Sprites as luminous columns of ionization produced by quasi‐electrostatic thundercloud fields

Abstract

Quasi‐electrostatic (QE) fields which exist above thunderclouds after lightning discharges can lead to the formation of columnar channels of breakdown ionization and carrot‐like vertical luminous structures with typical transverse dimension ∼5–10 km spaning an altitude range from ∼80 km to well below ∼50 km. The carrot‐like forms closely resemble those observed in sprites. Results indicate that the appearance of optical emissions can be significantly delayed in time (∼1–20 ms) with respect to the causative lightning discharge.