Preprints
https://doi.org/10.5194/tc-2020-366
https://doi.org/10.5194/tc-2020-366

  18 Jan 2021

18 Jan 2021

Review status: this preprint is currently under review for the journal TC.

Topography exerts primary control on the rate of Gulf of Alaska ice-marginal lake area change over the Landsat record

Hannah R. Field1,2, William H. Armstrong1, and Matthias Huss3,4,5 Hannah R. Field et al.
  • 1Department of Geological and Environmental Sciences, Appalachian State University, Boone, NC 28607, USA
  • 2School of Earth Sciences, The Ohio State University, Columbus, OH 43210, USA
  • 3Laboratory of Hydraulics, Hydrology and Glaciology (VAW), ETH Zurich, Zurich, 8093, Switzerland
  • 4Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
  • 5Department of Geosciences, University of Fribourg, Fribourg, Switzerland

Abstract. Lakes in contact with glacier margins can impact glacier evolution as well as the downstream biophysical systems, flood hazard, and water resources. Recent work indicates that glacier wastage influences ice-marginal lake evolution, although precise physical controls are not well understood. Here, we quantify ice-marginal lake area change in understudied northwestern North America from 1984–2018 and investigate climatic, topographic, and glaciological influences on lake area change. We delineate timeseries of sampled lake (n = 107) perimeters and find that regional lake area has increased 58 % in aggregate, with individual proglacial lakes growing by 3.08 km2 and ice-dammed lakes shrinking by 0.88 km2 on average. A statistical investigation of climate reanalysis data suggests that changes in summer temperature and winter precipitation exert minimal direct influence on lake area change. Utilizing existing datasets of observed and modelled glacial characteristics, we find that large, wide glaciers with thick lake-adjacent ice are associated with the fastest rate of lake area change, particularly where they are undergoing rapid mass loss in recent times. We observe a dichotomy in which large, low-elevation coastal proglacial lakes have changed most in absolute terms, while small, interior lakes at high elevation changed most in relative terms. These systems have not experienced the most dramatic temperature or precipitation change, nor are they associated with the highest rates of glacier mass loss. Our work suggests that, while climatic and glaciological factors must play some role in determining lake area change, the influence of a lake's specific geometry and topographic setting overrides these external controls.

Hannah R. Field et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Review of Field et al. ‘Topography exerts primary control on the rate of Gulf of Alaska ice-marginal lake area change over the Landsat record’.', Jenna Sutherland, 05 Feb 2021
  • RC2: 'Comment on tc-2020-366', Anonymous Referee #2, 15 Feb 2021

Hannah R. Field et al.

Hannah R. Field et al.

Viewed

Total article views: 393 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
286 96 11 393 22 5 4
  • HTML: 286
  • PDF: 96
  • XML: 11
  • Total: 393
  • Supplement: 22
  • BibTeX: 5
  • EndNote: 4
Views and downloads (calculated since 18 Jan 2021)
Cumulative views and downloads (calculated since 18 Jan 2021)

Viewed (geographical distribution)

Total article views: 368 (including HTML, PDF, and XML) Thereof 368 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 19 Apr 2021
Download
Short summary
The growth of a glacier lake alters the hydrology, ecology, and glaciology of its surrounding region. We investigate modern glacier lake area change across northwestern North America using repeat satellite imagery. Broadly, we find that lakes downstream from glaciers grew, while lakes dammed by glaciers shrunk. Our results suggest that the shape of the landscape surrounding a glacier lake plays a larger role in determining how quickly a lake changes than climatic or glaciologic factors.