地球同步轨道相对论电子微分通量的动态预报模型

Dynamic Prediction Model of Relativistic Electron Differential Fluxes at the Geosynchronous Orbit

地球同步轨道区域充满能量高达MeV的高能电子,其对航天器威胁极大.电子微分通量预报有助于及时有效地预警高能电子事件,降低高能电子对航天器造成的危害.本文以此为背景提出了一种基于经验正交函数(EOF)方法的地球同步轨道相对论电子微分通量预报模型.该模型利用太阳风参数及地磁指数拟合后一天的电子通量EOF系数,结合EOF基函数给出后一天中大于2 MeV电子微分通量预报.对2003年1月至2006年6月的样本测试结果表明,该模型可以重构出电子微分通量的真实变化,给出较好的5 min微分通量预报,其平均预报效率达到67%左右.

The Empirical Orthogonal Function （EOF） analysis is applied to develop an empirical model to predict relativistic electron fluxes at the geostationary orbit. This model uses the solar wind parameters and geomagnetic index to forecast the EOF-coefficient, and then gives the 5 min prediction results of relativistic electron differential fluxes during the coming day according to the EOF base function. By comparing with the original relativistic electron data obtained by GOES 10 from January 2003 to June 2006, it is found that the model is capable of approximately reconstructing the real changes of relativistic electron fluxes and of effectively forecasting their 5 min variations. The mean prediction efficiency of this model is 67%.