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Occurrence and average behavior of pulsating aurora
Motivated by recent event studies and modelling efforts on pulsating aurora, which conclude that the precipitation energy during these events is high enough to cause significant chemical changes inExpand
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Statistical properties of substorms during different storm and solar cycle phases
Abstract. Substorm properties during different storm phases have been studied using an automated recognition of substorm and storm phases in the auroral electrojet (AL) and ring current (Dst) indexExpand
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From space weather toward space climate time scales: Substorm analysis from 1993 to 2008
[1] Magnetic activity in the Northern Hemisphere auroral region was examined during solar cycles 22 and 23 (1993–2008). Substorms were identified from ground-based magnetic field measurements by anExpand
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Statistical study of auroral spirals
We present results of a statistical study of 189 auroral spiral forms. The data set was collected by a systematic examination of the images recorded at five all-sky camera (ASC) stations in northernExpand
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Numeric Image Features for Detection of Aurora
The electromagnetic coupling of the solar wind, Earth's magnetic field, and the upper atmosphere allows us to study the near-Earth space phenomena by monitoring the auroral displays in the polarExpand
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Differences in geomagnetic storms driven by magnetic clouds and ICME sheath regions
[1] Twenty-eight geomagnetic storms driven by magnetic clouds or by sheath regions ahead of interplanetary coronal mass ejections are examined to address the dependence of the driver properties onExpand
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Supermagnetosonic subsolar magnetosheath jets and their effects: from the solar wind to the ionospheric convection
Abstract. It has recently been proposed that ripples inherent to the bow shock during radial interplanetary magnetic field (IMF) may produce local high speed flows in the magnetosheath. These jetsExpand
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Earthward plasma sheet flows during substorm phases
[1] Magnetic reconnection in the Earth's magnetotail converts open magnetic flux to closed, producing fast flows in the plasma sheet. Earthward fast flows can thus be used as a proxy for energy andExpand
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Using colour in auroral imaging
The prototype of an auroral colour camera named Rainbow was run at the Auroral Station in Adventdalen, Svalbard, Norway, during a Finnish optical campaign in February, 2004. Instead of narrowExpand
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Observations of the auroral width spectrum at kilometre-scale size
This study examines auroral colour camera data from the Canadian Dense Array Imaging SYstem (DAISY). The Dense Array consists of three imagers with different narrow (compared to all-sky view)Expand
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