Optics of Jumping Sundogs

Abstract

Jumping sundogs, or crown flashes, are a rare and interesting atmospheric phenomenon characterized by beams of light dancing across the sky. Despite their rarity, social media videos have captured numerous instances of this phenomenon under seemingly similar conditions. By analyzing these videos, we have investigated the structure and dynamics of jumping sundogs. Our analysis reveals that these events require specific ice crystal types and atmospheric conditions. The distinctive feather-like luminescence of jumping sundogs is attributed to the orientation of ice crystals influenced by electric fields within the cloud. These crystals interact with sunlight, creating the observed luminous pattern. We propose that electrical charges near the base of the crown flash generate an electric field that guides the ice crystal orientation. Jumping sundogs might exhibit a “memory effect”, because in a certain temperature range, their orientation could depend on their past state (aligned), unlike the random orientation at higher temperatures. Jumping sundogs are a type of critical phenomena, where ice crystals align in a specific direction below a critical temperature and orient randomly above it.

Received: 21 October 2024 | Revised: 11 December 2024 | Accepted: 24 January 2025

Conflicts of Interest

The authors declare that they have no conflicts of interest to this work.

Data Availability Statement

List of jumping sundogs videos at https://www.researchgate.net/publication/381039244_Jumping_Sundogs_List_of_Videos. Data are available from the corresponding author upon reasonable request.

Author Contribution Statement

Alberto Tufaile: Conceptualization, Methodology, Software, Validation, Formal analysis, Investigation, Resources, Data curation, Writing – original draft, Writing – review & editing, Visualization, Supervision, Project administration. Adriana Pedrosa Biscaia Tufaile: Conceptualization, Methodology, Validation, Formal analysis, Resources, Data curation, Writing review & editing, Visualization, Project administration.