Propagation Characteristics of Electromagnetic Ion Cyclotron (EMIC) Waves
 

EMIC waves have long been known to play a critical role in both radiation belt and ring current dynamics. EMIC waves are generated near the equator and propagate parallel to the background magnetic field toward higher latitudes and even down to the ground. The propagation of waves generated near the equator is important to understand the effect of waves on particle dynamics. A long history of ground observations has provided a solid scientific understanding of EMIC waves which are also known as Pc1-2 waves. However, satellite measurements of EMIC waves often show different characteristics from ground observations. For example, EMIC waves observed on the ground appear to persist over longer hours while only the snapshot of such waves is observed by fast-moving spacecraft. Their spectral features such as wave power and polarization senses often change during propagation. We discuss the statistical characteristics of the coincidence of EMIC waves using a magnetically conjugate ground and satellite magnetometer pair.