magnetospheric substorm

magnetospheric substorm

[mag′nēd·ə‚sfir·ik ′səb‚stȯrm] (geophysics) A disturbance of particles and magnetic fields in the magnetosphere; occurs intermittently, lasts 1 to 3 hours, and is accompanied by various phenomena sensible from the earth's surface, such as intense auroral displays and magnetic disturbances, particularly in the nightside polar regions.