The ice flux to the Lambert Glacier and Amery Ice Shelf along the Chinese inland traverse and implications for mass balance of the drainage basins, East Antarctica

AbstractWe combine European Remote-sensing Satellite (ERS-1) radar altimeter surface elevations (Fricker and others, 2000) with six different accumulation distributions to compute balance fluxes for the Lambert Glacier–Amery Ice Shelf drainage system. These interpolated balance fluxes are compared with fluxes derived from in situ measurements of ice thickness and velocity at 73 stations of the Lambert Glacier basin traverse and at 11 stations further downstream, to assess the system’s state of balance. For the upstream line we obtain a range of imbalance estimates, from −23.8% to +19.9% of the observed flux, reflecting the sensitivity to the accumulation distributions. For some of the accumulation distributions the imbalance estimates vary significantly between different parts of the line. Imbalance estimates for the downstream line range from −17.7% to +70.2%, with four of the estimates exceeding +30%, again reflecting the sensitivity of the result to input accumulation, and strongly suggesting that the mass balance of the region between the two lines is positive. Our results confirm the importance of accurate estimates of accumulation in ice-sheet mass-balance studies. Furthermore, they suggest that it is not possible to accurately determine the state of balance of large Antarctic drainage basins on the basis of currently available accumulation distributions.

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Ice thickness over the southern limit of the Amery Ice Shelf, East Antarctica, and reassessment of the mass balance of the central portion of the Lambert Glacier-Amery Ice Shelf system

Annals of Glaciology ◽

10.3189/2014aog66a154 ◽

2014 ◽

Vol 55 (66) ◽

pp. 81-86 ◽

Cited By ~ 3

Author(s):

Jiahong Wen ◽

Long Huang ◽

Weili Wang ◽

T.H. Jacka ◽

V. Damm ◽

...

Keyword(s):

Mass Balance ◽

Atmospheric Modeling ◽

East Antarctica ◽

Central Portion ◽

Ice Thickness ◽

Ice Shelf ◽

Southern Limit ◽

Surface Mass ◽

Amery Ice Shelf ◽

Lambert Glacier

AbstractWe combine radio-echo sounding ice thickness data from the BEDMAP Project database and the PCMEGA (Prince Charles Mountains Expedition of Germany and Australia) dataset to generate a new ice thickness grid for the southern limit region of the Amery Ice Shelf, East Antarctica. We then reassess the mass balance of the central portion of the Lambert-Amery system, incorporating flow information derived from synthetic aperture radar interferometry (InSAR) and a modeled surface mass-balance dataset based on regional atmospheric modeling. Our analysis reveals that Mellor and Fisher Glaciers are approximately in balance to the level of our measurement uncertainty, while Lambert Glacier has a positive imbalance of 4.2 ±2.3 Gta1. The mass budget for the whole Lambert Glacier basin is approximately in balance, and the average basal melt rate in the downstream section of the ice shelf is 5.1 ± 3.0 m a-1. Our results differ substantially from other recent estimates using hydrostatically derived ice thickness data.

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Revisiting Ice Flux and Mass Balance of the Lambert Glacier–Amery Ice Shelf System Using Multi-Remote-Sensing Datasets, East Antarctica

Remote Sensing ◽

10.3390/rs14020391 ◽

2022 ◽

Vol 14 (2) ◽

pp. 391

Author(s):

Derui Xu ◽

Xueyuan Tang ◽

Shuhu Yang ◽

Yun Zhang ◽

Lijuan Wang ◽

...

Keyword(s):

