What cause partial ring current during geomagnetic storm event?
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The partial ring current during a geomagnetic storm event is caused by a sustained enhancement of the convection electric field . This enhanced convection electric field moves plasma Earth-ward, energizing it. When the convection electric field is reduced, the particles become trapped and a symmetric ring current is formed . Substorms, which are accompanied by the injection of energetic particles, also contribute to the storm-time ring current, although the extent of their contribution is still a matter of debate . The partial ring current is predominantly located in the dusk sector, peaking in the evening magnetic local time . It forms in the early main phase of the storm, increases gradually until the storm reaches its minimum intensity, and then quickly decreases during the recovery phase . The contribution of the partial ring current weakens as the storm intensity increases .
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| Papers (5) | Insight |
|---|---|
| During some storms with positive or barely negative IMF, the model holds the ring current energy steady instead of allowing it to decrease through normal loss processes. | |
| Both substorms and enhanced convection contribute to the buildup of the storm-time ring current during a geomagnetic storm event. | |
| The partial ring current during geomagnetic storm events is primarily caused by the asymmetry of H depression and forms in the dusk sector. | |
25 Citations | The partial ring current during a geomagnetic storm event is primarily caused by a sustained enhancement of the convection electric field. |
| The study found that the substorm process contributes a significant amount of energy to the ring current, which may cause partial ring current during geomagnetic storm events. |
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