Debris properties and mass-balance impacts on adjacent debris-covered glaciers, Mount Rainier, USA

• Published in: Arctic, antarctic, and alpine research Vol. 51; no. 1; pp. 70 - 83
• Main Authors: Moore, Peter L., Nelson, Leah I., Groth, Theresa M. D.
• Format: Journal Article
• Language: English
• Published: Boulder Taylor & Francis 01.01.2019; Taylor & Francis Ltd; Taylor & Francis Group
• Subjects: Carbon; Climate change; Debris; Debris-covered glacier; Detritus; Energy balance; Glacial drift; glacier; Glacier retreat; Glaciers; Landsat; Landsat satellites; mass balance; Mass balance of glaciers; Mount Rainier; Remote sensing; Surface temperature; Thermal properties; Thermal resistance; Thermodynamic properties; United States > US; Mount Rainier
• ISSN: 1523-0430; 1938-4246
• DOI: 10.1080/15230430.2019.1582269

The north and east slopes of Mount Rainier, Washington, are host to three of the largest glaciers in the contiguous United States: Carbon Glacier, Winthrop Glacier, and Emmons Glacier. Each has an extensive blanket of supraglacial debris on its terminus, but recent work indicates that each has responded to late twentieth- and early twenty-first-century climate changes in a different way. While Carbon Glacier has thinned and retreated since 1970, Winthrop Glacier has remained steady and Emmons Glacier has thickened and advanced. There are several possible climatic and dynamic factors that can account for some of these disparities, but differences in supraglacial debris properties and distribution have not been systematically evaluated. We combine field measurements and satellite remote sensing analysis from a 10-day period in the 2014 melt season to estimate both the debris thickness distribution and key debris thermal properties on Emmons Glacier. A simplified energy-balance model was then used with debris surface temperatures derived from Landsat 8 thermal infrared bands to estimate the distribution of debris across all three debris-covered termini. The results suggest that differences in summer balance among these glaciers can be partly explained by differences in the thermal resistance of their debris mantles.