Effect of Semidiurnal Lunar Tides Modulated by Quasi‐2‐Day Wave on Equatorial Electrojet during Three Sudden Stratospheric Warming Events

2021 ◽  
Author(s):  
Yaxian Li ◽  
Gang Chen ◽  
Shaodong Zhang ◽  
Wanlin Gong ◽  
Zheng Ma ◽  
...  
Keyword(s):  
Equatorial Electrojet ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Lunar Tides

scholarly journals On the variability of the semidiurnal solar and lunar tides of the equatorial electrojet during sudden stratospheric warmings

2018 ◽  
Author(s):  
Tarique A. Siddiqui ◽  
Astrid Maute ◽  
Nick Pedatella ◽  
Yosuke Yamazaki ◽  
Hermann Lühr ◽  
...  
Keyword(s):  
Zonal Wind ◽  
Equatorial Electrojet ◽  
Stratospheric Warming ◽  
Tidal Amplitude ◽  
Lunar Tide ◽  
Sudden Stratospheric Warming ◽  
Lunar Tides ◽  
Neutral Temperature ◽  
Tidal Changes ◽  
Solar Tide

Abstract. The variabilities of the semidiurnal solar and lunar tide 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, the ground-magnetometer recordings at the equatorial observatories in Huancayo and Fuquene 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 the 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 numerical simulations of the variability of the migrating semidiurnal solar (SW2) and lunar (M2) tide in neutral temperature at ~ 120 km altitude. A better agreement between the enhancements of the EEJ semidiurnal lunar tide and the M2 tide in neutral temperature is observed in comparison with the enhancements of the EEJ semidiurnal solar tide and the SW2 tide in neutral temperature.

Effect of Semidiurnal Lunar Tides Modulated by Quasi-2-Day Wave on Equatorial Electrojet during Three Sudden Stratospheric Warming events

2021 ◽  
Author(s):  
Yaxian Li ◽  
Gang Chen
Keyword(s):  
Lower Thermosphere ◽  
Equatorial Electrojet ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Zonal Winds ◽  
Wave Characteristics ◽  
Lunar Tides ◽  
Time Period ◽  
Mesosphere And Lower Thermosphere ◽  
Good Agreement

<p>We present an analysis of the perturbations and wave characteristics in equatorial electrojet (EEJ) and equatorial zonal winds in the mesosphere and lower thermosphere region during three sudden stratospheric warming (SSW) events, based on the wind observations by two meteor radars in Indonesia and the geomagnetic field observations in India. During three SSWs, the shifting semidiurnal perturbations are consistently observed in the EEJ and accompanied with strong 2-day periodic perturbations simultaneously. The semidiurnal lunar (L2) tidal amplitudes in the EEJ and zonal winds show the prominent enhancements during the episodes of EEJ perturbations. The time-period spectra of the L2 tidal amplitudes in both the EEJ and zonal winds present the obvious quasi-2-day wave (QTDW) amplification with good agreement during these periods. Our results firstly reveal the important contributions of QTDW to EEJ perturbations during SSWs and the semidiurnal lunar tides modulated by QTDW serve as the main forcing agent therein</p>

scholarly journals Effect of sudden stratospheric warming on lunar tidal modulation of the equatorial electrojet

2012 ◽  
Vol 117 (A3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Jaeheung Park ◽  
Hermann Lühr ◽  
Markus Kunze ◽  
Bela G. Fejer ◽  
Kyoung Wook Min
Keyword(s):  
Equatorial Electrojet ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming

scholarly journals On the variability of the semidiurnal solar and lunar tides of the equatorial electrojet during sudden stratospheric warmings

2018 ◽  
Vol 36 (6) ◽  
pp. 1545-1562 ◽  
Author(s):  
Tarique A. Siddiqui ◽  
Astrid Maute ◽  
Nick Pedatella ◽  
Yosuke Yamazaki ◽  
Hermann Lühr ◽  
...  
Keyword(s):  
Zonal Wind ◽  
Equatorial Electrojet ◽  
Tidal Amplitude ◽  
Lunar Tide ◽  
Sudden Stratospheric Warming ◽  
Lunar Tides ◽  
Neutral Temperature ◽  
Tidal Changes ◽  
Solar Tide ◽  
E Region

Abstract. 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.

scholarly journals Upper mesospheric lunar tides over middle and high latitudes during sudden stratospheric warming events

2015 ◽  
Vol 120 (4) ◽  
pp. 3084-3096 ◽  
Author(s):  
J. L. Chau ◽  
P. Hoffmann ◽  
N. M. Pedatella ◽  
V. Matthias ◽  
G. Stober
Keyword(s):  
High Latitudes ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Lunar Tides

scholarly journals Identification of the mechanisms responsible for anomalies in the tropical lower thermosphere/ionosphere caused by the January 2009 sudden stratospheric warming

2019 ◽  
Vol 9 ◽  
pp. A39 ◽  
Author(s):  
Maxim V. Klimenko ◽  
Vladimir V. Klimenko ◽  
Fedor S. Bessarab ◽  
Timofei V. Sukhodolov ◽  
Pavel A. Vasilev ◽  
...  
Keyword(s):  
Electric Field ◽  
Phase Change ◽  
Lower Thermosphere ◽  
Upper Atmosphere ◽  
Electron Content ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Low Latitude ◽  
Plasma Drift ◽  
Solar Tide

We apply the Entire Atmosphere GLobal (EAGLE) model to investigate the upper atmosphere response to the January 2009 sudden stratospheric warming (SSW) event. The model successfully reproduces neutral temperature and total electron content (TEC) observations. Using both model and observational data, we identify a cooling in the tropical lower thermosphere caused by the SSW. This cooling affects the zonal electric field close to the equator, leading to an enhanced vertical plasma drift. We demonstrate that along with a SSW-related wind disturbance, which is the main source to form a dynamo electric field in the ionosphere, perturbations of the ionospheric conductivity also make a significant contribution to the formation of the electric field response to SSW. The post-sunset TEC enhancement and pre-sunrise electron content reduction are revealed as a response to the 2009 SSW. We show that at post-sunset hours the SSW affects low-latitude TEC via a disturbance of the meridional electric field. We also show that the phase change of the semidiurnal migrating solar tide (SW2) in the neutral wind caused by the 2009 SSW at the altitude of the dynamo electric field generation has a crucial importance for the SW2 phase change in the zonal electric field. Such changes lead to the appearance of anomalous diurnal variability of the equatorial electromagnetic plasma drift and subsequent low-latitudinal TEC disturbances in agreement with available observations. Plain Language Summary – Entire Atmosphere GLobal model (EAGLE) interactively calculates the troposphere, stratosphere, mesosphere, thermosphere, and plasmasphere–ionosphere system states and their response to various natural and anthropogenic forcing. In this paper, we study the upper atmosphere response to the major sudden stratospheric warming that occurred in January 2009. Our results agree well with the observed evolution of the neutral temperature in the upper atmosphere and with low-latitude ionospheric disturbances over America. For the first time, we identify an SSW-related cooling in the tropical lower thermosphere that, in turn, could provide additional information for understanding the mechanisms for the generation of electric field disturbances observed at low latitudes. We show that the SSW-related vertical electromagnetic drift due to electric field disturbances is a key mechanism for interpretation of an observed anomalous diurnal development of the equatorial ionization anomaly during the 2009 SSW event. We demonstrate that the link between thermospheric winds and the ionospheric dynamo electric field during the SSW is attained through the modulation of the semidiurnal migrating solar tide.

Sign in / Sign up

Export Citation Format

Share Document