Advances on Upper-Atmosphere Characterization for Geodetic Space Weather Research and Applications

The negative impacts of space weather conditions on modern technologies have become a vital concern over the last decades, as humans increasingly rely on satellite communications, Positioning-Navigation-Timing (PNT), Global Navigation Satellite Systems (GNSS), Earth’s observation and forecasting through in-situ and remote sensing, and countless other applications. This situation underscores the necessity to better understand and predict the effects of Magnetosphere-Ionosphere-Thermosphere (MIT) coupling processes in the near-Earth environment in order to prevent detrimental effects on orbital determination, satellite imaging, and other space- and ground-based technologies (e.g., the delay and bending of radio wave propagation in the ionosphere on GNSS signals and communications, the drag force disturbances on Low Earth orbiting (LEO) satellite trajectories, the power and Internet outages due to intense electric currents induced during geomagnetic storms, etc.). Moreover, the variability of the ozone layer has strong dependence on space weather, and connects the troposphere and the surface temperature variability. The ozone layer is a strong absorber of Solar ultraviolet (UV) radiation and long-wave radiation emitted from the Earth’s surface, and thus it plays a key role in global warming and climate change, which is in turn also affected by human activities such as powerful ground-based radio transmitters.

On the one side, UV and extreme UV (EUV) radiation is mostly absorbed by the thermosphere to create the ionosphere through ionization/dissociation of neutrals. On the other side, the thermosphere and ionosphere are strongly influenced by wave motions from the lower atmosphere, and also by energetic particle precipitation and field‐aligned currents through the magnetosphere and solar wind. Addressing the challenges related to the coupled MIT system requires significant advances in geodetic observations of plasma and neutral density, “compositions”, and “velocities”, observations of energetic particles and “magnetic field perturbations” both in space and on ground, as well as advanced theoretic and numerical modeling capabilities. This collection aims to contribute to a better understanding of Space Weather phenomena within the coupled MIT system, and to the formulation of predictive models of the near-Earth space environment.

In order to better understand and predict the effects of MIT coupling processes in the near-Earth environment we need:
• To characterize and quantify the global modes of MIT variations on diurnal, seasonal, and decadal scales associated with solar/magnetospheric as well as the lower atmosphere forcing and other possible contributors.
• To determine and understand the mechanisms responsible for discrepancies between measurements and predictions by present models, and explore possible avenues to improve the models’ capabilities in space weather predictions.
• To investigate and evaluate the importance of the different coupling processes in the MIT system based on physical laws and principles such as continuity, energy and momentum equations and solving partial differential equations.
• To reveal the peculiarities of MIT dynamics during magnetic storms.

The scope of this collection aims to present the most recent advances, algorithms and methodologies on upper-atmosphere characterization for geodetic space weather research and applications. The articles may be either a full paper or a communication based on your own research in this area, or may be a focused review article on some aspect of the subject.

Keywords: Space Weather, Space Geodesy, Solar-Terrestrial Interactions, Near-Earth Environment, Upper Atmosphere, Magnetosphere-Ionosphere-Thermosphere Coupling

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.