  We simulate the light variability of the Ap star epsUMa using the observed
surface distributions of Fe, Cr, Ca, Mn, Mg, Sr and Ti obtained with the help
of Doppler Imaging technique. Using all photometric data available we specified
light variations of epsUMa modulated by its rotation from far UV to IR. We
employed the LLmodels stellar model atmosphere code to predict the light
variability in different photometric systems. The rotational period of epsUMa
is refined to 5d088631(18). It is shown that the observed light variability can
be explained as a result of the redistribution of radiative flux from the UV
spectral region to the visual caused by the inhomogeneous surface distribution
of chemical elements. Among seven mapped elements, only Fe and Cr significantly
contribute to the amplitude of the observed light variability. In general, we
find a very good agreement between theory and observations. We confirm the
important role of Fe and Cr to the magnitude of the well-known depression
around 5200 \AA\ through the analysis of the peculiar $a$-parameter. Finally,
we show that the abundance spots of considered elements cannot explain the
observed variability in near UV and $\beta$ index which are likely due to some
other causes. The inhomogeneous surface distribution of chemical elements can
explain most of the observed light variability of the A-type CP star epsUMa.
