All Physics Faculty Publications
Document Type
Article
Journal/Book Title/Conference
Geophysical Research Letters
Volume
43
Issue
6
Publisher
Wiley-Blackwell Publishing, Inc.
Publication Date
3-17-2016
Award Number
NSF, Division of Atmospheric and Geospace Sciences 1441774
Funder
NSF, Division of Atmospheric and Geospace Sciences
First Page
2422
Last Page
2428
Abstract
The source and structuring mechanisms for F region density patches have been subjects of speculation and debate for many years. We have made a survey of mappings of total electron content (TEC) between the years 2009 and 2015 from the web‐based Madrigal data server in order to determine when patches and/or a tongue of ionization (TOI) have been present in the Northern Hemisphere polar cap; we find that there is a UT and seasonal dependence that follows a specific pattern. This finding sheds considerable light upon the old question of the source of polar cap patches, since it virtually eliminates potential patch plasma sources that do not have a UT/seasonal dependence, for example, particle precipitation or flux transfer events. We also find that the frequency of occurrence of patches or TOIs has little to do with the level of geomagnetic activity.
Recommended Citation
David, M., Sojka, J. J., Schunk, R. W., and Coster, A. J. (2016), Polar cap patches and the tongue of ionization: A survey of GPS TEC maps from 2009 to 2015, Geophys. Res. Lett., 43, 2422– 2428, https://doi.org/10.1002/2016GL068136.
https://doi.org/10.1002/2016GL068136
