Geomagnetic control of polar mesosphere summer echoes
Item
Title (Dublin Core)
Geomagnetic control of polar mesosphere summer echoes
Description (Dublin Core)
Using observations with the ALOMAR SOUSY
radar near Andenes (69.3°N, 16.0°E) from 1994 until 1997 polar mesosphere
summer echoes (PMSE) have been investigated in dependence on geomagnetic K
indices derived at the Auroral Observatory Tromsø (69.66°N, 18.94°E). During
night-time and morning hours a significant correlation between the
signal-to-noise ratio (SNR) of the radar results and the geomagnetic K indices
could be detected with a maximum correlation near midnight. The correlation
becomes markedly smaller in the afternoon and early evening hours with a minimum
near 17 UT. This diurnal variation is in reasonable agreement with riometer
absorption at Ivalo (68.55°N, 27.28°E) and can be explained by the diurnal
variation of ionization due to precipitating high energetic particles.
Therefore, a part of the diurnal PMSE variation is caused by this particle
precipitation. The variability of the solar EUV variation, however, has no
significant influence on the PMSE during the observation period.<br><br><b>Keywords: </b>Ionosphere (auroral ionosphere) -
Magnetospheric physics (energetic particles, precipitating) - Radio science
(remote sensing)
radar near Andenes (69.3°N, 16.0°E) from 1994 until 1997 polar mesosphere
summer echoes (PMSE) have been investigated in dependence on geomagnetic K
indices derived at the Auroral Observatory Tromsø (69.66°N, 18.94°E). During
night-time and morning hours a significant correlation between the
signal-to-noise ratio (SNR) of the radar results and the geomagnetic K indices
could be detected with a maximum correlation near midnight. The correlation
becomes markedly smaller in the afternoon and early evening hours with a minimum
near 17 UT. This diurnal variation is in reasonable agreement with riometer
absorption at Ivalo (68.55°N, 27.28°E) and can be explained by the diurnal
variation of ionization due to precipitating high energetic particles.
Therefore, a part of the diurnal PMSE variation is caused by this particle
precipitation. The variability of the solar EUV variation, however, has no
significant influence on the PMSE during the observation period.<br><br><b>Keywords: </b>Ionosphere (auroral ionosphere) -
Magnetospheric physics (energetic particles, precipitating) - Radio science
(remote sensing)
Creator (Dublin Core)
J. Bremer
P. Hoffmann
T. L. Hansen
Subject (Dublin Core)
Science
Q
Physics
QC1-999
Geophysics. Cosmic physics
QC801-809
Publisher (Dublin Core)
Copernicus Publications
Date (Dublin Core)
2000-02-01T00:00:00Z
Type (Dublin Core)
article
Identifier (Dublin Core)
10.1007/s00585-000-0202-z
0992-7689
1432-0576
https://doaj.org/article/515384a156d940a38815f9e263ac8023
Source (Dublin Core)
Annales Geophysicae, Vol 18, Pp 202-208 (2000)
Language (Dublin Core)
EN
Relation (Dublin Core)
https://www.ann-geophys.net/18/202/2000/angeo-18-202-2000.pdf
https://doaj.org/toc/0992-7689
https://doaj.org/toc/1432-0576
Provenance (Dublin Core)
Journal Licence: CC BY