World Library  


Add to Book Shelf
Flag as Inappropriate
Email this Book

Towards a Synthesis of Substorm Electrodynamics: Hf Radar and Auroral Observations : Volume 24, Issue 12 (21/12/2006)

By Grocott, A.

Click here to view

Book Id: WPLBN0004001410
Format Type: PDF Article :
File Size: Pages 17
Reproduction Date: 2015

Title: Towards a Synthesis of Substorm Electrodynamics: Hf Radar and Auroral Observations : Volume 24, Issue 12 (21/12/2006)  
Author: Grocott, A.
Volume: Vol. 24, Issue 12
Language: English
Subject: Science, Annales, Geophysicae
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Historic
Publication Date:
2006
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications

Citation

APA MLA Chicago

Devlin, J. C., Parkinson, M. L., Yeoman, T. K., Lester, M., Dyson, P. L., Grocott, A., & Frey, H. U. (2006). Towards a Synthesis of Substorm Electrodynamics: Hf Radar and Auroral Observations : Volume 24, Issue 12 (21/12/2006). Retrieved from http://worldebookfair.com/


Description
Description: Department of Physics {&} Astronomy, University of Leicester, Leicester LE1 7RH, UK. At 08:35 UT on 21 November 2004, the onset of an interval of substorm activity was captured in the southern hemisphere by the Far UltraViolet (FUV) instrument on board the IMAGE spacecraft. This was accompanied by the onset of Pi2 activity and subsequent magnetic bays, evident in ground magnetic data from both hemispheres. Further intensifications were then observed in both the auroral and ground magnetic data over the following ~3 h. During this interval the fields-of-view of the two southern hemisphere Tasman International Geospace Enviroment Radars (TIGER) moved through the evening sector towards midnight. Whilst initially low, the amount of backscatter from TIGER increased considerably during the early stages of the expansion phase such that by ~09:20 UT an enhanced dusk flow cell was clearly evident. During the expansion phase the equatorward portion of this flow cell developed into a narrow high-speed flow channel, indicative of the auroral and sub-auroral flows identified in previous studies (e.g. Freeman et al., 1992; Parkinson et al., 2003). At the same time, higher latitude transient flow features were observed and as the interval progressed the flow reversal region and Harang discontinuity became very well defined. Overall, this study has enabled the spatial and temporal development of many different elements of the substorm process to be resolved and placed within a simple conceptual framework of magnetospheric convection. Specifically, the detailed observations of ionospheric flows have illustrated the complex interplay between substorm electric fields and associated auroral dynamics. They have helped define the distinct nature of different substorm current systems such as the traditional substorm current wedge and the more equatorward currents associated with polarisation electric fields. Additionally, they have revealed a radar signature of nightside reconnection which provides the promise of quantifying nightside reconnection in a way which has already proved extremely successful in studies of the dayside magnetosphere.

Summary
Towards a synthesis of substorm electrodynamics: HF radar and auroral observations

