Comments on ‘‘Production of polar cap electron density patches by transient magnetopause reconnections’’

Abstract. Observations by the EISCAT Svalbard radar in summer have revealed electron density enhancements in the magnetic noon sector under conditions of IMF Bz southward. The features were identified as possible candidates for polar-cap patches drifting anti-Sunward with the plasma flow. Supporting measurements by the EISCAT mainland radar, the CUTLASS radar and DMSP satellites, in a multi-instrument study, suggested that the origin of the structures lay upstream at lower latitudes, with the modulation in density being attributed to variability in soft-particle precipitation in the cusp region. It is proposed that the variations in precipitation may be linked to changes in the location of the reconnection site at the magnetopause, which in turn results in changes in the energy distribution of the precipitating particles.Key words: Ionosphere (ionosphere-magnetosphere interactions; plasma temperature and density; polar ionosphere)

Download Full-text

Polar cap electron density distribution from IMAGE radio plasma imager measurements: Empirical model with the effects of solar illumination and geomagnetic activity

Journal of Geophysical Research Atmospheres ◽

10.1029/2007ja012566 ◽

2008 ◽

Vol 113 (A1) ◽

pp. n/a-n/a ◽

Cited By ~ 14

Author(s):

Patrick A. Nsumei ◽

Bodo W. Reinisch ◽

Paul Song ◽

Jiannan Tu ◽

Xueqin Huang

Keyword(s):

Density Distribution ◽

Electron Density ◽

Geomagnetic Activity ◽

Empirical Model ◽

Electron Density Distribution ◽

Polar Cap

Download Full-text

Warm O+polar wind and the De-1 polar cap electron density profile

Geophysical Research Letters ◽

10.1029/93gl01980 ◽

1993 ◽

Vol 20 (16) ◽

pp. 1715-1717 ◽

Cited By ~ 9

Author(s):

C. Wing Ho ◽

J. L. Horwitz

Keyword(s):

Electron Density ◽

Density Profile ◽

Electron Density Profile ◽

Polar Cap ◽

Polar Wind

Download Full-text

Break up of a polar cap patch in the nightside ionosphere due to a flow channel event

10.5194/egusphere-egu2020-17726 ◽

2020 ◽

Author(s):

Elizabeth Donegan-Lawley ◽

Alan Wood ◽

Gareth Dorrian ◽

Alexandra Fogg ◽

Timothy Yeoman ◽

...

Keyword(s):

Electron Density ◽

Global Navigation Satellite System ◽

Satellite System ◽

Flow Channel ◽

Navigation Satellite ◽

Polar Cap ◽

Incoherent Scatter ◽

Radar Network ◽

Incoherent Scatter Radars ◽

Global Navigation Satellite

Flow channel events have previously been observed breaking up polar cap patches on the dayside ionosphere but, to the best of our knowledge, have not been observed on the nightside. We report observations of a flow channel event in the evening of the 9th January 2019 under quiet geomagnetic conditions. This multi-instrument study was undertaken using a combination of multiple EISCAT (European Incoherent Scatter) radars, SuperDARN (Super Dual Auroral Radar Network), MSP (Meridian Scanning Photometer) and GNSS (Global Navigation Satellite System) scintillation data. These data were used to build a picture of the evening&#8217;s observations from 1800 to 2359 UT. The flow channel event lasted a total of 13 minutes and was responsible for segmenting a polar cap patch. A decrease in electron density was observed, from a patch value of 1.4x1011 m3 to a minimum value of 5x1010 m3. In addition, ion velocities in excess of 1000 ms-1 and ion temperatures of greater than 2000 K were also observed.&#160;

Download Full-text