  We develop an inversion technique of annual scattered light curves to sketch
a two-dimensional albedo map of exoplanets in face-on orbits. As a test-bed for
future observations of extrasolar terrestrial planets, we apply this mapping
technique to simulated light curves of a mock Earth-twin at a distance of 10 pc
in a face-on circular orbit. A primary feature in recovered albedo maps traces
the annual mean distribution of clouds. To extract information of other surface
types, we attempt to reduce the cloud signal by taking difference of two bands.
We find that the inversion of reflectivity difference between 0.8-0.9 and
0.4-0.5 micron bands roughly recover the continental distribution, except for
high latitude regions persistently covered with clouds and snow. The inversion
of the reflectivity difference across the red edge (0.8-0.9 and 0.6-0.7 micron)
emphasizes the vegetation features near the equator. The planetary obliquity
and equinox can be estimated simultaneously with the mapping under the presence
of clouds. We conclude that the photometric variability of the scattered light
will be a powerful means for exploring the habitat of a second Earth.
