Magnetosphere as a Turbulent Wake

Charlista: Marina Stepanova - Universidad de Santiago

Resumen: Significant accumulated evidence indicates that the magnetosphere of the Earth can be considered as a turbulent wake formed by the solar wind behind the Earth. The presence of turbulence observed in many magnetospheric regions constrains the repertoire of methods to describe such plasmas, leaving the balance of total - plasma, magnetic, and dynamic - pressure at large scales as one of the most important conditions for the correct description of magnetospheric dynamics. Any local violation of the conservation of total pressure would alter plasma transport and lead to an increase in geomagnetic activity. We have recently conjectured that, despite turbulence, the plasma in the inner magnetosphere is in magnetostatic equilibrium, and plasma pressure gradients determine the configuration of currents. In turn, the close Region 1 field-aligned currents generates the dawn-dusk electric field, which defines the largest scale of magnetospheric turbulence. Therefore, both plasma pressure and turbulence play a significant role in the dynamics of the magnetosphere, and should be studied in a self-consistent way. Results of the CLUSTER and THEMIS measurements show how the turbulence in the magnetosphere self-consisnently responds to the changes of the solar wind parameters.