Remote Sensing ◽

Mass Balance ◽

Ice Sheet ◽

East Antarctica ◽

Ice Shelf ◽

Antarctic Ice Sheet ◽

Amery Ice Shelf ◽

Grounding Line ◽

Lambert Glacier ◽

The Antarctic

Due to rapid global warming, the relationship between the mass loss of the Antarctic ice sheet and rising sea levels are attracting widespread attention. The Lambert–Amery glacial system is the largest drainage system in East Antarctica, and its mass balance has an important influence on the stability of the Antarctic ice sheet. In this paper, the recent ice flux in the Lambert Glacier of the Lambert–Amery system was systematically analyzed based on recently updated remote sensing data. According to Landsat-8 ice velocity data from 2018 to April 2019 and the updated Bedmachine v2 ice thickness dataset in 2021, the contribution of ice flux approximately 140 km downstream from Dome A in the Lambert Glacier area to downstream from the glacier is 8.5 ± 1.9, and the ice flux in the middle of the convergence region is 18.9 ± 2.9. The ice mass input into the Amery ice shelf through the grounding line of the whole glacier is 19.9 ± 1.3. The ice flux output from the mainstream area of the grounding line is 19.3 ± 1.0. Using the annual SMB data of the regional atmospheric climate model (RACMO v2.3) as the quality input, the mass balance of the upper, middle, and lower reaches of the Lambert Glacier was analyzed. The results show that recent positive accumulation appears in the middle region of the glacier (about 74–78°S, 67–85°E) and the net accumulation of the whole glacier is 2.4 ± 3.5. Although the mass balance of the Lambert Glacier continues to show a positive accumulation, and the positive value in the region is decreasing compared with values obtained in early 2000.

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Modelling the response of the Lambert Glacier–Amery Ice Shelf system, East Antarctica, to uncertain climate forcing over the 21st and 22nd centuries

The Cryosphere ◽

10.5194/tc-8-1057-2014 ◽

2014 ◽

Vol 8 (3) ◽

pp. 1057-1068 ◽

Cited By ~ 20

Author(s):

Y. Gong ◽

S. L. Cornford ◽

A. J. Payne

Keyword(s):

Climate Model ◽

Global Environmental Change ◽

Ice Sheet ◽

Adaptive Mesh ◽

Ocean Model ◽

East Antarctica ◽

Ice Shelf ◽

Amery Ice Shelf ◽

Grounding Line ◽

Lambert Glacier

Abstract. The interaction between the climate system and the large polar ice sheet regions is a key process in global environmental change. We carried out dynamic ice simulations of one of the largest drainage systems in East Antarctica: the Lambert Glacier–Amery Ice Shelf system, with an adaptive mesh ice sheet model. The ice sheet model is driven by surface accumulation and basal melt rates computed by the FESOM (Finite-Element Sea-Ice Ocean Model) ocean model and the RACMO2 (Regional Atmospheric Climate Model) and LMDZ4 (Laboratoire de Météorologie Dynamique Zoom) atmosphere models. The change of ice thickness and velocity in the ice shelf is mainly influenced by the basal melt distribution, but, although the ice shelf thins in most of the simulations, there is little grounding line retreat. We find that the Lambert Glacier grounding line can retreat as much as 40 km if there is sufficient thinning of the ice shelf south of Clemence Massif, but the ocean model does not provide sufficiently high melt rates in that region. Overall, the increased accumulation computed by the atmosphere models outweighs ice stream acceleration so that the net contribution to sea level rise is negative.

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A precise monitoring of snow surface height in the region of Lambert Glacier basin-Amery Ice Shelf,�East Antarctica

Science in China Series D Earth Sciences ◽

10.1360/03yd0127 ◽

2005 ◽

Vol 48 (1) ◽

pp. 100 ◽

Cited By ~ 14

Author(s):

Cunde XIAO

Keyword(s):

East Antarctica ◽

Snow Surface ◽

Ice Shelf ◽

Amery Ice Shelf ◽

Lambert Glacier ◽

Lambert Glacier Basin

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Accumulation variability and mass budgets of the Lambert Glacier-Amery Ice Shelf system, East Antarctica, at high elevations

Annals of Glaciology ◽

10.3189/172756406781812249 ◽

2006 ◽

Vol 43 ◽

pp. 351-360 ◽

Cited By ~ 16

Author(s):

Jiahong Wen ◽

Kenneth C. Jezek ◽

Andrew J. Monaghan ◽

Bo Sun ◽

Jiawen Ren ◽

...

Keyword(s):

