Analysis of ionospheric datasets to identify signatures with periods matching atmospheric planetary waves.

Atmospheric planetary waves play a role in introducing variability to the low-latitude ionosphere. To better understand this coupling, this study investigates times when oscillations seen in both atmospheric planetary waves and ionospheric datasets have similar periodicities. The planetary wave dataset used are temperature observations made by Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). These highlight periods during which 2-Day westward propagating wavenumber 3 waves are evident in the mesosphere and lower thermosphere. The ionospheric dataset is Total Electron Content (TEC), which is used to identify periods during which the ionosphere appears to respond to the planetary waves. Data from KP and F10.7 indices are used to determine events that may be of external origin. A 17-year timespan from 2002 to 2018 is used for this analysis so that both times of solar minimum and maximum can be studied. To extract the periods of this collection of data a Morlet Wavelet analysis is used, along with thresholding to indicate events when similar periods are seen in each dataset. We then determine trends that can lead to verification of previous assumptions and new discoveries. This study catalogues a large number of events during which there is obvious planetary wave and ionospheric coupling. These events are then investigated in greater detail to improve the understanding of the dynamics that play a role in this coupling.