  We study the process of magnetic field annihilation and reconnection in
simulations of magnetised solar photosphere and chromosphere with magnetic
fields of opposite polarities and constant numerical resistivity. Exact
analytical solutions for reconnective annihilations are used to interpret the
features of magnetic reconnection in simulations of flux cancellation in the
solar atmosphere. We use MURaM high-resolution photospheric radiative
magneto-convection simulations to demonstrate the presence of magnetic field
reconnection consistent with the magnetic flux pile-up models. Also, a
simulated data-driven chromospheric magneto-hydrodynamic simulation is used to
demonstrate magnetic field and flow structures, which are similar to the ones
theoretically predicted. Both simulations demonstrate flow and magnetic field
structures roughly consistent with accelerated reconnection with magnetic flux
pile-up. The presence of standard Sweet-Parker type reconnection is also
demonstrated in stronger photospheric magnetic fields.
