The Short and Long Timescale Responses of the Inner Magnetospheric EMIC Waves to the Solar Wind Dynamic Pressure

The causal relationships between solar wind dynamic pressure and Electromagnetic Ion‐Cyclotron (EMIC) , , waves at are investigated with transfer entropy at short ( min) and long ( min) timescales. The short timescale responses of and bands around noon can be attributed to the magnetospheric compression leading to adiabatic heating and anisotropy. The long timescale responses of band around noon, band around noon and dusk, and band in the afternoon may be attributed to storm/substorm ion injections from the magnetotail that are adiabatically heated and anisotropized, and drift westward toward dusk and noon where they would mix with cold ions, leading to the growth of the EMIC waves at min while their drift echoes lead to the EMIC wave growth at min. The periodicities of the injected ions are consistent with the magnetic drift of ions having energies of 100–200 keV.