Download or read book Modeling the Topside Ionosphere and Plasmasphere written by Karl Rawer and published by . This book was released on 2002 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modelling the Topside Ionosphere and Plasmasphere written by COSPAR. Scientific Assembly and published by . This book was released on 2002 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modelling the Topside Ionosphere and Plasmasphere written by D. Bilitza and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book World wide Analysis and Modelling of the Ionospheric and Plasmaspheric Electron Contents by Means of Radio Occultations written by Yixie Shao and published by . This book was released on 2019 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research of this dissertation is studying the ionosphere by GPS radio occultation (RO) techniques. It is mainly divided into two parts. The first part focuses on the methodology in electron density profile retrievals from RO measurements. It aims to get more precise profiles from measured data. Classic Abel inversion is a methodology widely used in RO retrievals, and the error introduced by the spherical symmetry assumption is also well recognised. Separability Method (SM) was developed to eliminate this error in previous studies. In this work, the improvement brought by SM corresponding to classic method is checked and validated. The SM does have better performance excluding the Lack of Collocation (LoC) error. The precision of the results is also shown to depend on the accuracy of the supported GIMs, i.e., the more accurate GIMs are used, the better results can be obtained. The error in SM, introduced by the mis-modelling of using the Vertical Total Electron Content (VTEC) instead of ECLEO, the electron content below LEO height, is also checked. The result shows that it has only minor impact on the retrievals. The second part is the climatological study of topside ionosphere/bottomside plasmasphere based on the RO retrievals using SM, and aims to give a general picture of characteristics and features of these two regions in different solar periods, 2007 -- solar minimum, and 2014 – solar maximum. The empirical two-components models of topside profiles, STIP model and CPDH model, used to separate the ionospheric and plasmaspheric contribution to the VTEC measured from ground to global positioning system (GPS) satellite altitudes, are studied and validated. The conditions of applicability of the STIP model are also discussed. The same as other existing empirical models, it shows the picture of topside ionosphere till some limited altitude, which is decided by the Low Earth Orbit (LEO) satellite height used to observe the RO. The model is used to derive transition height hu and scale height hs during these two years. Generally, hu and hs show the clear diurnal, seasonal, solar cycle dependencies. The concept of IONf, the ionospheric fractional contribution to VTEC, is introduced and studied. The ionospheric features are shown and most of the ionospheric anomalies have been analyzed through this quantity. Compared to the other ionospheric related parameters, such as Ecion and Ecpl, electron content of ionosphere and plasmasphere, IONf is more stable. Hence, it is more suitable for ionosphere modelling. The Capacitor Model is used to model the consistent ‘ionospheric charging process' during the period of the day between sunrise and midday/afternoon. The model shows a good performance to reproduce real data in different circumstances and for the maximum and minimum solar activity years analyzed.
Download or read book Modeling the Ionosphere Thermosphere written by J. D. Huba and published by John Wiley & Sons. This book was released on 2014-03-17 with total page 735 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 201. Modeling the Ionosphere-Thermosphere System brings together for the first time a detailed description of the physics of the IT system in conjunction with numerical techniques to solve the complex system of equations that describe the system, as well as issues of current interest. Volume highlights include discussions of: Physics of the ionosphere and thermosphere IT system, and the numerical methods to solve the basic equations of the IT system The physics and numerical methods to determine the global electrodynamics of the IT system The response of the IT system to forcings from below (i.e., the lower atmosphere) and from above (i.e., the magnetosphere) The physics and numerical methods to model ionospheric irregularities Data assimilation techniques, comparison of model results to data, climate variability studies, and applications to space weather Providing a clear description of the physics of this system in several tutorial-like articles, Modeling the Ionosphere-Thermosphere System is of value to the upper atmosphere science community in general. Chapters describing details of the numerical methods used to solve the equations that describe the IT system make the volume useful to both active researchers in the field and students.
