Cross scale energy transport in space plasmas: Application to the Magnetopause Boundary

As space plasmas are highly collisionless and involve several temporal and spatial scales, understanding the physical mechanisms responsible for energy transport between these scales is a challenge. Ideally, to study cross-scale space plasma processes, simultaneous multispacecraft measurements in three different scales (fluid, ion and electron) would be required together with adequate instrumental temporal resolution. In this chapter we discuss cross-scale energy transport mechanisms mainly focusing on velocity shear driven Kelvin–Helmholtz instability and resulting secondary instabilities and processes, e.g. magnetic reconnection, kinetic magnetosonic waves, and kinetic Alfvén waves/mode conversion.