A portion of the energy and momentum from particles and electromagnetic fields released by the Sun arrive in the Earth’s magnetosphere and are eventually absorbed by the Earth’s ionosphere. The ionosphere has thus been regarded as serving a load function in the Sun-Earth system. Nevertheless, the polar ionosphere is a dynamic medium that evaporates plasmas and generates parallel potentials along B as well as field-aligned currents. The ionosphere determines by itself the onset timing of the substorms arising out of arcs. Abstracts regarding all aspects of a dynamic ionosphere of Earth, including effects on the atmospheric electricity, are welcome in this session. Discussion of observations, experiments, and modeling relevant to the dynamic ionosphere is encouraged.