Liying Qian, National Center for Atmospheric Research, presents “The Earth’s Thermosphere and Ionosphere System and its Coupling to the Lower Atmosphere“
The Earth’s thermosphere is the atmosphere region from ~ 90 km – 600 km. The sun’s extreme ultraviolet radiation ionizes the thermosphere and creates the ionosphere. The neutral and plasma densities are very low but are highly variable driven by both external forcing and internal processes. The external forcing includes the sun’s radiation, electromagnetic energy and energetic particle precipitation from the solar wind and magnetosphere above, and waves/tides from the atmosphere below. The internal processes consist of photochemistry and chemistry, internal dynamics and electrodynamics, and radiative forcing. The amount of the neutrals and plasma, and their variability enable and significantly impact space technology such as low earth orbiting satellites, GPS communication, positioning, and navigation, and future commercial space flights. This presentation provides an overview of the thermosphere and ionosphere system, its coupling with and connection to the lower atmosphere, ground- and space-based observations, numerical modeling of this system, and space weather and space climate.