| Summary: | In this thesis, I have used remote sensing and modeling techniques to investigate Antarctic ice shelf surface hydrology with the purpose of answering three key questions: 1) How do surface drainage systems evolve over a typical summertime melt season, over several consecutive melt seasons, and over several decades? 2) What controls the expansion of surface hydrology networks? and 3) Will surface drainage expand into areas vulnerable to hydrofracture and important for buttressing when meltwater volume increases in a warmer, future climate? In Chapter 1, our analysis of satellite observations of Amery Ice Shelf’s surface drainage networks suggests that their downstream extent varies inter-annually, that this variability is not simply the result of inter-annually variability in melt rates, and that ice-shelf topography plays a crucial role. Consecutive years of extensive melting lead to year-on-year expansion of the drainage system, potentially through a link between melt production, refreezing in firn, and the maximum extent of the lakes at the downstream termini of drainage. These mechanisms are important when evaluating the potential of drainage systems to grow in response to increased melting, delivering meltwater to areas of ice shelves vulnerable to hydrofracture. In Chapter 2, we use high resolution elevation data to delineate hydrologic catchments on Amery, Roi Baudouin, Larsen C, Nivlisen, and Riiser-Larsen Ice Shelves. We compare our results spatially with modelled present-day melt production, future melt predictions, and stress-based vulnerability to hydrofracture, to examine the controls on these hydrologically important characteristics of the topography. The high volume elevation data present computational challenges that cannot be overcome with traditional data analysis workflows. Therefore, pre-processing for catchment delineation is made possible by parallelizing these tasks with the computational power of cloud-based cluster computing. Catchments with high basin volumes are found clustered near ...
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