RECONSTRUCTION OF KOETTLITZ GLACIER IN THE MCMURDO SOUND REGION, ANTARCTICA DURING THE LAST GLACIAL MAXIMUM AND TERMINATION

The warming trend of the 20^th century has caused significant environmental changes to the cryosphere in the polar regions. Because the Antarctic Ice Sheet plays such an important role in the global climate system, it is necessary to understand how it has responded to variations in climate in the past in order to predict how it will react to warming in the future. This project will reconstruct the behavior of grounded ice in the McMurdo Sound region where it interacted with marine-terminating local glaciers at the end of the last glacial period.

The particular focus of this project is Koettlitz Glacier, a local glacier that flows from the Royal Society Range into McMurdo Sound. There are currently two competing hypotheses as to how this glacier behaved during the last glacial period. The first is that it, along with other East Antarctic glaciers expanded to fill the western Ross Sea Embayment. The second is that the embayment was filled largely by grounded marine ice with origins farther south in the Transantarctic Mountains and West Antarctica. We will reconstruct the past extent and behavior of Koettlitz Glacier from geomorphological mapping and high-resolution dating from Beryllium-10 surface-exposure ages and Carbon-14 dates of algae within glacial moraines and shorelines of former ice-dammed ponds. Understanding how the ice sheet responded to Termination I, the last period of rapid warming in Earth’s history, could provide clues to how it might respond to the current and future periods of warming.