Download or read book GPS Total Electron Content Techniques for Observing the Structure and Dynamics of the High Latitude Ionosphere written by Chris Watson and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The solar wind, magnetosphere and ionosphere (SW-M-I) constitute a highly coupled system, where solar wind energy drives dynamic processes of the magnetospheric cavity and embedded ionosphere. The high latitude ionosphere has an inherently complex structure and dynamic behavior due to direct coupling to the solar wind and outer magnetosphere. Energy and charged particles deposited in the high latitude ionosphere via SW-M-I coupling processes generate ionization structures with variable spatial scales and dynamic behavior. Characteristics of ionization structures, such as their source, generation mechanisms, and evolution, are not well understood, largely due to past inadequacies in observational capabilities at high latitudes. From a physics perspective, the observation of high latitude ionospheric processes and structures is a proven technique for studying physical processes in the magnetosphere and solar wind. From an industrial and societal perspective, the dynamic high latitude ionosphere is potentially problematic due to significant impacts on electromagnetic signals used for navigation and communication. Recent installation of high data rate Global Positioning System (GPS) receivers of the Canadian High Arctic Ionospheric Network (CHAIN) has provided new, high resolution observations of the high latitude ionosphere. This thesis uses a statistical study and case studies to investigate the characteristics and source regions of ionospheric total electron content (TEC) variations observed by CHAIN GPS receivers. In the statistical study, occurrence rate, amplitude, and frequency of TEC variations were examined, in order to investigate the dependence of these characteristics on magnetic local time, latitude, and solar wind conditions. In three case studies, variations in TEC resulting from ultra-low frequency (ULF) waves in Earth’s geomagnetic field were observed. It is shown that GPS TEC has a significant response to various ULF wave classifications and intensities, and is a potentially valuable tool for high resolution study of ULF activity and the associated ionospheric response.
Download or read book Variability of Total Electron Content in the High Latitude Ionosphere Following Solar Maximum written by and published by . This book was released on 1995 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: A data archive of Total Electron Content CIEC) data was developed through operation and maintenance of GPS satellite receiver equipment at Shemya, AK; Hanscom AFB, MA; Thule AB, Greenland; Tucuman, Argentina; and Agua Verde, Chile. Scintillation data can be extracted ftom much of this database. The Shemya, AK, data provide a valuable source for characterizing TEC morphology and variability with look direction at this site. The Shemya data were also used in an initial assessment of the seasonal and directional specification accuracy of the Bent ionospheric model, specific to this site. Analysis of an existing NWRA database has produced ionospheric trough boundary signatures in the sub auroral European sector. These signatures will support studies aimed at real time detection of the trough boundary. Innovative software techniques were developed to improve data quality in the areas of multipath rnitigation (the Multipath Template Technique) and the automated calibration of an installed receiver system for the combination of all system components' contributions to pseudorange error (SCORE:: Self-Calibration Of pseudoRange Errors).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Space Physics and Aeronomy Ionosphere Dynamics and Applications written by Chao Huang and published by John Wiley & Sons. This book was released on 2021-05-11 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive review of global ionospheric research from the polar caps to equatorial regions It's more than a century since scientists first identified the ionosphere, the layer of the Earth’s upper atmosphere that is ionized by solar and cosmic radiation. Our understanding of this dynamic part of the near-Earth space environment has greatly advanced in recent years thanks to new observational technologies, improved numerical models, and powerful computing capabilities. Ionosphere Dynamics and Applications provides a comprehensive overview of historic developments, recent advances, and future directions in ionospheric research. Volume highlights include: Behavior of the ionosphere in different regions from the poles to the equator Distinct characteristics of the high-, mid-, and low-latitude ionosphere Observational results from ground- and space-based instruments Ionospheric impacts on radio signals and satellite operations How earthquakes and tsunamis on Earth cause disturbances in the ionosphere The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals. Find out more about the Space Physics and Aeronomy collection in this Q&A with the Editors in Chief
Download or read book An Algorithm for Accurate Ionospheric Total Electron Content and Receiver Bias Estimation Using GPS Measurements written by Harrison W Bourne and published by . This book was released on 2016 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : The ionospheric total electron content (TEC) is the integrated electron density across a unit area. TEC is an important property of the ionosphere. Accurate estimation of TEC and TEC spatial distributions are needed for many space-based applications such as precise positioning, navigation, and timing. The Global Positioning System (GPS) provides one of the most versatile methods for measuring the ionosphere TEC, as it has global coverage, high temporal resolution, and relatively high spatial resolution. The objective of this thesis is to develop an algorithm for accurate estimation of the TEC using dual-frequency GPS receiver measurements and simultaneously estimate the receiver hardware bias in order to mitigate its effect on the TEC. This method assumes the TEC in the portion of sky visible to the receiver can be represented as a two dimensional sheet with an absolute value and spacial gradients with respect to latitude and longitude. A code-phase multipath noise estimation algorithm is integrated with the TEC estimation process to mitigate environmental multipath contamination of the measurements. The integrated algorithm produces an approximate map of local TEC using a single dual-frequency receiver while minimizing both multipath induced errors and the receiver hardware bias. The goal of this method is to provide an accurate map of the ionosphere TEC, in the region local to the receiver, without the need for a network of receivers and in the absence of knowledge of the receiver hardware induced bias. This thesis describes the algorithm, its implementation, and attempts to validate the method through comparison with incoherent scatter radar (ISR) data from low, mid, and high latitude locations.
