On the Emergence Mechanism of Carrot Sprites
Abstract
We investigate the launch of negative upward streamers from sprite glows. This phenomenon is readily observed in high‐speed observations of sprites and underlies the classification of sprites into carrot or column types. First, we describe how an attachment instability leads to a sharply defined region in the upper part of the streamer channel. This region has an enhanced electric field, low conductivity and strongly emits in the first positive system of molecular nitrogen. We identify it as the sprite glow. We then show how, in the most common configuration of a carrot sprite, several upward streamers emerge close to the lower boundary of the glow, where negative charge gets trapped and the lateral electric field is high enough. These streamers cut off the current flowing toward the glow and lead to the optical deactivation of the glow above. Finally, we discuss how our results naturally explain angel sprites.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 16, 2020
- Source ID
- 10.1029/2019gl085776
Entities
People
- A. Luque
- A. Malagón‐romero
- H. C. Stenbaek‐nielsen
- J. Teunissen
- M. G. Mcharg
- U. Ebert
Organizations
- Eindhoven University of Technology
- National Science Foundation
- Research Foundation - Flanders
- Seventh Framework Programme
- United States Air Force Academy
- University of Alaska System