We report synchronized optical observations of sprites in Israel during the winters of 2006/7-2007/8. Based on several events, we suggest that the elements of columniform sprites are organized in spaced intervals on the circumference of a circle centered directly above, or a little offset, to the vertical direction from the parent lightning. In 2D images most of the cases show columns to be arranged in highly eccentric elliptical forms or in straight rows. The analysis of the optical images provided the geometrical dimensions of the columns and their spatial organization. We used an electrostatic model of the QE field with reasonable assumptions on the location and magnitude of the cloud charge center, constrained by ELF evaluation of the Charge Moment Change in the parent flash, to show that the observed diameter of the columnar arrangement closely matches the conventional breakdown field line contour at the same altitude.
|Original language||American English|
|Number of pages||5|
|Journal||Journal of Atmospheric and Solar-Terrestrial Physics|
|State||Published - Dec 2009|
Bibliographical noteFunding Information:
The ILAN campaigns are dedicated to the memory of the first Israeli astronaut Col. Ilan Ramon, who died with the crew of the Space Shuttle Columbia in February 2003. This research was supported by the Israel Science Foundation grants 145/03 and 1315/04 and matching funds from the Institute of Earth Sciences at Hebrew University. We wish to thank J. Bór and G. Sátori of the Geodetic and Geophysical Research Institute of the HAS, Sopron, Hungary, for supplying the CMC data for the analyzed events. The Ring Foundation for Environmental Studies provided fellowship for the first author. Additional support was received from the Research Authority of The Open University. Thanks to Mr. Yossi Sherer for helping with camera mounting in Jerusalem and to Mrs. Y. Yair who first noticed the unique column arrangement.
- Columniform sprites
- Optical observations
- Winter thunderstorms