  In magnetohydrodynamic (MHD) turbulence, the large-scale magnetic field sets
a preferred local direction for the small-scale dynamics, altering the
statistics of turbulence from the isotropic case. This happens even in the
absence of a total magnetic flux, since MHD turbulence forms randomly oriented
large-scale domains of strong magnetic field. It is therefore customary to
study small-scale magnetic plasma turbulence by assuming a strong background
magnetic field relative to the turbulent fluctuations. This is done, for
example, in reduced models of plasmas, such as reduced MHD, reduced-dimension
kinetic models, gyrokinetics, etc., which make theoretical calculations easier
and numerical computations cheaper. Recently, however, it has become clear that
the turbulent energy dissipation is concentrated in the regions of strong
magnetic field variations. A significant fraction of the energy dissipation may
be localized in very small volumes corresponding to the boundaries between
strongly magnetized domains. In these regions the reduced models are not
applicable. This has important implications for studies of particle heating and
acceleration in magnetic plasma turbulence. The goal of this work is to
systematically investigate the relationship between local magnetic field
variations and magnetic energy dissipation, and to understand its implications
for modeling energy dissipation in realistic turbulent plasmas.
