A sensitivity study was performed in which the peak height of modeled FUV auroral emissions was displaced in altitude, an effect that can result from several causes in the modeling process. The purpose of the study was to examine the impact of such displacements on energy parameters extracted from FUV auroral observations. For this study, the N2 total ionization cross section was modified above 1 keV. Cross-sectional modifications are investigated for a variety of reasons including the fact that they can directly impact modeled emission height profiles and because different cross-section sets are adopted by different modelers. Though physically unrealistic, the magnitude of the change in cross section considered here is large enough that this study covers the expected range of uncertainties within a single model or between two or more different models. The values reported here can thus be viewed as upper limits for these uncertainties. The high-energy modifications result in changes of up to 3 km in the altitude of peak emission for FUV emissions excited by 10-keV electrons. For calculations using data from the Polar Ultraviolet Imager, derived energy flux and mean energy are changed by up to 16% and 23%, respectively, for 10-keV incident electrons. ¿ 2001 American Geophysical Union