Download or read book Ionospheric Space Weather written by Timothy Fuller-Rowell and published by John Wiley & Sons. This book was released on 2016-12-05 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Ionosphere New Perspectives written by Yann-Henri Chemin and published by BoD – Books on Demand. This book was released on 2023-06-21 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ionosphere is a layer of the Earth's atmosphere that extends from about 50 km to 1000 km above the Earth's surface. It is ionized by solar radiation, which creates ions and free electrons in the upper atmosphere. These ions and electrons reflect radio waves back to the Earth's surface, allowing long-distance radio communication as well as absorption of harmful solar radiation. Ionospheric conductivity monitoring assesses the state of the ionosphere and improves the accuracy of satellite communications. This book is organized into two sections on the influence and impact of transient or orbiting humanmade objects into the ionosphere and the monitoring and modeling of the temporal evolution of the ionosphere. The information presented will lead to a better understanding and forecasting of the ionosphere’s dynamic.
Download or read book Ionospheric Tomography written by Viacheslav E. Kunitsyn and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 263 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 Prediction of Total Electron Content Using the International Reference Ionosphere written by L. F. McNamara and published by . This book was released on 1983 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Reference Ionosphere (IRI) is a model of the ionosphere, based on experimental data, that has been proposed as a standard ionospheric model. As such, it should be tested extensively to determine its range of validity. One of the ways in which the electron density profile given by the IRI, especially above the peak of the F layer, can be tested is to compare calculated and observed values of total electron content (TEC). We have therefore studied the discrepancies between calculated and observed values of TEC recorded at 15 stations covering a wide range of longitudes and latitudes mainly in the northern hemisphere, and mainly for high levels of solar activity. We have found that the IRI produces reasonably accurate values of TEC at mid- and high-latitudes, but that if greatly underestimates the daytime values of TEC at low latitudes. We conclude therefore that the daytime electron density profile given by the IRI is reasonably accurate at mid- and high-latitudes; at least above the peak of the F2 layer. The situation at low latitudes clearly requires more work, and we have suggested two possible lines of study. The generally low discrepancies at night indicate that the nighttime electron density profiles given by the IRI correspond fairly closely to the actual profiles.
Download or read book Handbook of Geophysics and Space Environments written by U.S. Air Force Geophysics Laboratory and published by . This book was released on 1985 with total page 1066 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book GPS TEC and Riometer Techniques for Observing Absorption Events in the High Latitude Ionosphere written by Chris Watson and published by . This book was released on 2011 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Meteorological and Geoastrophysical Abstracts written by and published by . This book was released on 1997 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mapping and Predicting the Earth s Ionosphere Using the Global Positioning System written by Stefan Schaer and published by . This book was released on 1999-01-01 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Latitude Measurements of the Total Electron Content TEC Using the Faraday Technique and Comparisons with TEC Estimates from NAVSTAR GPS Data written by Kaare Aksnes and published by . This book was released on 1981 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: A VHF electronic polarimeter for total electron content (TEC) measurements has been in operation at Troms0 Telemetry Station (69 deg 39'N, 18 deg 56'E) in Northern Norway for the period April 1980 to April 1981. The polarimeter has been receiving data from the geostationary satellite SIRIO, which is situated almost due south of Troms0 at 8 deg elevation. Except for loss of data during periods when the satellite was eclipsed by the Earth's shadow, continuous data coverage was maintained. Preliminary analysis of the obtained TEC data and similar data deduced from NAVSTAR-GPS measurements reveal acceptable agreement. (Author).
Download or read book A Study of Ionospheric F2 Layer Frequency and Gps Total Electron Content written by Muhammad Ayyaz Ameen and published by LAP Lambert Academic Publishing. This book was released on 2012-07 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the study of relationship between the Total Electron Content (TEC) derived from a Global Positioning System (GPS) receiver and the critical frequency of the F2-layer of the ionosphere in the Equatorial Ionization Anomaly (EIA) region. A practical problem of devising a method to use GPS TEC as a proxy of foF2 was considered for Vanimo, (Papua New Guinea). The study was carried out successfully for southern and northern hemisphere EIA stations. The International Reference Ionosphere (IRI) and electron density profiler NeQuick models were used and the observations were compared with the model outputs. A successive iteration process was applied using the NeQuick model which restricted the TEC to 5% of the GPS TEC value but this could only yield 56% of the foF2 values within a tolerance of 1MHz. A slab thickness model was also used to get the desired output which resulted in 25% success only. The main features of the equatorial anomaly were obtained and verified from both the observed and model datasets. Another dataset from MIT was also used to compare high and low solar activity conditions"
Download or read book Solar and Space Physics written by National Research Council and published by National Academies Press. This book was released on 2014-09-25 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2010, NASA and the National Science Foundation asked the National Research Council to assemble a committee of experts to develop an integrated national strategy that would guide agency investments in solar and space physics for the years 2013-2022. That strategy, the result of nearly 2 years of effort by the survey committee, which worked with more than 100 scientists and engineers on eight supporting study panels, is presented in the 2013 publication, Solar and Space Physics: A Science for a Technological Society. This booklet, designed to be accessible to a broader audience of policymakers and the interested public, summarizes the content of that report.
Download or read book Aeronomy of the Earth s Atmosphere and Ionosphere written by Mangalathayil Ali Abdu and published by Springer Science & Business Media. This book was released on 2011-02-26 with total page 479 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
