Recent Advancements and Remaining Challenges Associated With Inner Magnetosphere Cross-Energy/Population Interactions (IMCEPI)

The geospace inner magnetosphere, within about 10 Earth radii, contains various plasma populations with energy from a few electron volts to megaelectron volts and plays important roles in regulating the energy density of the magnetosphere, the magnetic field configuration, and wave dynamics. As an integrated part of the magnetosphere, the inner magnetosphere region also ties to other regions and can change the global geospace circulation. Therefore, understanding both internal and external cross-energy/population interactions can help further our knowledge of the inner magnetosphere dynamics and nonlinear feedback processes. In view of this, in the past 5 years (2014–2018), the Geospace Environment Modeling (GEM) Focus Group “inner magnetosphere cross-energy/population interactions (IMCEPI)” has gathered and boosted community-wide interactions among observation, simulation, and modeling studies. This commentary reports some major accomplishments of the interactive inner magnetosphere community that were advanced by the IMCEPI Focus Group discussions and layouts remaining challenges that need to be carried on.