Download or read book An Ionospheric Model for the Arctic written by George J. Gassmann and published by . This book was released on 1970 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: A first order approximation model of the Arctic ionosphere is described, based on published observations and concepts. The model allows for modifications and additions whenever new information becomes available, and will eventually represent a true picture available in real time or even as forecast. The location of the phenomena is specified in corrected geomagnetic latitude and local time. Various input parameters are included whenever some of their influences are known, such as UT, seasons, sunspot number, magnetic variations. The Arctic ionospheric features are specified as 'quasi-instant' deviations from routine predictions whereby the devitations represent probabilities of occurrence during periods that may range from 20 min to 3 hr. The following ionospheric features are more or less covered: auroral E (or night-E), auroral Es (or Esr), HF absorption, Arctic F. Necessary improvements to the model are indicated, including the inclusion of storm-time of individual substorms and the requirement that routine observations be maintained in the midnight sector of the auroral oval. (Author).
Download or read book An Ionospheric Model for the Arctic written by George J. Gassmann and published by . This book was released on 1970 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A first order approximation model of the Arctic ionosphere is described, based on published observations and concepts. The model allows for modifications and additions whenever new information becomes available, and will eventually represent a true picture available in real time or even as forecast. The location of the phenomena is specified in corrected geomagnetic latitude and local time. Various input parameters are included whenever some of their influences are known, such as UT, seasons, sunspot number, magnetic variations. The Arctic ionospheric features are specified as 'quasi-instant' deviations from routine predictions whereby the devitations represent probabilities of occurrence during periods that may range from 20 min to 3 hr. The following ionospheric features are more or less covered: auroral E (or night-E), auroral Es (or Esr), HF absorption, Arctic F. Necessary improvements to the model are indicated, including the inclusion of storm-time of individual substorms and the requirement that routine observations be maintained in the midnight sector of the auroral oval. (Author)
Download or read book Arctic Ionosphere and Aurora written by J. Buchau and published by . This book was released on 1970 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: In response to Air Force needs for specifying and forecasting conditions of the Arctic ionosphere, AFCRL's Airborne Ionospheric Laboratory, a highly instrumented NKC 135 jet aircraft, was used in an extensive Arctic research program that started in 1967. To date, 69 flights were made and ionospheric and optical data covering major parts of the auroral oval, mainly the midday sector and the night sector, were collected. During the winter months of 1967, 1968, 1969, and 1970 special emphasis was put on the investigation of the day sector. These flights covered a rather unique and poorly investigated area of the auroral oval, and a detailed report on the observations is given here. A thorough analysis of the data collected in the day sector reveals the existence of a band of continuous particle precipitation south of the location of the discrete aurora. This precipitation hardens towards the south and results in E- and D-region ionization. These observations compare very well with measurements of precipitating particles done by satellite. The investigation of the evening and night sectors showed similar but less organized trends than on the day side. During several flights the continuity of the auroral oval was verified. The investigation indicates that, with additional measurements, it may be possible to develop a model of the Arctic ionosphere. With control measurements from a few ideally located ground stations, the dynamics of the Arctic ionosphere might then be utilized for forecasting propagation conditions in the Arctic. (Author).
Download or read book The Empirical Canadian High Arctic Ionospheric Model E CHAIM written by David R. Themens and published by . This book was released on 2018 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This phase of the E-CHAIM project involved the validation and testing of the model in preparation for final release. For this purpose, we first examined the performance of the model under the most extreme conditions one could expect it to operate (intermediate timescales)"--Abstract.
Download or read book Analog Model 1972 of the Arctic Ionosphere written by G. J. Gassmann and published by . This book was released on 1973 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report supplements earlier attempts at modelling. Its elements are the result of a group effort, which is continuing. The arctic ionosphere and its dynamics are described as a fairly self-consistent empirical quasi-instantaneous model, adaptable to later improvements. The definitions are in analog form using model, adaptable to later improvements. The definitions are in analog form using tables, graphs, and analytical formulas. The model parameters controlling the arctic ionosphere are substorm time and intensity and oval number Q. Emphasis is given as to how those parameters may be obtained in near-real-time. For this purpose, two superimposed coordinate systems and two reference latitudes are introduced. The model assumes absence of sunlight; it provides rules for adding the sunlit contribution and for matching the arctic model to the moderate-latitude ionosphere. (Author).
Download or read book An Empirical Model of the Polar Ionosphere written by Terence James Elkins and published by . This book was released on 1973 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Four separate articles are collected which deal with the construction of empirical models of the polar ionosphere. The particular emphasis in these articles is towards the radio propagation application of the models. Numerical models of the vertical electron density profiles on the topside and bottomside of the F-region are developed, and a model for sporadic-E is included. Special attention is devoted to features which are characteristic of the polar ionosphere-auroral effects, the trough, and magnetospheric cleft regions. The models are constructed specifically for convenience in computer programming, and in fact, all aspects of the models contained in this report are available in the form of Fortran computer programs. (Author).
Download or read book Arctic Ionosphere Modelling written by George J. Gassmann and published by . This book was released on 1972 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: ;Contents: Instantaneous versus averaged ionosphere; Modelling the auroral E-layer; Model of arctic sporadic E; Modelling the arctic F-layer; Coordinate conversion and other computer programs for arctic ionospheric research.
