Current Status of Inner Magnetosphere and Radiation Belt Modeling

Simulation models have been established to study the responses of particles and fields in the inner magnetosphere and radiation belts to various solar wind inputs. The goal is to gain understanding that leads to prediction of the variabilities of the radiation environment and electromagnetic disturbances. In this paper, an overview of different approaches of modeling the inner magnetosphere will be given. We will focus on physical models with emphasis on energetic ions and electrons in the radiation belts. We will present the current status of simulation studies with test-particle technique, diffusion approach, and convection–diffusion method. Suggestions on model improvement will be discussed as well. Since each modeling approach has its own applications, advantages, and limitations, our goal is to provide researchers, who are interested in inner magnetosphere and radiation belt modeling, useful information to select the model or approach that suits their needs.