Supplementary material to "Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula"

AbstractFollowing the collapse of Larsen A in 1995, about 3200 km2 of Larsen B ice shelf disintegrated in early 2002 during the warmest summer recorded on the northeastern Antarctic Peninsula. Immediately prior to disintegration the last field campaign was carried out on Larsen B. Measurements included surface net mass balance, velocity and strain rate on a longitudinal transect along Crane Glacier flowline and over a remnant section confined within Seal Nunataks that survived the collapse. In addition, an automatic weather station located nearby allowed derivation of melt days relevant to the formation and extent of surface meltwater. Repeated surveys allowed us to detect a significant acceleration in ice-flow velocity and associated increasing strain rates along the longitudinal transect. It may be possible to use this acceleration as a predictor of imminent ice-shelf collapse, applicable to ice shelves subject to similar climatic conditions. Additional information on recent ongoing changes was provided by a visible satellite image acquired in early 2003.

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2001–2009 elevation and mass losses in the Larsen A and B embayments, Antarctic Peninsula

Journal of Glaciology ◽

10.3189/002214311797409811 ◽

2011 ◽

Vol 57 (204) ◽

pp. 737-754 ◽

Cited By ~ 46

Author(s):

Christopher A. Shuman ◽

Etienne Berthier ◽

Ted A. Scambos

Keyword(s):

Antarctic Peninsula ◽

Loss Rate ◽

Ice Shelf ◽

Laser Altimetry ◽

Ice Shelves ◽

Ice Volume ◽

Mass Losses ◽

Digital Elevation ◽

Modis Imagery ◽

Elevation Changes

AbstractWe investigate the elevation and mass-balance response of tributary glaciers following the loss of the Larsen A and B ice shelves, Antarctic Peninsula (in 1995 and 2002 respectively). Our study uses MODIS imagery to track ice extent, and ASTER and SPOT5 digital elevation models (DEMs) plus ATM and ICESat laser altimetry to track elevation changes, spanning the period 2001–09. The measured Larsen B tributary glaciers (Hektoria, Green, Evans, Punchbowl, Jorum and Crane) lost up to 160 m in elevation during 2001–06, and thinning continued into 2009. Elevation changes were small for the more southerly Flask and Leppard Glaciers, which are still constrained by a Larsen B ice shelf remnant. In the northern embayment, continued thinning of >3 m a−1 on Drygalski Glacier, 14 years after the Larsen A ice shelf disintegrated, suggests that mass losses for the exposed Larsen B tributaries will continue for years into the future. Grounded ice volume losses exceed 13 km3 for Crane Glacier and 30 km3 for the Hektoria–Green–Evans glaciers. The combined mean loss rate for 2001–06 is at least 11.2 Gt a−1. Our values differ significantly from published mass-budget-based estimates for these embayments, but are a reasonable fraction of GRACE-derived rates for the region (∼40 Gt a−1).

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Detailed ice loss pattern in the northern Antarctic Peninsula: widespread decline driven by ice front retreats

The Cryosphere ◽

10.5194/tc-8-2135-2014 ◽

2014 ◽

Vol 8 (6) ◽

pp. 2135-2145 ◽

Cited By ~ 40

Author(s):

T. A. Scambos ◽

E. Berthier ◽

T. Haran ◽

C. A. Shuman ◽

A. J. Cook ◽

...

Keyword(s):

Mass Loss ◽

Antarctic Peninsula ◽

Snow Accumulation ◽

Stereo Image ◽

Western Coast ◽

Elevation Change ◽

Ice Shelf ◽

Laser Altimetry ◽

Ice Volume ◽

Basin Scale

Abstract. The northern Antarctic Peninsula (nAP, < 66° S) is one of the most rapidly changing glaciated regions on earth, yet the spatial patterns of its ice mass loss at the glacier basin scale have to date been poorly documented. We use satellite laser altimetry and satellite stereo-image topography spanning 2001–2010, but primarily 2003–2008, to map ice elevation change and infer mass changes for 33 glacier basins covering the mainland and most large islands in the nAP. Rates of ice volume and ice mass change are 27.7± 8.6 km3 a−1 and 24.9± 7.8 Gt a−1, equal to −0.73 m a−1 w.e. for the study area. Mass loss is the highest for eastern glaciers affected by major ice shelf collapses in 1995 and 2002, where twelve glaciers account for 60% of the total imbalance. However, losses at smaller rates occur throughout the nAP, at both high and low elevation, despite increased snow accumulation along the western coast and ridge crest. We interpret the widespread mass loss to be driven by decades of ice front retreats on both sides of the nAP, and extended throughout the ice sheet due to the propagation of kinematic waves triggered at the fronts into the interior.

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Recent ice-surface-elevation changes of Fleming Glacier in response to the removal of the Wordie Ice Shelf, Antarctic Peninsula

Annals of Glaciology ◽

10.3189/172756410791392727 ◽

2010 ◽

Vol 51 (55) ◽

pp. 97-102 ◽

Cited By ~ 15

Author(s):

J. Wendt ◽

A. Rivera ◽

A. Wendt ◽

F. Bown ◽

R. Zamora ◽

...

Keyword(s):

Antarctic Peninsula ◽

Regional Climate ◽

Airborne Lidar ◽

Similar Data ◽

Ice Shelf ◽

International Polar Year ◽

Ice Flow ◽

Ice Shelves ◽

Elevation Changes ◽

The Antarctic

AbstractRegional climate warming has caused several ice shelves on the Antarctic Peninsula to retreat and ultimately collapse during recent decades. Glaciers flowing into these retreating ice shelves have responded with accelerating ice flow and thinning. The Wordie Ice Shelf on the west coast of the Antarctic Peninsula was reported to have undergone a major areal reduction before 1989. Since then, this ice shelf has continued to retreat and now very little floating ice remains. Little information is currently available regarding the dynamic response of the glaciers feeding the Wordie Ice Shelf, but we describe a Chilean International Polar Year project, initiated in 2007, targeted at studying the glacier dynamics in this area and their relationship to local meteorological conditions. Various data were collected during field campaigns to Fleming Glacier in the austral summers of 2007/08 and 2008/09. In situ measurements of ice-flow velocity first made in 1974 were repeated and these confirm satellite-based assessments that velocity on the glacier has increased by 40–50% since 1974. Airborne lidar data collected in December 2008 can be compared with similar data collected in 2004 in collaboration with NASA and the Chilean Navy. This comparison indicates continued thinning of the glacier, with increasing rates of thinning downstream, with a mean of 4.1 ± 0.2 m a−1 at the grounding line of the glacier. These comparisons give little indication that the glacier is achieving a new equilibrium.

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