Surveillance systems, especially for mid-course detection missions, must acquire and track targets against a naturally structured earthlimb and aurora background. The background levels are highly variable both in wavelength and radiance. "Standard" one-dimensional line-of-sight models for describing such backgrounds have been developed by organizations such as the Geophysics Laboratory, Naval Research Laboratory and Defense Nuclear Agency. As part of the newly established SDI/NRL Strategic Scene Generator Model effort, we have developed techniques for applying these background models to represent multi- dimensional earthlimb and aurora background scene realizations. We present these model techniques and sample scene results for both earthlimb and auroral phenomenology. Naturally occurring statistical structure for both earthlimb and aurora modelling is described as it effects clutter representation in the scenes. Specific systems-oriented scene realizations are illustrated.