El Niño–Southern Oscillation effect on ionospheric tidal/SPW amplitude in 2007–2015 FORMOSAT-3/COSMIC observations

Abstract

This study examines the influence of the El Niño-Southern Oscillation (ENSO) on the ionospheric total electron content (TEC) diurnal eastward 3 (DE3) and stationary planetary wave 4 (SPW4) which are the major components of the ionospheric wave-4 longitudinal structure. The TEC is the integration of electron density from 200 to 800 km sounded by the GPS radio occultation experiment onboard the FORMOSAT-3/COSMIC satellites during the period of January 2007-December 2015. The results show that the TEC DE3 and SPW4 amplitudes respond to the ENSO signature in the thermospheric wind DE3 in the Northern Hemisphere during the lower-solar-activity period. The contribution of the ENSO cold phase in 2010 and 2011 to the quasi-biennial oscillation in the TEC DE3 and SPW4 amplitudes is not negligible.

Numerical Solution of the Atmospheric Perturbations Triggered by Persistent Lithospheric Vibrations

“…The lithosphere-atmosphere coupling has been observed and widely reported in many previous studies. The coupling phenomena can be detected during earthquakes and volcanic eruptions [4,11,[58][59][60]78]. However, the coupling phenomena too complex to be simulated comprehensively.…”

Global Distribution of Persistence of Total Electron Content Anomaly

“…The high persistence of positive TEC anomaly in the longitudinal band between 105 • E and 150 • E in the Southern Hemisphere corresponds to the valley between the two peaks of ionospheric electron density over South Asia and the Central Pacific Ocean [24]. The regional persistence should be irrelevant to the ionospheric dynamo driven by global atmospheric tides from the lower atmosphere that result in the ionospheric four-peak structure [25,26].…”

Investigating the Spatio-Temporal Distribution of Gravity Wave Potential Energy over the Equatorial Region Using the ERA5 Reanalysis Data

“…This ocean-stratosphere-mesosphere coupling is very important to explain the enhancement of mesospheric wave activity during El Niño episodes. Its effect may further propagate into the ionosphere modifying the ionospheric morphology (e.g., [77][78][79][80]).…”

“…In addition, the enhanced gravity waves may propagate further into the thermosphere directly or indirectly via secondary wave generation, under favorable conditions, and influence both the neutral atmosphere and ionized particles, i.e., the ionosphere. Many papers have reported the correlation between the El Niño-Southern Oscillation (ENSO) and thermospheric tides, ionospheric E region scintillations, and total electron content (TEC) fluctuations (e.g., [77][78][79][80]), indicating dynamic ocean-atmosphere coupling via gravity waves.…”