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Detailed measurements of the photochemical and photophysical properties of an adsorbate on discontinuous metal-island films are used to explore the unusual electrodynamics near rough metal surfaces. Several aspects of the properties have been measured: the magnitude the temporal decay of the fluorescence, the shape and temporal evolution of the fluorescence spectrum, and the effects on the spectrum of a photochemical hole-burning process. Dramatic increases in the fluorescent decay rate and decreases in the photochemical reaction rate as well as systematic spectral shifts of the emission of molecules experiencing the different electrodynamic environments on the island film are observed. These results reveal the strong effects of the coupling between the adsorbate and the plasma resonances localized on the islands of the film. We model our results using the electrodynamic picture which has successfully described many aspects of surface-enhanced Raman scattering and other optical processes on island films. The excellent agreement between this model and our results suggests that an important feature of the electrodynamics at these rough metal surfaces is the dipolar character of the couplings between the surface, the adsorbate, and the optical fields.