On the variability of the semidiurnal solar and lunar tides of the equatorial electrojet during sudden stratospheric warmings
The variabilities of the semidiurnal solar and lunar tides of the equatorial electrojet (EEJ) are investigated during the 2003, 2006, 2009 and 2013 major sudden stratospheric warming (SSW) events in this study. For this purpose, ground-magnetometer recordings at the equatorial observatories in Huanc...
Saved in:
Published in | Annales geophysicae (1988) Vol. 36; no. 6; pp. 1545 - 1562 |
---|---|
Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
Katlenburg-Lindau
Copernicus GmbH
23.11.2018
Copernicus Publications |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | The variabilities of the semidiurnal solar and lunar tides of the equatorial
electrojet (EEJ) are investigated during the 2003, 2006, 2009 and 2013 major
sudden stratospheric warming (SSW) events in this study. For this purpose, ground-magnetometer recordings
at the equatorial observatories in Huancayo and Fúquene are utilized.
Results show a major enhancement in the amplitude of the EEJ semidiurnal
lunar tide in each of the four warming events. The EEJ semidiurnal solar
tidal amplitude shows an amplification prior to the onset of warmings, a
reduction during the deceleration of the zonal mean zonal wind at
60∘ N and 10 hPa, and a second enhancement a few days after the
peak reversal of the zonal mean zonal wind during all four SSWs. Results also
reveal that the amplitude of the EEJ semidiurnal lunar tide becomes
comparable or even greater than the amplitude of the EEJ semidiurnal solar
tide during all these warming events. The present study also compares the EEJ
semidiurnal solar and lunar tidal changes with the variability of the
migrating semidiurnal solar (SW2) and lunar (M2) tides in neutral temperature
and zonal wind obtained from numerical simulations at E-region heights. A
better agreement between the enhancements of the EEJ semidiurnal lunar tide
and the M2 tide is found in comparison with the enhancements of the EEJ
semidiurnal solar tide and the SW2 tide in both the neutral temperature and
zonal wind at the E-region altitudes. |
---|---|
ISSN: | 1432-0576 0992-7689 1432-0576 |
DOI: | 10.5194/angeo-36-1545-2018 |