UC Irvine

The modern contribution of glaciers and ice sheets to sea level rise increases with time and has largely been attributed to anthropogenic sources. The mass losses through the dynamic discharge of ice into the ocean has played a major role in the last two decades with a widespread acceleration of marine terminating glaciers. Recent studies have shown that these changes are closely linked to the ocean conditions, the bedrock and fjord topography. It is therefore crucial to document in details the evolution of glaciers and ice sheets, the bedrock topography and ocean properties to understand how and why the glaciers have been changing recently. Therefore, the aim of this thesis is to improve our understanding of ice dynamics and ice-ocean interaction by using a set of satellite and airborne remote sensing data over key regions. We describe the evolution of glacier dynamics and the detailed partitioning of the mass losses of the Queen Elizabeth Islands, Canada since the 1990s, which are major contributors to recent sea level rise. In Antarctica, we provide the first map of the sub-ice shelf bathymetry of the largest glaciers in the Amundsen Sea Embayment that reveals deep pathways for circumpolar warm water up to the grounding line of the glaciers. Finally, we assembled a comprehensive map of the bedrock and fjord topography of the southeastern coast of Greenland, and interpret the pattern of glacier retreat during the last 80 years, which was not possible before. The work proposed help to understand the recent deglaciation history of key regions in the Arctic, Greenland and Antarctica. The new mapping of sub-ice shelf, bedrock and fjord topography provides invaluable insights for mass balance calculation, ocean and ice-sheet modeling.