Simulations of solar and lunar tidal variability in the mesosphere and lower thermosphere during sudden stratosphere warmings and their influence on the low-latitude ionosphere

摘要: [1] Whole Atmosphere Community Climate Model (WACCM) simulations are used to investigate solar and lunar tide changes in the mesosphere lower thermosphere (MLT) that occur response sudden stratosphere warmings (SSWs). The average tidal is demonstrated based on 23 moderate strong Northern Hemisphere SSWs. migrating semidiurnal enhanced globally during SSWs, with largest enhancements (∼60–70%) occurring at mid high latitudes Hemisphere. Enhancements (SW2) also up an altitude of 120 km. Above this altitude, SW2 decreases 40–50%, making them smaller a relative sense than tide. Changes nonmigrating tides are, average, generally small only exhibit greater 20% diurnal zonal wave number 0 (D0) westward propagating 1 (SW1). D0 decreased by ∼20–30% low latitudes, while SW1 exhibits similar magnitude enhancement both hemispheres. attributed combination mean winds, ozone forcing SW2, nonlinear planetary wave-tide interactions. We further influence generating perturbations latitude ionosphere SSWs using WACCM-X drive ionosphere-electrodynamics model. For maximum minimum simulations, equatorial vertical plasma drift velocity observations when included simulations. However, removed from unclear characteristic behavior seen no longer apparent. Our results thus indicate importance variability especially for coupling between ionosphere.