The Galactic extinction and reddening from the South Galactic Cap U-band
  Sky Survey: u band galaxy number counts and $u-r$ color distribution
  We study the integral Galactic extinction and reddening based on the galaxy
catalog of the South Galactic Cap U-band Sky Survey (SCUSS), where $u$ band
galaxy number counts and $u-r$ color distribution are used to derive the
Galactic extinction and reddening respectively. We compare these independent
statistical measurements with the reddening map of \citet{Schlegel1998}(SFD)
and find that both the extinction and reddening from the number counts and
color distribution are in good agreement with the SFD results at low extinction
regions ($E(B-V)^{SFD}<0.12$ mag). However, for high extinction regions
($E(B-V)^{SFD}>0.12$ mag), the SFD map overestimates the Galactic reddening
systematically, which can be approximated by a linear relation $\Delta E(B-V)=
0.43[E(B-V)^{SFD}-0.12$]. By combing the results of galaxy number counts and
color distribution together, we find that the shape of the Galactic extinction
curve is in good agreement with the standard $R_V=3.1$ extinction law of
\cite{ODonnell1994}.
