  We report on a detailed radiative transfer modeling of the observed
scattering polarization in the H-alpha line, which allows us to infer
quantitative information on the magnetization of the quiet solar chromosphere.
Our analysis suggests the presence of a magnetic complexity zone with a mean
field strength <B> > 30 G lying just below the sudden transition region to the
coronal temperatures. The chromospheric plasma directly underneath is very
weakly magnetized, with <B> ~ 1 G. The possible existence of this abrupt change
in the degree of magnetization of the upper chromosphere of the quiet Sun might
have large significance for our understanding of chromospheric (and, therefore,
coronal) heating.
