Evaluation of atmospheric 3-day waves as a source of day-to-day variation of the ionospheric longitudinal structure

These observations reveal a similar to 3-day modulation of the h(m)F(2) wavenumber-4 structure viewed in a fixed local time frame during January 30-February 14, 2021.

Simultaneously, similar to 3-day planetary wave activity is discerned from zonal wind observations at similar to 100 km by the Ionospheric Connection Explorer (ICON) Michelson Interferometer for Global High-Resolution Thermospheric Imaging (MIGHTI). This signature is not observed at similar to 180-250 km altitudes, suggesting the dissipation of this wave below the F-region. We propose that the 3-day variation identified in h(m)F(2) is likely caused by the planetary wave-tide interaction through the E-region dynamo.