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The extent to which angular momentum transport in accretion discs isprimarily local or non-local and what determines this is an important avenue ofstudy for understanding accretion engines. Taking a step along this path, weanalyze simulations of the magnetorotational instability (MRI) by calculatingenergy and stress power spectra in stratified isothermal shearing boxsimulations in several new ways. We divide our boxes in two regions, disc andcorona where the disc is the MRI unstable region and corona is the magneticallydominated region. We calculate the fractional power in different quantities,including magnetic energy and Maxwell stresses and find that they are dominatedby contributions from the lowest wave numbers. This is even more dramatic forthe corona than the disc, suggesting that transport in the corona region isdominated by larger structures than the disc. By calculating averaged powerspectra in one direction of $k$ space at a time, we also show that the MRIturbulence is strongly anisotropic on large scales when analyzed by thismethod, but isotropic on small scales. Although the shearing box itself ismeant to represent a local section of an accretion disc, the fact that thestress and energy are dominated by the largest scales highlights that thelocality is not captured within the box. This helps to quantify the intuitiveimportance of global simulations for addressing the question of locality oftransport, for which similar analyses can be performed.

On characterizing nonlocality and anisotropy for the magnetorotational instability