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Relevant bibliographies by topics / Ionospheric Signatures

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Academic literature on the topic 'Ionospheric Signatures'

Author: Grafiati

Published: 6 September 2023

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Journal articles on the topic "Ionospheric Signatures"

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Wright, D. M., T. K. Yeoman, and J. A. Davies. "A comparison of EISCAT and HF Doppler observations of a ULF wave." Annales Geophysicae 16, no. 10 (1998): 1190–99. http://dx.doi.org/10.1007/s00585-998-1190-7.

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Abstract. Since the middle of 1995, an HF Doppler sounder has been running almost continuously in northern Norway, with the receiver at Ramfjordmoen and the transmitter at Seljelvnes. Concurrent operation of the EISCAT UHF radar in common programme (CP-1) mode has made it possible to study the ionospheric signature of a magnetospheric ULF wave. These are the first results of such wave signatures observed simultaneously in both instruments. It has been demonstrated that the observed Doppler signature was mainly due to the vertical bulk motion of the ionosphere caused by the electric field pertu

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Lockwood, M., and S. K. Morley. "A numerical model of the ionospheric signatures of time-varying magneticreconnection: I. ionospheric convection." Annales Geophysicae 22, no. 1 (2004): 73–91. http://dx.doi.org/10.5194/angeo-22-73-2004.

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Abstract. This paper presents a numerical model for predicting the evolution of the pattern of ionospheric convection in response to general time-dependent magnetic reconnection at the dayside magnetopause and in the cross-tail current sheet of the geomagnetic tail. The model quantifies the concepts of ionospheric flow excitation by Cowley and Lockwood (1992), assuming a uniform spatial distribution of ionospheric conductivity. The model is demonstrated using an example in which travelling reconnection pulses commence near noon and then move across the dayside magnetopause towards both dawn an

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Wright, D. M., T. K. Yeoman, and P. J. Chapman. "High-latitude HF Doppler observations of ULF waves. 1. Waves with large spatial scale sizes." Annales Geophysicae 15, no. 12 (1997): 1548–56. http://dx.doi.org/10.1007/s00585-997-1548-2.

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Abstract. A quantitative study of observations of the ionospheric signatures of magnetospheric ultra low frequency (ULF) waves by a high-latitude (geographic: 69.6°N 19.2°E) high-frequency Doppler sounder has been undertaken. The signatures, which are clearly correlated with pulsations in ground magnetometer data, exhibit periods in the range 100–400 s and have azimuthal wave numbers in the range 3–8. They are interpreted here as local field line resonances. Phase information provided by O- and X-mode Doppler data support the view that these are associated with field line resonances having lar

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Wild, J. A., S. E. Milan, S. W. H. Cowley, et al. "Coordinated interhemispheric SuperDARN radar observations of the ionospheric response to flux transfer events observed by the Cluster spacecraft at the high-latitude magnetopause." Annales Geophysicae 21, no. 8 (2003): 1807–26. http://dx.doi.org/10.5194/angeo-21-1807-2003.

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Abstract. At 10:00 UT on 14 February 2001, the quartet of ESA Cluster spacecraft were approaching the Northern Hemisphere high-latitude magnetopause in the post-noon sector on an outbound trajectory. At this time, the interplanetary magnetic field incident upon the dayside magnetopause was oriented southward and duskward (BZ negative, BY positive), having turned from a northward orientation just over 1 hour earlier. As they neared the magnetopause the magnetic field, electron, and ion sensors on board the Cluster spacecraft observed characteristic field and particle signatures of magnetospheri

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Pryse, S. E., A. M. Smith, I. K. Walker, and L. Kersley. "Multi-instrument study of footprints of magnetopause reconnection in the summer ionosphere." Annales Geophysicae 18, no. 9 (2000): 1118–27. http://dx.doi.org/10.1007/s00585-000-1118-3.

