Persistent Wind Scour in Antarctica

I completed my thesis at Amherst College with Dr. Nicholas Holschuh, where I graduated with cum laude honors. My entire thesis is available to read online and you can read the abstract below.

Dome A is a potential candidate for holding some of the oldest ice on the planet. Ice in the region may contain a climate record of atmospheric gas concentrations that can inform our understanding of the Mid-Pleistocene Transition (MPT), during which glacial cycles changed periodicity. But Dome A also has regions of persistent wind scour, which can disrupt the climate record. Unconformities identified in englacial layering using ice-penetrating radar provide information about the persistence of wind scour at Dome A, East Antarctica. These features are formed when high wind speeds drive net sublimation and snow transport at the ice surface. The location of these unconformities varies with the surface climate, and their geometry varies with the snow accumulation rate and ice flow speed. This project uses remote sensing techniques to evaluate the spatial distribution of wind scour at Dome A, and use the unconformities to determine the persistence of wind scouring events.

I show that individual variables, described as predictive of wind scour in the existing glaciological literature, do not correlate with identified wind scour in the stratigraphy at Dome A. A lack of correlation between scour zones and unconformity presence despite a larger sample size of unconformities and a lower prediction threshold than previously established does not correctly predict the presence of over 50% of the unconformities. This suggests that modern climate variables and remote sensing data alone are not accurate predictors of wind scour. Additionally, the maximum age bounds I established on my unconformities suggest that wind scour was likely prevalent up to 161 ka, and the ice below the unconformities is likely undisturbed, suggesting that there is old ice at Dome A that contains at least a semi-continuous climate record. This thesis provides a framework for understanding wind scour processes and their persistent effect on the climate record held at Dome A, thus providing insight into Dome A’s ability to hold a climate record that can inform our understanding of past and future climate change.