Modulation of the SE2 Tide in the MLT Region by the MJO Phenomenon

Based on Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED)/Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperature observations and the Real-Time Multivariate Madden–Julian Oscillation (MJO) Index, this study provides the first analysis of the non-migrating SE2 temperature tide at daily resolution and its response to the MJO phenomenon across phases 1–8 between ±45° latitude from 2003 to 2012, in the Mesosphere and Lower Thermosphere (MLT) region. The main findings are as follows: (a) The SE2 tide exhibits pronounced variations with MJO phase across all seasons above 100 km altitude, accompanied by clear phase shifts under different MJO conditions. (b) The SE2 response to the MJO is more evident during solstices than during equinoxes, with the more evident modulation occurring in the June solstice. (c) The asymmetric component of the SE2 response dominates over the symmetric component throughout the seasons. In summary, the daily resolved SE2 tide, particularly its phase behavior, plays a key role in shaping the seasonal characteristics and symmetric patterns in the MLT region under MJO forcing.