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Abstract. Results are presented from a multi-instrument investigation of the signatures of equatorial reconnection in the summer, sunlit ionosphere. Well-established ion dispersion signatures measured during three DMSP satellite passes were used to identify footprints in ionospheric observations made by radio tomography, and both the EISCAT ESR and mainland radars. Under the prevalent conditions of southward IMF with the Bz component increasing in magnitude, the reconnection footprint was seen to move equatorward through the ESR field-of-view. The most striking signature was in the electron te

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Neudegg, D. A., S. W. H. Cowley, S. E. Milan, et al. "A survey of magnetopause FTEs and associated flow bursts in the polar ionosphere." Annales Geophysicae 18, no. 4 (2000): 416–35. http://dx.doi.org/10.1007/s00585-000-0416-0.

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Abstract. Using the Equator-S spacecraft and SuperDARN HF radars an extensive survey of bursty reconnection at the magnetopause and associated flows in the polar ionosphere has been conducted. Flux transfer event (FTE) signatures were identified in the Equator-S magnetometer data during periods of magnetopause contact in January and February 1998. Assuming the effects of the FTEs propagate to the polar ionosphere as geomagnetic field-aligned-currents and associated Alfvén-waves, appropriate field mappings to the fields-of-view of SuperDARN radars were performed. The radars observed discrete io

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Stocker, A. J., N. F. Arnold, and T. B. Jones. "The synthesis of travelling ionospheric disturbance (TID) signatures in HF radar observations using ray tracing." Annales Geophysicae 18, no. 1 (2000): 56–64. http://dx.doi.org/10.1007/s00585-000-0056-4.

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Abstract. Characteristic signatures are often observed in HF radar range-time-intensity plots when travelling ionospheric disturbances (TIDs) are present. These signatures, in particular the variation of the F-region skip distance, have been synthesised using a ray tracing model. The magnitude of the skip variation is found to be a function of the peak electron density perturbation associated with the TID and radar frequency. Examination of experimental observations leads to an estimate of the peak electron density perturbation amplitude of around 25% for those TIDs observed by the CUTLASS rad

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Thorolfsson, A., J. C. Cerisier, M. Lockwood, P. E. Sandholt, C. Senior, and M. Lester. "Simultaneous optical and radar signatures of poleward-moving auroral forms." Annales Geophysicae 18, no. 9 (2000): 1054–66. http://dx.doi.org/10.1007/s00585-000-1054-2.

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Abstract. Dayside poleward moving auroral forms (PMAFs) were detected between 06:30 and 07:00 UT on December 16, 1998, by the meridian scanning photometer and the all-sky camera at Ny Ålesund, Svalbard. Simultaneous SuperDARN HF radar measurements permitted the study of the associated ionospheric velocity pattern. A good general agreement is observed between the location and movement of velocity enhancements (flow channels) and the PMAFs. Clear signatures of equatorward flow were detected in the vicinity of PMAFs. This flow is believed to be the signature of a return flow outside the reconnect

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Berry, S. T., L. Kersley, J. Moen, and W. F. Denig. "Ionospheric signatures of magnetospheric boundaries in the post-noon sector." Annales Geophysicae 18, no. 1 (2000): 74–80. http://dx.doi.org/10.1007/s00585-000-0074-2.

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Abstract. Spatial structures in ionospheric electron density revealed in a tomographic image have been identified with auroral forms and related to their sources in precipitating particles observed by DMSP satellites. The observations of plasma enhancements relate to discrete auroral arcs seen in the post-noon sector, identified by both red- and green-line emissions measured by a meridional scanning photometer. The features lie within a very narrow latitudinal band on L-shells where the satellite detectors observed electron precipitation classified as from the boundary plasma sheet (BPS). The

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Provan, G., and T. K. Yeoman. "Statistical observations of the MLT, latitude and size of pulsed ionospheric flows with the CUTLASS Finland radar." Annales Geophysicae 17, no. 7 (1999): 855–67. http://dx.doi.org/10.1007/s00585-999-0855-1.

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Abstract. A study has been performed on the occurrence of pulsed ionospheric flows as detected by the CUTLASS Finland HF radar. These flows have been suggested as being created at the ionospheric footprint of newly-reconnected field lines, during episodes of magnetic flux transfer into the terrestrial magnetosphere (flux transfer events or FTEs). Two years of both high-time resolution and normal scan data from the CUTLASS Finland radar have been analysed in order to perform a statistical study of the extent and location of the pulsed ionospheric flows. We note a great similarity between the st

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Dissertations / Theses on the topic "Ionospheric Signatures"

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McWilliams, Kathryn Anne. "Ionospheric signatures of dayside reconnection processes." Thesis, University of Leicester, 2001. http://hdl.handle.net/2381/30652.

