A central theme of the CGS science investigation, enabled by the MAGE model, is the importance of mesoscale processes and cross-scale coupling in emergent global-scale dynamics.
There are many examples of such mesoscale processes acting throughout stormtime geospace. Some examples are indicated with yellow arrows in the image at the top. They include, but are not limited to:
- Build-up of the ring current by bursty bulk flows and localized energetic particle injections.
- Polar cap density structures, such as tongues of ionization and patches, that present a major space weather hazard due to their detrimental effect on communications. They also present a major scientific and modeling challenge as part of the global plasma circulation process involving the ionosphere, the plasmasphere and the inner magnetosphere, sometimes referred to as the geospace plume (Foster et al., 2020)
- Kelvin-Helmholtz waves on the magnetospheric boundary. These waves drive ultra-low frequency oscillations in the inner magnetosphere that are important for shaping the response of radiation belts to geospace storms. These waves are also believed to be a major mechanism for solar wind plasma entry into the magnetosphere (Wing et al., 2014)
- Atmospheric gravity waves exert forcing on and precondition the ionosphere and thermosphere (Qian and Yue, 2017), and thus can affect their responses to geospace storms. At the same time, storm-time effects in the ionosphere-thermosphere system introduce changes in the circulation and may affect the breaking and deposition of energy and momentum by gravity waves and tides. Thus it is important to investigate the change of global mean flow and lower atmosphere waves, and their interaction during storms and of the physical mechanisms that determine this interaction (Hagan et al., 2015; Pedatella, 2016).