Classified prediction of geomagnetic disturbance caused by coronal mass ejection

The characteristics of accelerating coronal mass ejection (CME) and decelerating CME happening during 1997-2003 are analyzed. Prediction tests are made for geomagnetic disturbance events caused by the .gradually accelerating CME-associated interplanetary shock waves and the decelerating CME-associated interplanetary shock waves, which can be identified by interplanetary scintillation (IPS) observation during 1997-2003. New membership functions and new correctional item of onset time of geomagnetic disturbances are respectively constituted for two kinds of CME. The main results are: for the onset time of the geomagnetic disturbance in the accelerating CME, the relative error between the observation, T_obs, and the prediction, T_pre, ΔT_pre/T_obs ≤ 10% for 21.86% of all events, ≤ 30% for 78.13% and ≥ 50% for only 9.36%; for the decelerating CME, ΔT_pre/T_obs ≤ 10% for 25.00% of all events, ≤ 30% for 84.37% and ≥ 50% for only 3.13%. These results show that the method has good feasibility for the geomagnetic disturbance predictions.