space science education and research interest in the African continent and around the world. Ionospheric Space Weather includes articles from six science themes that were discussed at the Chapman Conference in 2012. These include: Hemispherical dependence of magnetospheric energy injection and the thermosphere-ionosphere response Longitude and hemispheric dependence of storm-enhanced densities (SED) Response of the thermosphere and ionosphere to variability in solar radiation Longitude spatial structure in total electron content and electrodynamics Temporal response to lower-atmosphere disturbances Ionospheric irregularities and scintillation Ionospheric Space Weather: Longitude Dependence and Lower Atmosphere Forcing will be useful to both active researchers and advanced graduate students in the field of physics, geophysics, and engineering, especially those who are keen to acquire a global understanding of ionospheric phenomena, including observational information from all longitude sectors across the globe.







Study of Auroral Dynamics with Combined Spacecraft and Incoherent-Scatter Radar Data


Book Description

We have examined Sondrestrom incoherent-scatter radar observations of ionospheric plasma density and temperature distributions, as well as measurements of F-region ion drifts that were made during a prenoon pass by the DMSP-F7 satellite through the radar field of view. The spacecraft traversed a region of intense electron precipitation with a characteristic energy below approximately 200 eV. Particles with such low characteristic energies are believed to originate, either directly or indirectly, in the magnetosheath. The precipitation region had a width of about 2 deg invariant latitude. The corotating radar observed a patch of enhanced electron density and elevated electron temperature in the F2 region between about 10.5 and 12 magnetic local time in the same invariant latitude range where DMSP-F7 detected the soft-electron flux. The ion drift pattern, also obtained by radar, shows that it is unlikely that the plasma patch was produced by solar radiation and advected into the radar field of view. We suggest that the radar observed modifications of the ionospheric plasma distribution, which resulted from direct entry of magnetosheath electrons into the magnetosphere and down to ionospheric altitudes. Model calculations of the ionospheric response to the observed electron flux support our interpretation. Watermann, Juergen Unspecified Center NASW-4063; SRI PROJ. 2781







Space Weather Fundamentals


Book Description

Space weather is one of the most significant natural hazards to human life and health. Conditions of the sun and in the solar wind, magnetosphere, ionosphere, and thermosphere can influence the performance and reliability of space-borne and ground-based technological systems. If conditions in the space environment are adverse, they can cause disruption of satellite operations, communications, navigation, and electric power distribution grids, leading to a variety of socioeconomic losses. This book provides an overview of our current knowledge and theoretical understanding of space weather formation and covers all major topics of this phenomena, from the sun to the Earth’s ionosphere and thermosphere, thus providing a fully updated review of this rapidly advancing field. The book brings together an outstanding team of internationally recognised contributors to cover topics such as solar wind, the earth's magnetic field, radiation belts, the aurora, spacecraft charging, orbital drag and GPS.




Exploring the Secrets of the Aurora


Book Description

This book describes the history of the progress made in auroral science and magnetospheric physics by providing examples of ideas, controversies, struggles, acceptance, and success in some instances. The author, a distinguished auroral scientist, fully describes his experiences in characterizing and explaining auroral phenomena. The volume also includes beautiful full-color photos of the aurora.




Physics of Space Storms


Book Description

This unique , authoritative book introduces and accurately depicts the current state-of-the art in the field of space storms. Professor Koskinen, renowned expert in the field, takes the basic understanding of the system, together with the pyhsics of space plasmas, and produces a treatment of space storms. He combines a solid base describing space physics phenomena with a rigourous theoretical basis. The topics range from the storms in the solar atmosphere through the solar wind, magnetosphere and ionosphere to the production of the storm-related geoelectric field on the ground. The most up-to-date information available ist presented in a clear, analytical and quantitative way. The book is divided into three parts. Part 1 is a phenomenological introduction to space weather from the Sun to the Earth. Part 2 comprehensively presents the fundamental concepts of space plasma physics. It consists of discussions of fundamental concepts of plasma physics, starting from underlying electrodynamics and statistical physics of charged particles and continuing to single particle motion in homogeneous electromagnetic fields, waves in cold plasma approximation, Vlasov theory, magnetohydrodynamics, instabilities in space plasmas, reconnection and dynamo. Part 3 bridges the gap between the fundamental plasma physics and research level physics of space storms. This part discusses radiation and scattering processes, transport and diffiusion, shocks and shock acceleration, storms on the Sun, in the magnetosphere, the coupling to the atmosphere and ground. The book is concluded wtih a brief review of what is known of space stroms on other planets. One tool for building this briege ist extensive cross-referencing between the various chapters. Exercise problems of varying difficulty are embedded within the main body of the text.




Hydrodynamics of Time-Periodic Groundwater Flow


Book Description

Hydrodynamics of Time-Periodic Groundwater Flow introduces the emerging topic of periodic fluctuations in groundwater. While classical hydrology has often focused on steady flow conditions, many systems display periodic behavior due to tidal, seasonal, annual, and human influences. Describing and quantifying subsurface hydraulic responses to these influences may be challenging to those who are unfamiliar with periodically forced groundwater systems. The goal of this volume is to present a clear and accessible mathematical introduction to the basic and advanced theory of time-periodic groundwater flow, which is essential for developing a comprehensive knowledge of groundwater hydraulics and groundwater hydrology. Volume highlights include: Overview of time-periodic forcing of groundwater systems Definition of the Boundary Value Problem for harmonic systems in space and time Examples of 1-, 2-, and 3-dimensional flow in various media Attenuation, delay, and gradients, stationary points and flow stagnation Wave propagation and energy transport Hydrodynamics of Time-Periodic Groundwater Flow presents numerous examples and exercises to reinforce the essential elements of the theoretical development, and thus is eminently well suited for self-directed study by undergraduate and graduate students. This volume will be a valuable resource for professionals in Earth and environmental sciences who develop groundwater models., including in the fields of groundwater hydrology, soil physics, hydrogeology, geoscience, geophysics, and geochemistry. Time-periodic phenomena are also encountered in fields other than groundwater flow, such as electronics, heat transport, and chemical diffusion. Thus, students and professionals in the field of chemistry, electronic engineering, and physics will also find this book useful. Read an interview with the editors to find out more: https://eos.org/editors-vox/a-foundation-for-modeling-time-periodic-groundwater-flow