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This thesis presents a study of the ionospheric response to dayside magnetopause reconnection. The principal data set employed is the ionospheric convection velocities from the CUTLASS HF radars. In addition to this, images of the ultraviolet aurora from the VIS Earth Camera and the Far Ultraviolet Imager aboard the Polar spacecraft were examined. In situ measurements have shown that there is a time-dependent, periodic nature to magnetic reconnection, with time scales of the order of minutes; the transient nature of magnetopause reconnection is reflected in the ionospheres. In this thesis the

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Borderick, James David. "Ionospheric signatures of ultra low frequency waves." Thesis, University of Leicester, 2011. http://hdl.handle.net/2381/9170.

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Ultra Low Frequency (ULF) waves have been studied for many years and the observation and modelling of such phenomena reveals important information about the solar-terrestrial interaction. Being ubiquitous in the collisionless terrestrial space plasma environment, ULF waves represent important physical processes in the transfer of energy and momentum. This thesis comprises three distinct studies to observe, model and analyse ULF phenomena. The first two studies focus on ULF wave observations at high-latitudes in the terrestrial ionosphere using a collection of both space- and ground-based instr

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Norton, Andrew David. "Analysis of Ionospheric Data Sets to Identify Periodic Signatures Matching Atmospheric Planetary Waves." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/101791.

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Atmospheric planetary waves play a role in introducing variability to the low-latitude ionosphere. To better understand this coupling, this study investigates times when oscillations seen in both atmospheric planetary waves and ionospheric data-sets have similar periodicity. The planetary wave data-set used are temperature observations made by Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). These highlight periods during which 2-Day westward propagating wave-number 3 waves are evident in the mesosphere and lower thermosphere. The ionospheric data-set is Total Electron C

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Schlatter, Nicola. "Radar Signatures of Auroral Plasma Instability." Doctoral thesis, KTH, Rymd- och plasmafysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160894.

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Incoherent scatter radars are powerful ground based instruments for ionospheric measurements. By analysis of the Doppler shifted backscatter spectrum, containing the signature of electrostatic plasma waves, plasma bulk properties are estimated. At high latitudes the backscattered radar power is occasionally enhanced several orders of magnitude above the thermal backscatter level. These enhancements occur during geomagnetic disturbed conditions and are referred to as naturally enhanced ion acoustic echoes (NEIALs). NEIALs are linked to auroral activity with optical auroral emission observed in

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Aminaei, Amin. "Characteristics of night time absorption spike events as signatures of magnetosphere ionosphere (M-I) coupling." Thesis, Lancaster University, 2007. http://eprints.lancs.ac.uk/6764/.

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Night time absorption spike events (NASE) are common signatures of magnetospheric substorms. Their occurrence in the ionosphere can be easily detected by riometers located at ground based stations. This unique feature is used to achieve a comprehensive study based on 500 NASE occurred during the period 1994-2003 in the IRIS (imaging riometer for ionospheric studies) field of view at Kilpisjarvi, Finland centred at 69.05Ã‚Â° N, 20.79Ã‚Â° E (L-shell 6.1). NASE generally had similar behaviour which has been mentioned for substorms in the literature. Occurrence of NASE dominates around magnetic lo

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Koen, Etienne Johannes. "Ionospheric signatures of solar flares." Thesis, 2009. http://hdl.handle.net/10413/8339.

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VLF waves propagate in the Earth-ionosphere waveguide (EIW). The EIW is bounded below by the surface of the Earth and above by the ionospheric D-region (50–90 km altitude). The conditions for wave propagation in the EIW are studied and derived specifically for VLF propagation. The D-region is maintained by shortwave solar radiation that ionises the neutral atmosphere. The Wait parameters, H′ (reflection height) and (sharpness), describe the lower boundary of the D-region. Any enhancement in solar X-rays modifies these parameters, leading to a change in the propagation conditions for VLF sign

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FU-YUAN, CHANG, and 張富淵. "A Study on Ionospheric Neutral Wind Signatures by Using FORMOSAT-3/COSMIC." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/76chw3.

