The aerial photo uncertainty is associated with digitizing the HWL shoreline
an aerial photograph while the shoreline proxy offset is due to
uncertainty in HWL shorelines due to variations in water level
(Table 1). The inaccuracy of ±3 m associated with the GPS receiver
was within the error margin estimated by Hapke et al. (2010),
hence, Hapke et al. (2010)’s error estimate of ±4.5 mwas applied to
the 2012 shoreline.