Download or read book Topside Ionosphere and Inner Plasmasphere at Low Solar Flux written by Sevag Derghazarian and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents several detailed observations of the upper portion of the topside ionosphere and inner plasmasphere during low solar flux conditions using Jicamarca's VHF radar. This is followed by theoretical derivations and numerical simulations that aim to present the reader with valuable information and insights into this layer of the upper atmosphere. Measurements of ionospheric parameters are first presented followed by observations of a new class of non-thermal plasma density irregularities that manifest in the equatorial topside ionosphere and inner plasmasphere above Jicamarca in the nighttime and post-midnight sectors. Measurements of ionospheric parameters such as topside density, temperature, ion composition and transition height were acquired during the recent deep solar minimum and correspond to experiments run in October, 2019, February, 2020, and September, 2020. The main features observed are a large and extended decrease in noontime temperatures unlike that seen in studies at moderate solar flux levels, predawn ionospheric heating as early as 0300 LT, large day-to-day variability in the O+/H+ transition height, and negligible helium ion concentration at all altitudes. We also analyze the data in light of the SAMI2-PE model which shows less agreement with the data than at higher solar flux. The main areas of discrepancy with the data are outlined, such as the absence of significant predawn heating, less pronounced decreases in noontime temperatures, and much higher O+ fractions at high altitudes, particularly in September. A discussion is presented on bridging the discrepancies in future model runs. Novel techniques of clutter removal and noise power bias correction are introduced and described in Appendix A. The new class of plasma density irregularities observed in the topside ionosphere and inner plasmasphere in the nighttime and post-midnight sectors are distinct from equatorial spread (ESF) in terms of their morphology and because they exhibit strong spectral sidebands at the lower-hybrid frequency. The coherent echoes were observed in a series high-altitude radar experiments performed at Jicamarca utilizing long- and coded double-pulse modes and a dual-beam mode between the years of 2018 - 2022, overlapping both the deep solar minimum of 2019 - 2020, and a subsequent period of moderately low solar flux. Observations from archival long pulse topside experiments are also presented. Doppler shifts, zonal drifts, and longitudinal dimensions of the echoes are calculated. The coded double-pulse mode was used to measure the low-frequency characteristics of the echoes with fine range resolution. The long-pulse mode was employed for high-frequency spectral analysis which revealed the presence of strong spectral sidelobes at the lower-hybrid frequency. The mechanism underlying lower hybrid waves associated with these lines is subsequently investigated. We present numerical simulations which demonstrate the feasibility of an inverse energy cascade coupled with a short wavelength instability, i.e. the lower hybrid drift instability, in explaining the waves. An inverse cascade is required for short wavelength lower hybrid waves to extend to the 3 m wavelengths measured by the Jicamarca radar. The simulations were able to reproduce multiple features of the measurements.
Download or read book The Earth s Plasmasphere written by Fabien Darrouzet and published by Springer Science & Business Media. This book was released on 2009-08-21 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: James L. Burch·C. Philippe Escoubet Originally published in the journal Space Science Reviews, Volume 145, Nos 1–2, 1–2. DOI: 10. 1007/s11214-009-9532-7 © Springer Science+Business Media B. V. 2009 The IMAGE and CLUSTER spacecraft have revolutionized our understanding of the inner magnetosphere and in particular the plasmasphere. Before launch, the plasmasphere was not a prime objective of the CLUSTER mission. In fact, CLUSTER might not have ever observed this region because a few years before the CLUSTER launch (at the beginning of the 1990s), it was proposed to raise the perigee of the orbit to 8 Earth radii to make multipoint measu- ments in the current disruption region in the tail. Because of ground segment constraints, this proposal did not materialize. In view of the great depth and breadth of plasmaspheric research and numerous papers published on the plasmasphere since the CLUSTER launch, this choice certainly was a judicious one. The fact that the plasmasphere was one of the prime targets in the inner magnetosphere for IMAGE provided a unique opportunity to make great strides using the new and comp- mentary measurements of the two missions. IMAGE, with sensitive EUV cameras, could for the rst time make global images of the plasmasphere and show its great variability d- ing storm-time. CLUSTER, with four-spacecraft, could analyze in situ spatial and temporal structures at the plasmapause that are particularly important in such a dynamic system.
Download or read book The Earth s Plasmasphere written by J. F. Lemaire and published by Cambridge University Press. This book was released on 1998-01-28 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first monograph to describe the historical development of ideas concerning the plasmasphere by the pioneering researchers themselves. The plasmasphere is a cold thermal plasma cloud encircling the Earth, terminating abruptly at a radial distance of 30,000 km over a sharp discontinuity known as the plasmapause. The volume commences with an account of the difficulties met in USSR by Gringauz to publish his early discoveries from Soviet rocket measurements, and the contemporaneous breakthroughs by Carpenter in the USA from ground-based whistler measurements. The authors then update our picture of the plasmasphere by presenting experimental and observational results of the past three decades, and mathematical and physical theories proposed to explain its formation. The volume will be invaluable for researchers in space physics, and will also appeal to those interested in the history of science.
