Hi Rainer,
Thanks for your comments.

> > > (d) Simulations do not include anisotropic turbulence (to my knowledge),
> > > although there is observational evidence that most of the "ordered" fields
> > > seen in radio and FIR polarisation are in fact anisotropic turbulent (or
> > > tangled regular) ones.
> > 
> > Do you mean a striated field?
> 
> "Striated field" is a sloppy term that is used by a few colleagues. Most
> colleagues prefer "anisotropic random field" which is physically founded; it
> was defined by Anvar and Mitia many decades ago.

Yes, striated is only used by some galactic people, but it refers to a
special form of anisotropy that is caused by the shear. Anisotropy is very
general. It is also caused by the magnetic field itself: the direction of
a net field within a subvolume affects all smaller scales. Anisotropies
are also caused by density stratification the rotation even without shear.

> > But this is something that should come out
> > and is not something to put in. But we aren't sure whether this aspect is
> > really in disagreement with observations. Some simulations start with a
> > strong field, so those are then initially more anisotropic perhaps.
> 
> Maybe. My point was that small-scale anisotropic random fields need to be
> distinguished from large-scale regular fields. The observed strong field
> anisotropy was not yet discussed in papers on MHD simulations. What would be
> needed is e.g. the power spectrum of the coherent fields (i.e. those
> preserving their direction) and/or the frequency of the scales of field
> reversals.

Yes, spectra would be a good way to quantify the magnetic field. You
are here probably thinking of separate spectra along and perpendicular
to the shear.

> > > - Section 6.2: As I wrote in my various reviews, the result of a
> > > predominantly nonaxisymmetric field in M81 from 1989 is most probably
> > > incorrect. That result was based on RMs between 6cm and 20cm, where
> > > the 20cm
> > > data are strongly affected by Faraday depolarisation. New data have been
> > > obtained, but results are not yet available.
> > 
> > So what do you suggest we do? We have now again referred to Beck+19, but
> > there you just write that M81 and M83 have perhaps BSS.
> 
> Right. I was too polite in the 2019 paper but should have been clearer.
> Maybe you could replace "is known to be predominantly nonaxisymmetric" by
> "is possibly predominantly nonaxisymmetric".

OK, we have done this now.
Cheers, Eva & Axel