Three-Dimensional Velocity Analysis and Particle Size Dynamics from Multi-Site RGB-Photometry of Noctilucent Clouds

TL;DR

This paper introduces a novel multi-site RGB-photometry method to analyze noctilucent cloud velocities and particle size dynamics, revealing the influence of meridional motion and temperature gradients.

Contribution

The paper develops an updated technique for measuring cloud velocity and particle size evolution using wide-angle three-color cameras, applied to recent observational data.

Findings

Meridional motion significantly affects particle size changes.

Particle size evolution is influenced by latitudinal temperature gradients.

The method successfully determines three velocity components and particle size derivatives.

Abstract

A method for measuring the altitude and particle size of noctilucent clouds, based on positioning and photometry from wide-angle three-color cameras, has been developed to determine the three velocity components, particle radius, and its derivative with respect to time for different cloud fragments. The updated method is applied to observational data of bright clouds during the summers of 2023-2025. Meridional motion of the cloud is found to be the principal factor driving the change in particle size. The effect of particle size evolution in the presence of a strong latitudinal temperature gradient is also studied.