Surface velocity and ice discharge of the ice cap on King George Island, Antarctica

Abstract

ABSTRACT. Glaciers on King George

Bedload transport in two creeks at the ice-free area of the Baranowski Glacier, King George Island, West Antarctica

“…A similar situation is associated with the mass balance of the glaciers. From January 2008 to January 2011, mass loss was -0.64 ± 0.38 m w.e.a -1 , for the entire ice cap (Osmanoğlu et al 2013). Recently, negative mass balance was also confirmed by Rückamp et al (2010) and Simões et al (2015).…”

Recent Deceleration of the Ice Elevation Change of Ecology Glacier (King George Island, Antarctica)

“…The ice elevation change rate for the common ablation area over all analyzed periods (1979-2001-2012-2016 Ice surface lowering of Ecology Glacier has significantly decelerated in the beginning of the 21st century, especially in 2012-2016 when the glacier was close to equilibrium. Ice flow velocities of the terminal part of Ecology Glacier have been very low at least since 1995 [27,63]. Therefore, we do not expect large variation in ice flux due to termini retreat and the latter should be driven mainly by an enhanced calving when the front retreats to deeper water in the proglacial lagoon.…”

“…The Warszawa Icefield shows generally low dynamics comparing to other parts of the King George Island and is not contributing significantly to the overall mass balance of the entire ice cap of King George Island [27]. Therefore it is more sensitive to the surface mass balance changes than to ice flow variations, showing a more direct response to climate signals than the more dynamic neighbouring icefields.…”

“…A major part of the island is covered by an ice cap divided into five main ice basins: three connected domes along the main ridge (A-Bellingshausen, B-Arctowski and C-unnamed), and Kraków and Warszawa Icefields on the southern peninsulas [25]. Despite there being a number of published glacial extent change studies (e.g., [25][26][27][28][29]), only a few studies of glacier volume change in the South Shetland Islands area have been conducted (e.g., [20,26,30]). The majority of ice volume change studies covering this region are still based on volume-area scaling (e.g., [22,31]), with little in situ data that could provide robust validation.…”

A 14-year dataset of in situ glacier surface velocities for a tidewater and a land-terminating glacier in Livingston Island, Antarctica

“…These islands, located off the north-western tip of the Antarctic Peninsula, previously had a scarce record of in situ velocity observations, which included measurements in the late 1980s on Nelson Island (Ren Jiaven et al, 1995), earlier measurements in the late 1990s on Johnsons Glacier (Ximenis et al, 1999), and measurements in the Arctowski Icefield, the Bellingshausen Dome, and the Central Dome of King George Island between 1999and 2008/09 (Blindow et al, 2010Rückamp et al, 2010Rückamp et al, , 2011. Such in situ velocity measurements are critical for the validation of the estimates of remote-sensor-based studies of ice discharge in the region such as those by Osmanoglu et al (2013Osmanoglu et al ( , 2014 for King George and Livingston islands (the present dataset has in fact been used in the latter paper with such purposes), as well as for tuning free parameters of glacier dynamics models, as done by Martín et al (2004) and Otero et al (2010) using an earlier (and shorter) version of the dataset presented. An added interest of the presented velocity record is that it corresponds to both a tidewater glacier and a landterminating glacier, two glacier types that are typical in this region but very different in dynamical behaviour.…”