Reversed flow events in the winter cusp ionosphere observed by the European Incoherent Scatter (EISCAT) Svalbard radar

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Magnetospheric Physics: Plasma Convection (2463), Magnetospheric Physics: Cusp, Ionosphere: Polar Cap Ionosphere, Magnetospheric Physics: Polar Cap Phenomena, Magnetospheric Physics: Magnetosphere/Ionosphere Interactions (2431)

Scientific paper

High-resolution fast azimuth sweeps by the European Incoherent Scatter (EISCAT) Svalbard radar provide an unparalleled opportunity to study small-scale flow disturbances in the cusp ionosphere. Observations from 11 days of the winter cusp ionosphere of high-resolution ion flow data have been analyzed. Transient channels of reversed plasma flow appear to be a regular feature of the cusp, and they were seen in 16% of 767 analyzed EISCAT Svalbard Radar (ESR) scans. We introduce a new descriptive term, reversed flow events (RFEs), for this class of events. RFEs are defined as longitudinally elongated segments of transiently enhanced ion flow in the direction opposite to the background flow. RFEs typically occurred near the cusp inflow region in association with enhancements in the polar cap convection observed by the Super Dual Auroral Radar Network (SuperDARN). Their lifetime was found to be ~19 min on average. Their longitudinal dimension typically exceeded the ESR field of view (>400-600 km), and ranged from ~50 to 250 km in latitude. The occurrence rate of RFEs appears independent of the B Z and B Y component polarity of the interplanetary magnetic field (IMF), and RFEs occurred for clock angles between 40° and 240°. RFE ion flow was in 95% of the cases documented to oppose the magnetic tension force, and RFEs cannot be interpreted in terms of newly opened flux. RFEs formed one by one and never simultaneously in pairs. To explain these observations, we propose an asymmetric version of the Southwood (1987) twin cell flux transfer event model to account for significant IMF B Y , in which only the poleward cell located on open field lines develops.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Reversed flow events in the winter cusp ionosphere observed by the European Incoherent Scatter (EISCAT) Svalbard radar does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Reversed flow events in the winter cusp ionosphere observed by the European Incoherent Scatter (EISCAT) Svalbard radar, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reversed flow events in the winter cusp ionosphere observed by the European Incoherent Scatter (EISCAT) Svalbard radar will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1866947

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.