Climate variability on millennial timescales has been observed in many geologic records covering the last glacial cycle. A potential source of this variability is the Laurentide ice sheet (LIS) in its periodic discharge of large quantities of icebergs to the North Atlantic. The present analysis considers whether regional variations in LIS topography could exert a significant influence on the atmosphere's stationary wave circulation. The maximum effect that regional changes in LIS topography have on the atmosphere's stationary wave circulation is determined using single-layer models of the atmosphere. Model experiments measure the individual contribution of 4.5¿¿7.5¿ sections of the LIS and Greenland topography to global mean stationary wave amplitude. Results show the possibility for a limited region of topography to control a disproportionate amount of the atmosphere's total response to topography. Moreover, the possibility exists for a reduction in topographic forcing to increase stationary wave amplitude. These results can be understood by considering how the mean flow controls the horizontal propagation of wave energy and superposition of wave amplitude. The location of regions with enhanced stationary wave sensitivity to topographic alteration is found to be sensitive to mean topographic height but not mean wind strength. The latter is found to primarily affect the overall amplitude of sensitivity rather than the pattern. The impact of two hypothetical changes in LIS topography is considered, and they are found to have widely different effects on the global stationary wave field. Stationary wave sensitivity to topography within the single-layer models suggests that variations in the size or shape of the LIS can be one factor important to climate variability on millennial timescales. ¿ 2000 American Geophysical Union