  We propose a set of quick and easy approximate characteristic variables for
higher-order reconstructions of shock capturing schemes for
magnetohydrodynamics (MHD). Numerical experiments suggest that the
reconstructions using the approximate characteristic variables are more robust
than those using the conservative or primitive variables, while their
computational efficiencies are comparable. The approximate characteristic
variables are simple compared to the full characteristic variables for MHD, and
can be a practical choice of reconstruction variables.

Computational Physics