Changes in global climate and ocean temperatures have caused melting and subsequent thinning of the world’s ice sheets, as well as an increased rate of ice-mass loss to the oceans. Understanding the processes occurring beneath modern ice sheets is essential in determining how they are likely to respond to future climatic changes.
Calvin Shackleton uses glacial landforms in his PhD study to reconstruct past meltwater processes beneath the ice sheets that once covered the Barents Sea and Fennoscandia, and relies on computer-simulated ice sheets to recreate their meltwater drainage patterns. Ice flowing towards the ocean margins of ice sheets is controlled in part by the meltwater at their base, which fluctuates between high and low pressure with significant impacts on ice flow speed. Meltwater processes from a wide range of regions and time frames are studied, from drainage patterns spanning an entire glacial period, to more focused studies of meltwater and its impact on the dynamics of the ice sheet interior and margins.
Reconstructions of glacial landforms reveal iceberg creation amongst vast quantities of meltwater at a retreating ice margin to the south of Svalbard. In the central Barents Sea, other reconstructions show highly dynamic drainage systems that operated throughout the growth and decay of the former ice sheet. Meltwater drainage modelling over the entire region predicts potential locations for water storage within subglacial lakes, while reconstructing vast drainage systems beneath past ice sheets, providing insights into the potential drainage configurations beneath present-day Antarctica and Greenland.
Shackleton defended his thesis on June 11th, 2019 at the Department of Geosciences, UiT The Arctic University of Norway. His PhD was funded by the Centre for Arctic Gas Hydrate, Environment, and Climate (CAGE).