Greenland Subglacial Hydrology Model

• Main Author: Oswalt, Meghan K.
• Format: Other/Unknown Material
• Language: unknown
• Published: University of Montana 2014
• Subjects: Greenland; basal water height; sliding; subglacial; hydraulic potential; Ice Sheet
• Online Access: https://scholarworks.umt.edu/etd/4287; https://scholarworks.umt.edu/context/etd/article/5310/viewcontent/Oswalt_Meghan_Thesis.pdf

Ice sheet models are used to predict ice sheet retreat and sea level rise. As our climate changes,the need for these predictions becomes more critical. Current research supports a relationship between basal sliding speed and surface melt availability, which varies spatially and temporally. The nature of this relationship is restricted by a lack of understanding of the characteristics of subglacial hydrology, such as the structure and storage capacity of the system. The ability to accurately predict basal sliding and subsequent calving along outlet glaciers requires an improved understanding of subglacial drainage. Subglacial hydrology models for ice sheets are used to predict water pressure and prescribe a drainage system in the absence of direct observation. These models employ a non-linear partial differential equation to describe the physics of the system. Using the finite element package FeNICs, we apply a subglacial hydrology model to the Greenland ice sheet. Initial results from our model provide reasonable average basal water height and hydraulic potential fields, but demonstrate a lack of sensitivity to non-measured parameters. Further work is needed to improve model convergence and support the development of an adjoint model to improve non-measured parameter estimates.