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Mass Balance and Meteorological Conditions at Universidad Glacier, Central Chile
Published in Diego A. Rivera, Alex Godoy-Faundez, Mario Lillo-Saavedra, Andean Hydrology, 2018
Christophe Kinnard, Shelley MacDonell, Michal Petlicki, Carlos Mendoza Martinez, Jakob Abermann, Roberto Urrutia
Universidad Glacier (34°40’ S, 70°20’ W) is located above the commune of San Fernando in the O’Higgins Region of Chile, in the headwaters of the Tinguiririca River, itself a sub-catchment of the Rapel River basin (Fig. 5.15). It is part of the third glaciological zone that extends from 32-36° south (MOP-DGA, 2009). Morphologically speaking, it is a valley glacier that develops from the union of two contiguous sub-basins or cirques from which glacial tongues flow down, one toward the South and the other toward the West; both tongues coalesce together below icefalls. The main, lower glacier tongue displays ogives, with alternating bands of clear and debris-rich ice (Lliboutry, 1958) (Fig. 5.15). The glacier area in 2014 was 27.6 km2 and its linear length 10 km, from its front to the upper part of the western sub-basin. The glacier elevation ranges from 2450 m a.s.l. to a maximum of 4550 m a.s.l. in its northern sub-basin. The climate in the region is Mediterranean semi arid-temperate with annual precipitation around 700 mm a−1 (MOP-DGA, 2010). The area is located in a climatic transition zone: precipitation at high altitudes (above 2500 m a.s.l.) fluctuates between 500 mm a−1 in the northern semi-arid part of the region (32° S), to up to 2500 mm a−1 at 36° S (Pellicciotti et al., 2014). Interannual variability in precipitation is largely influenced by ENSO and the Pacific Decadal Oscillation (Garreaud, 2009; Garreaud et al., 2009). The 0°C isotherm altitude decreases in the same latitudinal range, from about 4000 m a.s.l. at 32° S to 3000 m a.s.l. at 36° S (Carrasco et al., 2005). According to previous studies carried out by the Glaciology Unit of the (DGA), Universidad Glacier lost an area of 1.99 km2 during the period 1945-2011, which amounts to an average of -0.03 km2 per year and a 6% total areal loss from the initial surface in 1945. The front retreated 1430 m during the same period, which amounts to -22 m per year on average. Universidad Glacier is the source of the San Andrés River, which changes its name downstream to Azufre River and drains into the Tinguiririca River, and eventually into Rapel River.
Erosional and depositional subglacial streamlining processes at Skálafellsjökull, Iceland: an analogue for a new bedform continuum model
Published in GFF, 2018
Jane K. Hart, Alexander I. Clayton, Kirk Martinez, Benjamin A. Robson
At Skálafellsjökull we had evidence for flutes, large flutes and drumlins within the foreland. By definition MSGL’s are large features, and extensive studies of their morphology, such as from Ely et al. (2016) are taken from Quaternary ice sheet sites (from satellite images) and the smallest 10th percentile are approximately 400 m long and 80 m wide. Bedforms of such large scale would be unlikely to form beneath valley glaciers and we suggest that the large flutes represented at Skálafellsjökull are a valley glacier/ smaller scale equivalent to MSGL. Given the bedform continuum model, we argue that MSGL’s are similarly formed by the same processes as flutes and drumlins (Hart 1997; Hindmarsh 1998b; King et al. 2009; Smith and Murray, 2009; Clarke 2010; Menzies et al. 2016, Stokes 2017).
Spatiotemporal variations in surface albedo during the ablation season and linkages with the annual mass balance on Muz Taw Glacier, Altai Mountains
Published in International Journal of Digital Earth, 2022
Xiaoying Yue, Zhongqin Li, Feiteng Wang, Jun Zhao, Huilin Li, Changbin Bai
The Muz Taw Glacier (47°04′N, 85°34′E), located in the interior of the Eurasian continent, is a typical valley glacier (Figure 1a and c). The glacier is exposed to the northeast, covers an area of 3.04 km2, and extends from an altitude of 3150 m above sea level (a.s.l.) to 3825 m a.s.l. (Figure 1b). Here, using a Landsat 8 image acquired in July 2015, the glacier outline was manually mapped, with the expected uncertainties of ±5% of the total glacier area for medium-resolution images (Paul et al. 2013). The glacier outline remained constant in subsequent studies.