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博士<br>國立中央大學<br>太空科學研究所<br>105<br>The Earth’s upper atmosphere, comprised of the thermosphere and ionosphere, is where neutral and charged particles interact causing complicated physical processes. The ionospheric electron density is highly variable with the altitude, latitude, longitude, local time, season, solar cycle. This dissertation shows the investigation of the nighttime features from the coupling between the ionosphere and thermospheric neutral wind. Two interesting phenomena associated with the electrodynamic processes are examined, which include (1) The Weddell Sea Anomaly (WSA

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Law, Colin Christian. "Observations of magnetic signatures and structure in the dayside ionosphere of Venus." Thesis, 1993. http://hdl.handle.net/1911/13753.

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Present models of the Venus solar wind interaction do not allow for changes in the orientation of the field as you approach the planet. Analysis of high resolution magnetic field data from the Pioneer Venus Orbiter spacecraft has revealed two distinct field rotations that are observed to occur in conjunction with the dayside ionosphere and ionopause. These rotations are a result of the velocity shear at the ionopause and indicate an alignment of the magnetic field with the day to night ionospheric plasma flow. From these results a new configuration of the dayside field draping has been determi

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Books on the topic "Ionospheric Signatures"

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Rice University. Space Physics and Astronomy Dept. and United States. National Aeronautics and Space Administration., eds. Final report, entitled, Data reduction and analysis of Pioneer Venus Orbital Ion Mass Spectrometer: NASA grant NAG 2-566, covering the period October 1998 - March 1996. Space Physics and Astronomy Dept., Rice University, 1996.

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Book chapters on the topic "Ionospheric Signatures"

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Newell, Patrick T., and David G. Sibeck. "Magnetosheath Fluctuations, Ionospheric Convection and Dayside Ionospheric Transients." In Physical Signatures of Magnetospheric Boundary Layer Processes. Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1052-5_17.

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Rodger, A. S. "Ionospheric Signatures of Magnetopause Processes." In Polar Cap Boundary Phenomena. Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-5214-3_10.

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Lockwood, M. "Ionospheric Signatures of Pulsed Magnetopause Reconnection." In Physical Signatures of Magnetospheric Boundary Layer Processes. Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1052-5_16.

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Friis-Christensen, E. "Terrestrial ionospheric signatures of field-aligned currents." In Physics of Magnetic Flux Ropes. American Geophysical Union, 1990. http://dx.doi.org/10.1029/gm058p0605.

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Fenrich, F. R., C. L. Waters, M. Connors, and C. Bredeson. "Ionospheric signatures of ULF waves: Passive radar techniques." In Magnetospheric ULF Waves: Synthesis and New Directions. American Geophysical Union, 2006. http://dx.doi.org/10.1029/169gm17.

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Yeoman, T. K., D. M. Wright, and L. J. Baddeley. "Ionospheric signatures of ULF waves: Active radar techniques." In Magnetospheric ULF Waves: Synthesis and New Directions. American Geophysical Union, 2006. http://dx.doi.org/10.1029/169gm18.

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Knipp, D. J., B. A. Emery, and G. Lu. "Application of the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) Procedure to CUSP Identification." In Physical Signatures of Magnetospheric Boundary Layer Processes. Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1052-5_28.

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Watanabe, Masakazu, Michael Pinnock, Alan S. Rodger, et al. "Ionospheric Signatures of Distant Tail Reconnection Observed Just Before Substorm Onsets." In Substorms-4. Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4798-9_150.

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Lognonné, P. "Seismic Waves from Atmospheric Sources and Atmospheric/Ionospheric Signatures of Seismic Waves." In Infrasound Monitoring for Atmospheric Studies. Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-1-4020-9508-5_10.

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Olsen, Nils, and Claudia Stolle. "Magnetic Signatures of Ionospheric and Magnetospheric Current Systems During Geomagnetic Quiet Conditions—An Overview." In Earth's Magnetic Field. Springer Netherlands, 2017. http://dx.doi.org/10.1007/978-94-024-1225-3_2.

