Title

Long-term Shifts in Feedbacks Among Glacier Surface Change, Melt Generation and Runoff, McMurdo Dry Valleys, Antarctica

Published In

Hydrological Processes

Document Type

Citation

Publication Date

8-2021

Abstract

Glaciers of the McMurdo dry valleys (MDVs) Antarctica are the main source of streamflow in this polar desert. Because summer air temperatures hover near 0°C small changes in the energy balance strongly affect meltwater generation. Here we demonstrate that increased surface roughness, which alters the turbulent transfer of energy between the ice surface and atmosphere, yields a detectable increase in meltwater runoff. At low elevations on the glaciers, basin-like topography became significantly rougher over 13 years between repeat lidar surveys, yielding greater melt. In contrast, the smoother ice at higher elevation exhibited no detectable change in roughness. We pose a conceptual model of the cycle of glacier surface change as a result of climate forcing whereby glacier surfaces transition from being dominated by sublimation to becoming increasingly melt-dominated, which is reversible under prolonged cool periods. This research advances our understanding of warm season effects on polar glaciers.

Description

Available on August 20, 2022

Locate the Document

https://doi.org/10.1002/hyp.14292

DOI

10.1002/hyp.14292

Persistent Identifier

https://archives.pdx.edu/ds/psu/37131

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