Estimates of the field-aligned current density in current-carrying filaments using auroral zone ground-based observations [PDF]
Annales Geophysicae, 2001 We described the ground signatures of dynamic substorm features as observed by the imaging riometer, magnetometers and all-sky camera (ASC) at Kilpisjärvi, Finland on 5 and 25 October 1999 during the late evening hours.
M. A. Danielides, S. Shalimov, J. Kangas
doaj +3 more sources
Cosmic radio noise absorption events associated with equatorward drifting arcs during a substorm growth phase [PDF]
Annales Geophysicae, 2004 Cosmic radio noise absorption (CNA) events associated with equatorward drifting arcs during a substorm growth phase are studied by using simultaneous optical auroral, IRIS imaging riometer and EISCAT incoherent scatter radar measurements.
J. R. T. Jussila +3 more
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Ionospheric response to an auroral substorm [PDF]
Geophysical Research Letters, 1997 The response of the ionosphere to a representative auroral substorm was simulated. The response was found to be significant at all altitudes in a large spatial region near midnight magnetic local time. In this midnight region, there were Te and Ti hot spots, substantial O+ → NO+ composition changes, non‐Maxwellian velocity distributions, transient ion ...
Schunk, Robert W. +3 more
openaire +2 more sources
Spatial distribution of conductances and currents associated with a north-south auroral form during a multiple-substorm period [PDF]
Annales Geophysicae, 1999 Using the method of characteristics to invert ground-based data of the ground magnetic field disturbance and of the ionospheric electric field, we obtain spatial distributions of ionospheric conductances, currents, and field-aligned currents (FACs ...
O. Amm, A. Pajunpää, U. Brandström
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A new scenario applying traffic flow analogy to poleward expansion of auroras [PDF]
Annales Geophysicae, 2019 Transient westward electric fields from the magnetosphere generate equatorward plasma drifts of the order of kilometers per second in the auroral ionosphere.
O. Saka
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Geophysical Monograph Series, Page i-xiv., 2021 Exploring the links between Large Igneous Provinces and dramatic environmental impact
An emerging consensus suggests that Large Igneous Provinces (LIPs) and Silicic LIPs (SLIPs) are a significant driver of dramatic global environmental and biological changes, including mass extinctions.
wiley +1 more source
Phenomena in the ionosphere-magnetosphere system induced by injection of powerful HF radio waves into nightside auroral ionosphere [PDF]
, 2005 International audienceExperimental results from three ionospheric HF pumping experiments in overdense E or F regions are summarized. The experiments were conducted by the use of the EISCAT HF Heating facility located near Tromsø, Norway, allowing HF ...
N. F. Blagoveshchenskaya +13 more
core +1 more source
Travelling ionospheric disturbance properties deduced from Super Dual Auroral Radar measurements [PDF]
Annales Geophysicae, 2000 Based on modeling of the perturbations in power and elevation angle produced by travelling ionospheric disturbances (TIDs), and observed by the Super Dual Auroral Radar Network, procedures for determining the TID properties are suggested.
J. W. MacDougall +5 more
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Letter to the Editor: First complementary observations by ionospheric tomography, the EISCAT Svalbard radar and the CUTLASS HF radar [PDF]
Annales Geophysicae, 1998 Experimental results are presented from ionospheric tomography, the EISCAT Svalbard radar and the CUTLASS HF radar. Tomographic measurements on 10 October 1996, showing a narrow, field-aligned enhancement in electron density in the post-noon sector of
C. N. Mitchell +5 more
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IMF dependence of the open-closed field line boundary in Saturn's ionosphere, and its relation to the UV auroral oval observed by the Hubble Space Telescope [PDF]
, 2007 We study the dependence of Saturn's magnetospheric magnetic field structure on the interplanetary magnetic field (IMF), together with the corresponding variations of the open-closed field line boundary in the ionosphere.
Badman, S. V. +13 more
core +1 more source