Articles | Volume 35, issue 3
https://doi.org/10.5194/angeo-35-475-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/angeo-35-475-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
ANGEO Communicates
| 
22 Mar 2017
ANGEO Communicates |
| 22 Mar 2017
Relation of anomalous F region radar echoes in the high-latitude ionosphere to auroral precipitation
School of Electrical Engineering, Royal Institute of Technology KTH, Stockholm, Sweden
School of Physics and Astronomy, University of Southampton, Southampton, UK
Nicola M. Schlatter
School of Electrical Engineering, Royal Institute of Technology KTH, Stockholm, Sweden
Nickolay Ivchenko
School of Electrical Engineering, Royal Institute of Technology KTH, Stockholm, Sweden
Lorenz Roth
School of Electrical Engineering, Royal Institute of Technology KTH, Stockholm, Sweden
Alexander Karlsson
School of Electrical Engineering, Royal Institute of Technology KTH, Stockholm, Sweden
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Pulsating aurora are ubiquitous events that constitute a large amount of energy transfer to the ionosphere. Still there are unsolved issues regarding their formation. Using high-resolution optical and radar data, we find that it is the flux of high-energy electrons that get reduced during the OFF period of the pulsations. We also report on dips in brightness at the transition between ON and OFF, and asymmetric rise and fall times, which may have implications for understanding the pulsations.
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Anomalous strong echoes with three frequency peaks are occasionally seen with incoherent scatter radars in the ionosphere near 200 km altitude at high latitudes. We investigate how they relate to electron precipitation, by finding the resulting peak electron density and the height of the peak, respectively. We find that occurrence rate increases with density and decreases with height, indicating a correlation between the echoes and precipitating electrons with high energy and energy flux.
Anomalous strong echoes with three frequency peaks are occasionally seen with incoherent scatter...
