  Intercluster medium is expected to be turbulent with turbulence being
superAlfvenic at large scales. Magnetic fields substantially modify the
turbulent cascade when the turbulence reaches the scales at which the
fluctuation velocity gets less than the Alfven velocity. At those scales it is
possible to consider three cascades, of fast, slow and Alfven modes with little
energy exchange between them. As Alfvenic and slow modes are anisotropic they
marginally scatter and accelerate cosmic rays, while fast modes dominate the
processes. However, in the presence of cosmic rays the turbulence is modified
as cosmic rays transfer the energy of compressible motions (i.e. slow and fast
modes) from large scales to the scale of cosmic ray Larmor radius. This results
in generation of a new small-scale Alfvenic component which is not a part of
the ordinary MHD cascade. This component does scatter and accelerate cosmic
rays. In addition, magnetic reconnection in turbulent medium accelerates cosmic
rays. The complexity of the intracluster turbulence calls for observational
studies. A new technique Velocity Coordinate Spectrum (VCS) is particularly
promising for studies of velocity fluctuations with a new generation of X-ray
observatories.
