TY  - JOUR
A1  - Siddiqui, Tarique Adnan
A1  - Stolle, Claudia
A1  - Lühr, Hermann
T1  - Longitude-dependent lunar tidal modulation of the equatorial electrojet during stratospheric sudden warmings
JF  - Journal of geophysical research : Space physics
N2  - The effects of coupling between different layers of the atmosphere during Stratospheric Sudden Warming (SSW) events have been studied quite extensively in the past fewyears, and in this context large lunitidal enhancements in the equatorial ionosphere have also been widely discussed. In this study we report about the longitudinal variabilities in lunitidal enhancement in the equatorial electrojet (EEJ) during SSWs through ground and space observations in the Peruvian and Indian sectors. We observe that the amplification of lunitidal oscillations in EEJ is significantly larger over the Peruvian sector in comparison to the Indian sector. We further compare the lunitidal oscillations in both the sectors during the 2005-2006 and 2008-2009 major SSW events and during a non-SSW winter of 2006-2007. It is found that the lunitidal amplitude in EEJ over the Peruvian sector showed similar enhancements during both the major SSWs, but the enhancements were notably different in the Indian sector. Independent from SSW events, we have also performed a climatological analysis of the lunar modulation of the EEJ during December solstice over both the sectors by using 10years of CHAMP magnetic measurements and found larger lunitidal amplitudes over the Peruvian sector confirming the results from ground magnetometer observations. We have also analyzed the semidiurnal lunar tidal amplitude in neutral temperature measurements from Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) at 110km and found lesser longitudinal variability than the lunitidal amplitude in EEJ. Our results suggest that the longitudinal variabilities in lunitidal modulation of the EEJ during SSWs could be related to electrodynamics in the E region dynamo.
KW  - SSW
KW  - vertical coupling
KW  - equatorial electrojet
KW  - lunar tide of EEJ
Y1  - 2017
U6  - https://doi.org/10.1002/2016JA023609
SN  - 2169-9380
SN  - 2169-9402
VL  - 122
IS  - 3
SP  - 3760
EP  - 3776
PB  - American Geophysical Union
CY  - Washington
ER  -