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arXiv · 2511.20089

Noctilucent Clouds Modulated by Strong 5-day Planetary Wave in 2025: Amplitudes, Phases and Altitudes Based on Ground-Based Observations and Satellite Temperature Data

Oleg S. Ugolnikov·Ilya S. Yankovsky·Nikolay N. Pertsev·Vladimir I. Perminov·Maxim V. Klimenko·Ekaterina N. Tipikina·Alexey V. Popov·Andrey M. Tatarnikov·Sergey G. Zheltoukhov·Sergey A. Potanin·Egor O. Ugolnikov·Olga Yu. Golubeva·Andrey L. Kotikov·Alexey S. Sushkov·Egor A. Volkov
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Abstract

During the summer season of 2025, noctilucent clouds (NLC) were observed at the latitudes 55-60N from the late May until the late August. A distinct 5-day periodicity in their occurrence emerged following the summer solstice. Analysis of EOS Aura/MLS satellite data revealed that this effect was driven by a westward 5-day planetary wave, the amplitude of which was twice that of any previous northern summer since the start of the EOS Aura measurements in 2005. This study details the evolution of this exceptional planetary wave throughout the summer. Furthermore, NLC altitudes were determined via triangulation and colorimetry and were compared with MLS temperature profiles, enabling the determination of a mean positive phase lag for NLC occurrence relative to the temperature minimum.

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Oleg S. Ugolnikov, Ilya S. Yankovsky, Nikolay N. Pertsev, Vladimir I. Perminov, Maxim V. Klimenko, Ekaterina N. Tipikina, Alexey V. Popov, Andrey M. Tatarnikov, Sergey G. Zheltoukhov, Sergey A. Potanin, Egor O. Ugolnikov, Olga Yu. Golubeva, Andrey L. Kotikov, Alexey S. Sushkov, Egor A. Volkov. 2025-11-25. Noctilucent Clouds Modulated by Strong 5-day Planetary Wave in 2025: Amplitudes, Phases and Altitudes Based on Ground-Based Observations and Satellite Temperature Data. https://arxiv.org/abs/2511.20089

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