Allsky NICER and NICEST extinction maps based on the 2MASS near-infrared
  survey
  Extinction remains one of the most reliable methods of measuring column
density of nearby Galactic interstellar clouds. The current and ongoing
near-infrared surveys enable the mapping of extinction over large sky areas. We
produce allsky extinction maps using the 2MASS near-infrared survey. We use the
NICER and NICEST methods to convert the near-infrared colour excesses to
extinction estimates. The results are presented in Healpix format at the
resolutions of 3.0, 4.5, and 12.0 arcmin. The main results of this study are
the calculated J-band extinction maps. The comparison with earlier large-scale
extinction mappings shows good correspondence but also demonstrates the
presence of resolution-dependent bias. A large fraction of the bias can be
corrected by using the NICEST method. For individual regions, best extinction
estimates are obtained by careful analysis of the local stellar population and
the use of the highest resolution afforded by the stellar density. However, the
uniform allsky maps should still be useful for many global studies and as the
first step into the investigation of individual clouds.
