地球同步轨道高能电子通量预报方法研究

统计分析了GOES卫星测量得到的E > 2MeV能道电子通量与地磁Ap指数及太阳风数据的关系, 构建了基于径向基函数RBF的神经网络模型框架, 对GOES-12卫星所处的地球同步轨道高能电子通量进行提前1天的预报, 其对2008-2010年数据预测的效果较好. 另外, 发现在GOES-12卫星观测的E >2MeV能道高能电子达到108 cm-2·d-1·sr-1以上时, FY-2D卫星的测量数据同时达到108 cm-2·d-1·sr-1以上的比例达到90%左右. 通过对FY-2D卫星E >2MeV能道电子通量与GOES卫星E>2MeV电子通量的相关性分析, 建立了FY-2D卫星高能电子预报模型, 预报结果与实测通量符合较好. 

Approach for Predicting the Energetic Electron Flux in Geosynchronous Earth Orbit

Geosynchronous Earth Orbit (GEO) is in the earth's outer radiation belts, where energetic electrons are enriched. The flux of energetic electron will surge after the geomagnetic disturbance, which is one of the causes for the failure of satellites. So, it is important to predict the electron flux on the geosynchronous orbit in order to prevent the satellite from harming. As the enhancement of electron flux is controlled by many conditions and its temporal and spatial evolution is complex, it needs to analyze various data to make the prediction model. In this work, energetic flux data from GOES-12 was statistically analyzed together with geomagnetic A_p index and solar wind velocity and combination of input parameters was determined. An artificial neural network based model was built and trained with the data mentioned above. The prediction of electron flux of E >2MeV one day ahead has been made and the result was good that the prediction efficiencies were 0.766, 0.808 and 0.882 for the year of 2008, 2009 and 2010, which is a little better than other models. The prediction for electron flux of FY-2D satellite was made applying the GOES-12 prediction result by analyzing the flux related characteristics. The statistics showed that the E >2MeV electron flux measurement of the two kinds of satellite become similar when the flux was above 108 cm-2·d-1·sr-1. Because the deep charge effect become significant when E >2MeV electron flux exceed 108 cm-2·d-1·sr-1, the energetic electron alert for FY-2D satellite was made with the result by GOES prediction and got good result.