Tidal Response of the Ionosphere/Thermosphere System to ENSO and Qbo

Friday, 19 December 2014
Jens Oberheide1, Loren C Chang2, Nirmal Nischal1 and Qian Wu3, (1)Clemson University, Clemson, SC, United States, (2)National Central University, Taoyuan County, Taiwan, (3)NCAR, Boulder, CO, United States
This paper presents El Niño/Southern Oscillation (ENSO) and Quasi-Biennial Oscillation (QBO) signals in TEC tides from COSMIC and infrared cooling rate tides from SABER. The observed tidal variability in the ionosphere and thermosphere is quantitatively connected to ENSO and QBO induced tidal variability in the lower thermosphere and further down to tidal forcing variability derived from MERRA and TRMM satellite data. The results suggest that the TEC tidal response is particularly large during the La Niña phase with up to 50% enhancement depending on the tidal component. As such, global weather phenomena like ENSO substantially modulate the local time and longitudinal structure of the low-latitude ionosphere and the thermospheric energy budget.