  The phenomenological Disc Instability Model has been successful in
reproducing the observed light curves of dwarf nova outbursts by invoking an
enhanced Shakura-Sunyaev $\alpha$ parameter $\sim0.1-0.2$ in outburst compared
to a low value $\sim0.01$ in quiescence. Recent thermodynamically consistent
simulations of magnetorotational (MRI) turbulence with appropriate opacities
and equation of state for dwarf nova accretion discs have found that thermal
convection enhances $\alpha$ in discs in outburst, but only near the hydrogen
ionization transition. At higher temperatures, convection no longer exists and
$\alpha$ returns to the low value comparable to that in quiescence. In order to
check whether this enhancement near the hydrogen ionization transition is
sufficient to reproduce observed light curves, we incorporate this MRI-based
variation in $\alpha$ into the Disc Instability Model, as well as
simulation-based models of turbulent dissipation and convective transport.
These MRI-based models can successfully reproduce observed outburst and
quiescence durations, as well as outburst amplitudes, albeit with different
parameters from the standard Disc Instability Models. The MRI-based model
lightcurves exhibit reflares in the decay from outburst, which are not
generally observed in dwarf novae. However, we highlight the problematic
aspects of the quiescence physics in the Disc Instability Model and MRI
simulations that are responsible for this behavior.
