[P-EM13] Coupling Processes in the Atmosphere-Ionosphere System

[PEM13-18] Quantifying Space Weather and Lower Atmospheric Forcing on the Global Ionospheric State Using Information Theory

★Invited Papers

*Xing Meng¹、Olga Verkhoglyadova¹ (1.Jet Propulsion Laboratory, California Institute of Technology)

To better understand the global ionospheric response to external drivers, we apply entropy-based information theory to quantify contributions of solar, interplanetary, and lower atmospheric drivers to the global ionospheric state. We specify the global ionospheric state using the total electron content (TEC) data provided by the Global Ionospheric Map (GIM). We compute the normalized transfer entropy on 18 years of TEC, F10.7, solar wind, and lower atmospheric state data to find out the predictive information transfer from present driver parameters to the TEC at various future times. Our results indicate that the solar extreme ultraviolet (EUV) irradiance dominates the information transfer within three days into the future, while the lower atmospheric migrating tidal sources dominate beyond three days into the future. Based on the maximum information transfer from individual drivers, the lower atmospheric migrating tidal sources contribute most to the global ionospheric state. The solar EUV irradiance and tropospheric deep convection are secondary drivers with comparable contributions at about half of the contribution from migrating tidal sources. The interplanetary driving contributes the least to the global ionospheric state during both geomagnetic storm and quiet time, even though the contribution from the interplanetary magnetic field can enhance four to six times during geomagnetic storm time than quiet time. Our work is the first systematic quantification of the contributions from the solar, interplanetary, and lowers atmospheric drivers to the global ionospheric state using transfer entropy.