Signatures of Polar Vortex Weakening in the MLTI: A Review

Abstract This paper is a collaborative effort that originated at the International Space Science Institute Workshop on “Physical links between Weather and Climate in Space and the Lower Atmosphere” held 22–26 January 2024. Many scientists attended that workshop and contributed their expertise related to polar vortex impacts on upper atmosphere variability. This paper summarizes well-known and newly reported signatures of polar vortex weakening on mesosphere–lower-thermosphere (MLT) temperature, winds, composition, planetary waves, gravity waves, tides, and ionospheric foF2. A variety of observational and modeling results are shown and are consistent with previously published variations in the dynamical and chemical state of the MLT and ionosphere during weak vortex events. We present Superposed Epoch Analysis (SEA) of upper atmosphere diagnostics and phenomena where day 0 is the onset of major SSWs. We also present SEAs where day 0 is the onset of stratopause warmings followed by elevated stratopause events. Our goal in performing two SEAs is to test the sensitivity of 10 hPa versus 1 hPa winds to predict upper atmosphere variability. Results suggest that zonal winds and the semidiurnal migrating solar tide (SW2) in the MLT are more sensitive to zonal wind reversals at 1 hPa rather than 10 hPa. Alternatively, the non-migrating DW2 tide in the equatorial upper mesosphere is best predicted by planetary wave-1 amplitudes in the winter high-latitude upper stratosphere rather than zonal wind reversals. A notable aspect of both SEAs is extremely large event-to-event variability in all diagnostics. Thus, conclusions drawn based on any one event are less robust than those based on many events.

Authors

Institutions

Publication Details

Journal
Surveys in Geophysics
Published
2025-08-14
DOI
https://doi.org/10.1007/s10712-025-09899-3
Citations
2
Primary Topic
Ionosphere and magnetosphere dynamics
Type
article
Field-Weighted Citation Impact
2.31

Funders

Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

Signatures of Polar Vortex Weakening in the MLTI: A Review

Yosuke Yamazaki, Gunter Stober, Claudia Stephan, A. Marchaudon et al.
2 citations
Surveys in Geophysics
Ionosphere and magnetosphere dynamics
2.31
article

Signatures of Polar Vortex Weakening in the MLTI: A Review

Yosuke Yamazaki, Gunter Stober, Claudia Stephan, A. Marchaudon, Michael Bittner, N. M. Pedatella, Ville Maliniemi, Willem van Caspel, E. Becker, Deepali Aggarwal, Bernd Funke, V. Lynn Harvey, R. S. Lieberman, Yunpeng Jia, Л. П. Гончаренко, Hilde Nesse Tyssøy, Carsten Schmidt, Ge Shi, Sabine Wüst, Hanli Liu, Noora Partamies
article en
2 citations

Abstract

Abstract This paper is a collaborative effort that originated at the International Space Science Institute Workshop on “Physical links between Weather and Climate in Space and the Lower Atmosphere” held 22–26 January 2024. Many scientists attended that workshop and contributed their expertise related to polar vortex impacts on upper atmosphere variability. This paper summarizes well-known and newly reported signatures of polar vortex weakening on mesosphere–lower-thermosphere (MLT) temperature, winds, composition, planetary waves, gravity waves, tides, and ionospheric foF2. A variety of observational and modeling results are shown and are consistent with previously published variations in the dynamical and chemical state of the MLT and ionosphere during weak vortex events. We present Superposed Epoch Analysis (SEA) of upper atmosphere diagnostics and phenomena where day 0 is the onset of major SSWs. We also present SEAs where day 0 is the onset of stratopause warmings followed by elevated stratopause events. Our goal in performing two SEAs is to test the sensitivity of 10 hPa versus 1 hPa winds to predict upper atmosphere variability. Results suggest that zonal winds and the semidiurnal migrating solar tide (SW2) in the MLT are more sensitive to zonal wind reversals at 1 hPa rather than 10 hPa. Alternatively, the non-migrating DW2 tide in the equatorial upper mesosphere is best predicted by planetary wave-1 amplitudes in the winter high-latitude upper stratosphere rather than zonal wind reversals. A notable aspect of both SEAs is extremely large event-to-event variability in all diagnostics. Thus, conclusions drawn based on any one event are less robust than those based on many events.

Surveys in Geophysics
NSF National Center for Atmospheric Research (US), NSF NCAR High Altitude Observatory (US), University of Bern (CH), Centre National de la Recherche Scientifique (FR), Oeschger Centre for Climate Change Research (CH), Goddard Space Flight Center (US), Norwegian Meteorological Institute (NO), Université Fédérale de Toulouse Midi-Pyrénées (FR), University of Augsburg (DE), University of Colorado Boulder (US), Norwegian University of Science and Technology (NO), Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) (DE), Laboratory for Atmospheric and Space Physics (US), Leibniz Institute of Atmospheric Physics at the Rostock University (DE), Northwest Research Associates (US), Instituto de Astrofísica de Andalucía (ES), Institut de Recherche en Astrophysique et Planétologie (FR), University of Bergen (NO), University of Rostock (DE), University Centre in Svalbard (SJ), Clemson University (US), University of Oulu (FI)
National Science Foundation, National Aeronautics and Space Administration, European Commission, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Bundesministerium für Bildung und Forschung, Nuclear Safety and Security Commission, Ames Research Center, Goddard Space Flight Center, Langley Research Center, Agencia Estatal de Investigación
Openalex Percentile: Top 10%
Ionosphere and magnetosphere dynamics
2.31
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.