The paper reviews studies of the dynamics of relativistic electrons in the geosynchronous region. It lists the physical processes that lead to the acceleration of electrons filling the outer radiation belt. As one of the space weather factors, high-energy electron fluxes pose a serious threat to the operation of satellite equipment in one of the most populated orbital regions. Necessity is emphasized for efforts to develop methods of forecasting the situation in this part of the magnetosphere, possible predictors are listed, and their classification is given. An example of a predictive model for forecasting relativistic electron flux with a lead time of 1–2 days is proposed. Some questions of practical organization of prediction are discussed; the main objec-tives of short-term, medium-term, and long-term forecasts are listed.
radiation belts, relativistic electrons, forecast, magnetosphere, solar wind.
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