Download or read book Ionospheric Tomography written by Viacheslav E. Kunitsyn and published by Springer Science & Business Media. This book was released on 2003-05-13 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Authored by leading international researchers, this monograph introduces and reviews developed tomograhic methods for discovering 2D and 3D structures of the ionosphere, and discusses the experimental implementation of these methods. The detailed derivations and explanations make this book an excellent starting point for non-specialists.
Download or read book Modeling the F Region of the High Latitude Ionosphere written by W. J. Raitt and published by . This book was released on 1986 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report summarizes work performed in modelling the characteristics of the high/mid latitude ionosphere in two areas; light ion distribution in the plasmasphere under diffusive equilibrium conditions and plasma distribution in the F-region and topside ionosphere in the Southern Hemisphere as a result of the magnetospheric induced convection. In addition there was an attempted experiment on high latitude ionospheric modification. The light ion study showed larger solar cycle and diurnal variations in the plasmaspheric light ion content than observed by whistler measurements. The plasma convection studied predicted more dramatic effects in the gross features of the Southern hemisphere polar region compared to the Northern Hemisphere; this is attributed to the greater offset between the geographic and geomagnetic poles in the Southern Hemisphere. One of the major hemispheric differences observed was the appearance of a dayside trough at certain local lines in the Southern Hemisphere winter. The detection of this feature by ionospheric measurements of 800 km by the DMSP-F4 satellite confirmed the model prediction.
Download or read book Ionospheric Modeling written by KORENKOV and published by Birkhäuser. This book was released on 2013-12-11 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Topside Ionosphere plasmasphere Tomography Using Space borne Dual Frequency GPS Receivers written by Talini S. Pinto Jayawardena and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Specification of the Thickness of the Topside of the Ionosphere written by Richard S. Allen and published by . This book was released on 1975 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model is presented for the thickness of the electron density profile in the region above the F layer maximum. The model varies with time and solar conditions; it is specified by observations or predictions of the height of the F layer maximum; and it is independent of latitude. Results indicate that a mean thickness parameter can be estimated to within about 15 percent and that there is a useful reduction in the day to day variability.
Download or read book Exospheric Models of the Topside Ionosphere written by J. Lemaire and published by . This book was released on 1974 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Magnetospheric Plasma written by T. E. Moore and published by American Geophysical Union. This book was released on 1988 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 44. Existing models of the plasma distribution and dynamics in magnetosphere / ionosphere systems form a patchwork quilt of different techniques and boundaries chosen to define tractable problems. With increasing sophistication in both observational and modeling techniques has come the desire to overcome these limitations and strive for a more unified description of these systems. On the observational side, we have recently acquired routine access to diagnostic information on the lowest energy bulk plasma, completing our view of the plasma and making possible comparisons with magnetohydrodynamic calculations of plasma moments. On the theoretical side, rising computational capabilities and shrewdly designed computational techniques have permitted the first attacks on the global structure of the magnetosphere. Similar advances in the modeling of neutral atmospheric circulation suggest an emergent capability to globally treat the coupling between plasma and neutral gases. Simultaneously, computer simulation has proven to be a very useful tool for understanding magnetospheric behaviors on smaller space and time scales.
Download or read book Ionospheric Modeling written by B. S. Dandekar and published by . This book was released on 1982 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cross Scale Coupling and Energy Transfer in the Magnetosphere Ionosphere Thermosphere System written by Yukitoshi Nishimura and published by Elsevier. This book was released on 2021-12-07 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-Scale Coupling and Energy Transfer in the Magnetosphere-Ionosphere-Thermosphere System provides a systematic understanding of Magnetosphere-Ionosphere-Thermosphere dynamics. Cross-scale coupling has become increasingly important in the Space Physics community. Although large-scale processes can specify the averaged state of the system reasonably well, they cannot accurately describe localized and rapidly varying structures in space in actual events. Such localized and variable structures can be as intense as the large-scale features. This book covers observations on quantifying coupling and energetics and simulation on evaluating impacts of cross-scale processes. It includes an in-depth review and summary of the current status of multi-scale coupling processes, fundamental physics, and concise illustrations and plots that are usable in tutorial presentations and classrooms. Organized by physical quantities in the system, Cross-Scale Coupling and Energy Transfer in the Magnetosphere-Ionosphere-Thermosphere System reviews recent advances in cross-scale coupling and energy transfer processes, making it an important resource for space physicists and researchers working on the magnetosphere, ionosphere, and thermosphere. Describes frontier science and major science around M-I-T coupling, allowing for foundational understanding of this emerging field in space physics Reviews recent and key findings in the cutting-edge of the science Discusses open questions and pathways for understanding how the field is evolving