Journal article
Spatial localization and ducting of EMIC waves: Van Allen Probes and ground‐based observations
Geophysical research letters, Vol.41(3), pp.785-792
02/16/2014
DOI: 10.1002/2013GL058581
Abstract
On 11 October 2012, during the recovery phase of a moderate geomagnetic storm, an extended interval (> 18 h) of continuous electromagnetic ion cyclotron (EMIC) waves was observed by Canadian Array for Real‐time Investigations of Magnetic Activity and Solar‐Terrestrial Environment Program induction coil magnetometers in North America. At around 14:15 UT, both Van Allen Probes B and A (65° magnetic longitude apart) in conjunction with the ground array observed very narrow (ΔL ~ 0.1–0.4) left‐hand polarized EMIC emission confined to regions of mass density gradients at the outer edge of the plasmasphere at L ~ 4. EMIC waves were seen with complex polarization patterns on the ground, in good agreement with model results from Woodroffe and Lysak (2012) and consistent with Earth's rotation sweeping magnetometer stations across multiple polarization reversals in the fields in the Earth‐ionosphere duct. The narrow L‐widths explain the relative rarity of space‐based EMIC occurrence, ground‐based measurements providing better estimates of global EMIC wave occurrence for input into radiation belt dynamical models.
Key Points
Continuous EMIC waves confined to narrow L‐shells near plasma density gradients
The narrow L‐widths explains low in‐situ EMIC occurrence
Ground measurements provide better estimates of global EMIC wave occurrence
Details
- Title: Subtitle
- Spatial localization and ducting of EMIC waves: Van Allen Probes and ground‐based observations
- Creators
- I. R Mann - University of AlbertaM. E Usanova - University of AlbertaK Murphy - University of AlbertaM. T Robertson - University of AlbertaD. K Milling - University of AlbertaA Kale - University of AlbertaC Kletzing - University of IowaJ Wygant - University of MinnesotaS Thaller - University of MinnesotaT Raita - Sodankylä Geophysical Observatory Sodankylä Finland
- Resource Type
- Journal article
- Publication Details
- Geophysical research letters, Vol.41(3), pp.785-792
- DOI
- 10.1002/2013GL058581
- ISSN
- 0094-8276
- eISSN
- 1944-8007
- Number of pages
- 8
- Language
- English
- Date published
- 02/16/2014
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9984199832802771
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