TY  - JOUR
A1  - Yamazaki, Yosuke
A1  - Wendt, Vivien
A1  - Miyoshi, Y.
A1  - Stolle, Claudia
A1  - Siddiqui, Tarique Adnan
A1  - Kervalishvili, Guram N.
A1  - Laštovička, J.
A1  - Kozubek, M.
A1  - Ward, W.
A1  - Themens, D. R.
A1  - Kristoffersen, S.
A1  - Alken, Patrick
T1  - September 2019 Antarctic sudden stratospheric warming
BT  - Quasi-6-Day wave burst and ionospheric effects
JF  - Geophysical Research Letters
N2  - An exceptionally strong stationary planetary wave with Zonal Wavenumber 1 led to a sudden stratospheric warming (SSW) in the Southern Hemisphere in September 2019. Ionospheric data from European Space Agency's Swarm satellite constellation mission show prominent 6-day variations in the dayside low-latitude region at this time, which can be attributed to forcing from the middle atmosphere by the Rossby normal mode "quasi-6-day wave" (Q6DW). Geopotential height measurements by the Microwave Limb Sounder aboard National Aeronautics and Space Administration's Aura satellite reveal a burst of global Q6DW activity in the mesosphere and lower thermosphere during the SSW, which is one of the strongest in the record. The Q6DW is apparently generated in the polar stratosphere at 30-40 km, where the atmosphere is unstable due to strong vertical wind shear connected with planetary wave breaking. These results suggest that an Antarctic SSW can lead to ionospheric variability through wave forcing from the middle atmosphere.

Plain Language Summary: A sudden stratospheric warming (SSW) is an extreme wintertime polar meteorological phenomenon occurring mostly over the Arctic region. Studies have shown that Arctic SSW can influence the entire atmosphere. In September 2019, a rare SSW event occurred in the Antarctic region, providing an opportunity to investigate its broader impact on the whole atmosphere. We present observations from the middle atmosphere and ionosphere during this event, noting unusually strong wave activity throughout this region. Our results suggest that an Antarctic SSW can have a significant impact on the whole atmosphere system similar to those due to Arctic events.
KW  - Rossby-normal modes
KW  - nonumiform background configuration
KW  - total electron-content
KW  - large-scale
KW  - planetary-waves
KW  - 5-day waves
KW  - equatorial electrojet
KW  - lower thermosphere
KW  - symmetric modes
KW  - 6.5-Day wave
Y1  - 2020
U6  - https://doi.org/10.1029/2019GL086577
SN  - 0094-8276
SN  - 1944-8007
VL  - 47
IS  - 1
SP  - 1
EP  - 12
PB  - Wiley
CY  - Hoboken
ER  -