Excerpt
Akasofu,~S.-I.: The dynamical morphology of the auroral polaris, J Geophys. Res., 68, 1667–1672, 1963.; Akasofu,~S.-I.: The development of the auroral substorm, Planet. Space Sci., 12, 273–282, 1964.; Akasofu,~S.-I.: Polar and magnetospheric substorms, Dordrecht: Reidel, 1968.; Akasofu, ~S I.: Physics of magnetospheric substorms, Dordrecht: Reidel, 1977.; Akasofu,~S.-I., Chapman,~S., and Meng,~C.-I.: The polar electrojet, J. Atmos. Terr. Phys., 27, 1275–1305, 1965.; Akasofu,~S.-I. and Meng,~C.-I.: A study of polar magnetic substorms, J Geophys. Res., 74, 292–313, 1969.; Amm,~O., Aksnes,~A., Stadsnes,~J., Ostgaard,~N., Vondrak,~R. R., Germany,~G. A., Lu,~G., and Viljanen,~A.: Mesoscale ionospheric electrodynamics of omega bands determined from ground-based electromagnetic and satellite optical observations, Ann. Geophys., 23, 325–342 2005.; Atkinson,~G.: The current system of geomagnetic bays, J Geophys. Res., 72, 6063–6067, 1967.; Anderson,~P. C., Hanson,~W. B., Heelis,~R. A., Craven,~J. D., Baker,~D. N., and Frank,~L. A.: A proposed production model of rapid subauroral ion drifts and their relationship to substorm evolution, J. Geophys. Res., 98, 6069–6078, 1993.; Angelopoulos,~V., Baumjohann,~W., Kennel,~C. F., Coroniti,~F. V., Kivelson,~M. G., Pellat,~R., Walker,~R. J., Lühr,~H., and Paschmann,~G.: Bursty bulk flows in the central plasma sheet, J. Geophys Res., 97, 4027–4039, 1992.; Baker,~D. N., Akasofu,~S.-I., Baumjohann,~W., Bieber,~J. W., Fairfield,~D. H., Hones~Jr.,~E. W., Mauk,~B., McPherron,~R. L., and Moore,~T. E.: Substorms in the magnetosphere, in Solar Terrestrial Physics: Present and Future, NASA reference publication 1120, pp. 8.1–8.55, 1984.; Baker,~K. B. and Wing,~S.: A new magnetic coordinate system for conjugate studies at high latitudes, J. Geophys. Res., 94, 9139–9143, 1989.; Baumjohann,~W., Paschmann,~G., and Lühr,~H.: Characteristics of high-speed flows in the plasma sheet, J. Geophys. Res., 95, 3801–3809, 1990.; Blanchard,~G. T., Lyons,~L. R.,~and de~la~Beaujardière,~O.: Magnetotail reconnection rate during magnetospheric substorms, J. Geophys. Res., 102, 24 303–24 312, 1997.; Blanchard,~G. T., Lyons,~L. R., de~la~Beaujardière,~O. Doe,~R. A., and Mendillo,~M.: Measurements of the magnetotail reconnection rate, J. Geophys. Res., 101, 15265–15276, 1996.; Bostrom,~R.: A model of the auroral electrojets, J Geophys. Res., 69, 4963–4999, 1964.; Bristow~W. A., Otto,~A., and Lummerzheim,~D.: Substorm convection patterns observed by the Super Dual Auroral Radar Network, J. Geophys. Res., 106, 24 593–24 609, 2001.; Cowley,~S. W. H. and Lockwood,~M.: Excitation and decay of solar wind-driven flows in the magnetosphere-ionosphere system, Ann. Geophys., 10, 103–115, 1992.; Cowley,~S. W. H.: Excitation of flow in the Earth's magnetosphere-ionosphere system: observations by incoherent-scatter radar, in: Polar Cap Boundary Phenomena, edited by:~Egeland, A.,~Moen, J., and~Lockwood, M., Kluwer Academic Publ., Dordrecht, p 127, 1998.; Cowley,~S. W. H., Khan,~H., and Stockton-Chalk,~A.: Plasma flow in the coupled magnetosphere-ionosphere system and its relationship to the substorm cycle, in: Substorms-4, edited by:~Kokobun, S. and~Kamide, Y., Terra Sci. Publ. Co., Tokyo, p 623–628, 1998.; Clauer,~C. R. and Kamide,~Y.: DP-1 and DP-2 current systems for the March 22, 1979 substorms, J Geophys. Res., 90, 1343–1354, 1985.; de~la~Beaujardière,~O., Lyons,~L.R., and Friis-Christensen,~E.: Sondrestrom radar measurements of the reconnection electric field, J. Geophys. Res., 96, 13 907–13 912, 1991.; Dyson,~P. L. and Develin,~J. C.: The Tasman International Geospace Envirenoment Radar, The Physicist (The Australian Institute of Physics), 37, 48–53, 2000.; de~la~Beaujardière,~O., Lyons,~L. R., Ruohoniemi,~J. M., Friis-Christensen,~E.

 

Click To View

Additional Books


  • Applications of Kalman Filters Based on ... (by )
  • On a Magnetosphere Disturbed by Solar Wi... (by )
  • Global Variation in the Long-term Season... (by )
  • Europa's Alfvén Wing: Shrinkage and Disp... (by )
  • Airborne Lidar Study of the Vertical Dis... (by )
  • Noctilucent Clouds Observed from the Uk ... (by )
  • Observations of the Response Time of Hig... (by )
  • The Dynamical Background of Polar Mesosp... (by )
  • Themis Observation of a Substorm Event o... (by )
  • Sensitivity of the Freie Universität Ber... (by )
  • A One-way Nested Eddy Resolving Model of... (by )
Scroll Left
Scroll Right

 



Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Fair are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.