Seasonal evolution of supraglacial lake volume from ASTER imagery

Abstract

Water stored in and released from supraglacial lakes is an important factor when considering the seasonal and long-term evolution of the Greenland ice sheet. Here we use a radiative transfer model to estimate changes in the depth and volume of a supraglacial lake on the surface of Jakobshavn Isbræ, West Greenland, between 2002 and 2005. When compared to estimates of the lake depth determined from airborne lidar observations, we estimate that the root-mean-square departure of the modelled lake depths was 0.3 m during cloud-free conditions. The maximum lake area, depth and volume were 3.4 km2, 9.6 ±1.0 m and (18.6±3.7)×106 m3, respectively. When sequenced according to the number of positive degree-days (PDDs) accumulated prior to each image, we observe that the lake volume evolves in three distinct phases. At the start of the melting season, the rate of filling is slow; after approximately 80 PDDs the rate of filling increases by a factor ∽3, and after approximately 125 PDDs the lake drains rapidly. We estimate that the lake drains at a minimum rate of (2.66±0.53)×106 m3 d–1 over a 6 day period.

Meltwater chemistry and solute export from a Greenland Ice Sheet catchment, Watson River, West Greenland

“…Sugden et al, 1985;Russell et al, 1990Russell et al, , 1995Russell et al, , 2011Mernild and Hasholt, 2009;Carrivick et al, 2013). On the western part of the GrIS, supraglacial lakes store and release considerable volumes of meltwater (Georgiou et al, 2009), but a direct link between rapid release of supraglacial lake water and discharge in Watson River has not yet been shown.…”

Toward Monitoring Surface and Subsurface Lakes on the Greenland Ice Sheet Using Sentinel-1 SAR and Landsat-8 OLI Imagery

“…Previous remote sensing studies in the area have quantified supraglacial lake area and volume (e.g., Box and Ski, 2007;Georgiou et al, 2009;Williamson et al, 2017) and found that lakes have been forming and draining at higher elevations as melt rates have increased in recent years (Selmes et al, 2011;Howat et al, 2013;Fitzpatrick et al, 2014;Pope et al, 2016), particularly in very warm years, when lakes also drain earlier (Liang et al, 2012). The study region was chosen to match the total extent of the selected Landsat-8 scenes (paths 006, 007, 008, 009, and 010, and rows 011 and 012; Figure 1).…”

A decade (2002–2012) of supraglacial lake volume estimates across Russell Glacier, West Greenland

“…Previous studies on SGLs have quantified spatial and temporal variations in SGL area across different sectors of the GrIS (e.g. Georgiou et al, 2009;Sundal et al, 2009;Selmes et al, 2011;Liang et al, 2012), and have estimated their volume (e.g. Box and Ski, 2007;Sneed and Hamilton, 2007), whilst others have attempted to model SGL evolution (e.g.…”