Winter Noctilucent Clouds Following Sudden Stratospheric Warming: First Observations

TL;DR

This paper reports the first observations of winter noctilucent clouds in Siberia, linked to stratospheric warming and polar vortex displacement, with detailed measurements and satellite data analysis.

Contribution

It presents the first documented occurrence of winter noctilucent clouds and analyzes their connection to stratospheric temperature and polar vortex dynamics.

Findings

Noctilucent clouds observed in winter at 70.1 km altitude.

Cloud formation coincided with deep mesosphere temperature minimum.

Satellite data indicated stratospheric warming and water vapor changes.

Abstract

Mesospheric structures identical to summer noctilucent clouds were observed during the nights of December 17-19, 2024 in Siberian Russia. Basing on the available photo data, the mean altitude of the clouds 70.1+-1.5 km was measured by umbral colorimetric method. This coincided spatially and temporary with deep temperature minimum below 160K in mesosphere, followed the polar vortex displacement and warming of stratosphere below the clouds. The satellite data on temperature and water vapor is used to study the nature of this unexpected event.