  Using the Subaru Telescope, we have obtained multiple near-infrared spectra
of the cool brown dwarf, SDSS 1624+00, in search of spectral variability in an
80 minute time span. We have found the suspected variability of water vapor
absorption throughout the observations, which requires confirmation by a longer
time baseline. After coadding the spectra, we have obtained a high-quality
spectrum covering 1.05 to 1.8 um. Three kinds of spectral indicators, the water
vapor bands, methane band, and KI lines in J band, suggest that SDSS 1624+00 is
warmer and dustier than Gl 229B.
