  We produce a 10-day series of simulated Doppler images at a 15-minute cadence
that reproduces the spatial and temporal characteristics seen in the SOHO/MDI
Doppler data. Our simulated data contains a spectrum of cellular flows with but
two necessary components --- a granule component that peaks at wavenumbers of
about 4000 and a supergranule component that peaks at wavenumbers of about 110.
We include the advection of these cellular components by a differential
rotation profile that depends on latitude and wavenumber (depth). We further
mimic the evolution of the cellular pattern by introducing random variations to
the amplitudes and phases of the spectral components at rates that reproduce
the level of cross-correlation as a function of time and latitude. Our
simulated data do not include any wave-like characteristics for the
supergranules yet can accurately reproduce the rotation characteristics
previously attributed to wave-like characteristics.