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Conference papers on the topic "Ionospheric Signatures"

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Maheswaran, Veera Kumar, James A. Baskaradas, and Sriram Subramanian. "GNSS/GPS Spoofing Detection using Ionospheric Signatures." In 2021 IEEE Indian Conference on Antennas and Propagation (InCAP). IEEE, 2021. http://dx.doi.org/10.1109/incap52216.2021.9726378.

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Vorobjev, Vyacheslav, and Vladimir Zverev. "Dayside aurora signatures associated with ionospheric travelling twin vortices." In High Latitude Optics, edited by Sergej Leontyev. SPIE, 1993. http://dx.doi.org/10.1117/12.164828.

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Fasel, G. J., Joseph I. Minow, Roger W. Smith, C. S. Deehr, and Lou-Chuang Lee. "Ionospheric signatures of solar-wind magnetosphere interaction in dayside aurora." In High Latitude Optics, edited by Sergej Leontyev. SPIE, 1993. http://dx.doi.org/10.1117/12.164827.

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Almeida, P. D. S. C., C. M. Denardini, H. C. Aveiro, L. C. A. Resende, and L. M. Guizelli. "ANALYSIS OF SOLAR TIDAL SIGNATURES IN IONOSPHERIC ELECTRIC CURRENTS OBSERVED BY MAGNETOMETERS." In 11th International Congress of the Brazilian Geophysical Society & EXPOGEF 2009, Salvador, Bahia, Brazil, 24-28 August 2009. Society of Exploration Geophysicists and Brazilian Geophysical Society, 2009. http://dx.doi.org/10.1190/sbgf2009-030.

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Almeida, P. D. S. C., C. M. Denardini, H. C. Aveiro, L. C. A. Resende, and L. M. Guizelli. "Analysis Of Solar Tidal Signatures In Ionospheric Electric Currents Observed By Magnetometers." In 11th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 2009. http://dx.doi.org/10.3997/2214-4609-pdb.195.1841_evt_6year_2009.

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Hughes, David H. "Modeling the diurnal variation of ionospheric layers via Thom canonical potentials: time-frequency signatures." In International Symposium on Optical Science and Technology, edited by Franklin T. Luk. SPIE, 2002. http://dx.doi.org/10.1117/12.447888.

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Jansky, Jaroslav, and Victor Pasko. "Charge balance, electric field and ionospheric potential signatures in time dependent global electric circuit model." In 2014 XXXIth URSI General Assembly and Scientific Symposium (URSI GASS). IEEE, 2014. http://dx.doi.org/10.1109/ursigass.2014.6929973.

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Heitmann, Andrew J., Manuel A. Cervera, Robert S. Gardiner-Garden, et al. "Observations and modeling of traveling ionospheric disturbance signatures from an Australian network of oblique angle-of-arrival sounders." In 2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS). IEEE, 2017. http://dx.doi.org/10.23919/ursigass.2017.8105329.

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Maurya, Ajeet K., Rajesh Singh, Sushil Kumar, D. V. Phani Kumar, and B. Veenadhari. "Waves-like signatures in the D-region ionosphere generated by solar flares." In 2014 XXXIth URSI General Assembly and Scientific Symposium (URSI GASS). IEEE, 2014. http://dx.doi.org/10.1109/ursigass.2014.6929796.

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Yue, Wenjue, Bo Peng, Xizhang Wei, and Xiang Li. "Ionosphere effect estimation in micro-Doppler signature extraction for P-band radar targets." In 2017 Progress In Electromagnetics Research Symposium - Spring (PIERS). IEEE, 2017. http://dx.doi.org/10.1109/piers.2017.8262052.

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Reports on the topic "Ionospheric Signatures"

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Fox, Matthew W., Xiaoqing Pi, and Jeffrey M. Forbes. First Principles and Applications-Oriented Ionospheric Modeling Studies, and Wave Signatures in Upper Atmosphere Density,. Defense Technical Information Center, 1997. http://dx.doi.org/10.21236/ada325072.

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Dea, J. Y., W. Van Bise, E. A. Rauscher, and W. M. Boerner. Observations of ELF Signatures Arising from Space Vehicle Disturbances of the Ionosphere. Defense Technical Information Center, 1991. http://dx.doi.org/10.21236/ada236563.

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