Download or read book The Height of F layer Irregularities in the Arctic Ionosphere written by Howard Francis Bates and published by . This book was released on 1959 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Airborne Determination of Arctic Ionosphere Cross Sections written by George J. Gassmann and published by . This book was released on 1972 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: From 3 to 20 June 1972 the airborne ionospheric laboratory was stationed in RAF Mildenhall, England, for the purpose of obtaining realistic ionization cross-sections suitable for assessing HF propagation conditions in the Arctic. A number of quasi-instantaneous cross-sections for various hours during local night of five different days were produced, however limited to low magnetic activity, except for one PCA event, and limited to the area north of England. The results provide a three dimensional representation of the ionosphere along a 7 degree wide azimuth range. (Author).
Download or read book Numerical Modeling of Polar Ionospheric Electrodynamics for July 23 24 1983 Utilizing Ionospheric Conductances Deduced from DMSP X ray Images written by and published by . This book was released on 1988 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Improvement of polar zone ionospheric model written by H. Thiemann and published by . This book was released on 1990 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Detailed Specification of the Arctic Ionosphere and an Application to Three dimensional Raytracing written by J. Buchau and published by . This book was released on 1973 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A statistical analysis of Alouette topside ionograms shows that the probability of occurrence of the midlatitude F-layer trough is 100 percent in winter and at equinox, and is 50 percent in summer. The trough, which is generally centered on 55 degrees corrected geomagnetic latitude and which is about 5 degrees to 10 degrees wide, extends throughout the night hemisphere with f(o)F2 values less than 2 MHz. Comparison of the location of the trough to the area in which coverage by an over the horizon backscatter (OTHB) system is anticipated shows that the trough will adversely affect system performance in the northeast direction most of the night. An in-depth case study of the effects of the trough on HF propagation was made, based on an instantaneous three-dimensional description of the ionosphere. This description of the ionosphere was composed of cross sections showing ionospheric electron-density structure in the area northeast of the Polar Fox II site. Three-dimensional raytracing was applied to this description of the ionosphere, and the trough and the steep electron-density gradient at the poleward edge of the trough were found to adversely affect propagation of HF signals. (Modified author abstract).
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 A Computer Model of the Polar F region Ionosphere written by Brenton John Watkins and published by . This book was released on 1976 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analog Model 1972 of the Arctic Ionosphere written by G. L. Gassmann and published by . This book was released on 1973 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report supplements earlier attempts at modelling. Its elements are the result of a group effort, which is continuing. The arctic ionosphere and its dynamics are described as a fairly self-consistent empirical quasi-instantaneous model, adaptable to later improvements. The definitions are in analog form using model, adaptable to later improvements. The definitions are in analog form using tables, graphs, and analytical formulas. The model parameters controlling the arctic ionosphere are substorm time and intensity and oval number Q. Emphasis is given as to how those parameters may be obtained in near-real-time. For this purpose, two superimposed coordinate systems and two reference latitudes are introduced. The model assumes absence of sunlight; it provides rules for adding the sunlit contribution and for matching the arctic model to the moderate-latitude ionosphere. (Author).
Download or read book Analog Model 1972 of the Arctic Ionosphere written by George J. Gassmann and published by . This book was released on 1973 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report supplements earlier attempts at modelling. Its elements are the result of a group effort, which is continuing. The arctic ionosphere and its dynamics are described as a fairly self-consistent empirical quasi-instantaneous model, adaptable to later improvements. The definitions are in analog form using model, adaptable to later improvements. The definitions are in analog form using tables, graphs, and analytical formulas. The model parameters controlling the arctic ionosphere are substorm time and intensity and oval number Q. Emphasis is given as to how those parameters may be obtained in near-real-time. For this purpose, two superimposed coordinate systems and two reference latitudes are introduced. The model assumes absence of sunlight; it provides rules for adding the sunlit contribution and for matching the arctic model to the moderate-latitude ionosphere. (Author)
Download or read book Arctic Communications written by B. Landmark and published by Elsevier. This book was released on 2013-10-22 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic Communications is a compilation of the proceedings of the Eighth Meeting of the Ionospheric Research Committee of NATO's Advisory Group for Aeronautical Research and Development, held in Athens, Greece in July 1963. The meeting provided a forum for discussing advances in communications equipment used to conduct research in the Arctic and covered a wide range of topics such as the physical properties of the Arctic ionosphere; Arctic high-frequency communications; soundings and field strength measurements; and observations in the Arctic during nuclear tests. This book is comprised of 25 chapters and begins with a discussion on experimental studies of high latitude absorption phenomena, including auroral absorption, polar cap absorption, and sudden commencement absorption. Direct measurements of D-region electron densities during the absorption periods are also presented. Subsequent chapters focus on the ionospheric absorption of cosmic noise observed at geomagnetically conjugate points; ionospheric ionization produced by solar flares; military communication facilities in the Canadian Arctic; and radio noise problems in Arctic regions. Phase instabilities on a very-low-frequency transmission path passing through the auroral zone are also considered. This monograph will be of particular value to scientists and researchers with interest in the Arctic.