Spatial Variability ◽

Accumulation Rate ◽

Temporal Variations ◽

High Elevation ◽

East Antarctica ◽

Ice Shelf ◽

Surface Mass ◽

Amery Ice Shelf ◽

High Elevations ◽

Lambert Glacier

AbstractThe temporal and spatial variability of the annual accumulation rate and the mass budgets of five sub-basins of the Lambert Glacier-Amery Ice Shelf system (LAS), East Antarctica, at high elevations are assessed using a variety of datasets derived from field measurements and modeling. The annual temporal variations of the accumulation rate for four cores from the west and east sides of the LAS are around ±34%. Decadal fluctuation of the accumulation from the DT001 firn core drops to ±10%, and the 30 year fluctuation to ±5%, which is assumed to contain the information about the regional and long-term trend in accumulation. The 15-point running mean of the annual accumulation rate derived from stake measurements can remove most of the high-frequency spatial variation so as to better represent the local accumulation. Model simulations show that the spatial variability of erosion/ deposition of snow by the wind has a noticeable impact on the surface mass balance at the higher parts of the LAS. Mass-budget estimates at high-elevation sub-basins of the LAS suggest drainage 9 has a negative imbalance of −0.7 ± 0.4 Gta-1, Lambert and Mellor Glaciers have a positive imbalance of 3.9 ± 2.1 and 2.1 ±2.4 Gta-1 respectively, and Fisher Glacier and drainage 11 are approximately in balance. The higher-elevation region as a whole has a positive mass imbalance of 4.4 ± 6.3 Gta-1, which is consistent with the most recent radar altimetry assessment that shows an overall thickening over this region.

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The effects of ocean warming on melting and ocean circulation under the Amery Ice Shelf, East Antarctica

Annals of Glaciology ◽

10.3189/1998aog27-1-75-80 ◽

1998 ◽

Vol 27 ◽

pp. 75-80 ◽

Cited By ~ 25

Author(s):

M.J.M. Williams ◽

R. C. Warner ◽

W. F. Budd

Keyword(s):

Mass Balance ◽

Ocean Circulation ◽

Three Dimensional ◽

Ocean Model ◽

Ocean Warming ◽

East Antarctica ◽

Ice Shelf ◽

Temperature Changes ◽

Amery Ice Shelf ◽

Basal Melting

Using a three-dimensional ocean model specially adapted to the ocean cavity under the Amery Ice Shelf, we investigated the present ocean circulation and pattern of ice-shelf basal melting and freezing, the differences which would result from temperature changes in the seas adjacent to the Amery Ice Shelf, and the ramifications of these changes for the mass balance of the ice shelf. Under present conditions we estimate the net loss from the Amery Ice Shelf from excess basal melting over freezing at approximately 7.8 Gt a−1. This comprises a gross loss of 11.4 Gt a−1 at a mean rate of 0.42 m a−1, which is partially offset by freezing-on of 3.6 Gt a−1, at a mean rate of 0.19 m a−1. When the adjacent seas were assumed to warm by 1°C, we found the net melt increased to 31.6 Gt a−1, comprising 34.6 Gt a−1 of gross melt and 3.0 Gt a−1 of freezing.

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Surface meltstreams on the Amery Ice Shelf, East Antarctica

Annals of Glaciology ◽

10.3189/1998aog27-1-177-181 ◽

1998 ◽

Vol 27 ◽

pp. 177-181 ◽

Cited By ~ 33

Author(s):

Helen A. Phillips

Keyword(s):

Synthetic Aperture Radar Image ◽

East Antarctica ◽

Altimeter Data ◽

Topographic Map ◽

Ice Shelf ◽

Brightness Temperatures ◽

Amery Ice Shelf ◽

Microwave Imager ◽

Shelf Region ◽

Lambert Glacier

A topographic map of a 120 km by 20 km section of the Amery Ice Shelf, East Antarctica, mapped with the global positioning system (GPS) in the spring of 1995, revealed two long, shallow troughs in the ice-shelf surface. Smooth features coinciding with these troughs appeared in a synthetic aperture radar image acquired 18 months earlier. ERS-1 altimeter waveform sequences and backscatter measurements along repeat satellite ground tracks across the same section of the Amery Ice Shelf, for the 1993-94 summer, exhibited a dramatic change over a 2 km sector between 30 January and 2 February 1994. The change is consistent with the presence of liquid water on the ice-shelf surface, located in the deeper of the two troughs. A time series of special sensor microwave/ imager brightness temperatures over the Lambert Glacier-Amery Ice Shelf region for the same period has sharp maxima on 5 January and 21 January 1994. These maxima are interpreted as the melting events leading to the meltstream observed in the altimeter data 25 days later.

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Flow regime of the Lambert Glacier-Amery Ice Shelf system, Antarctica: structural evidence from Landsat imagery

Annals of Glaciology ◽

10.3189/1994aog20-1-401-406 ◽

1994 ◽

Vol 20 ◽

pp. 401-406 ◽

Cited By ~ 8

Author(s):

Michael J. Hambrey ◽

Julian A. Dowdeswell

Keyword(s):

Flow Regime ◽

Near Infrared ◽

Landsat Imagery ◽

Drainage Basins ◽

Ice Shelf ◽

Glacier System ◽

Amery Ice Shelf ◽

Conflicting Evidence ◽

Digital Manipulation ◽

Lambert Glacier

High-resolution visible and near-infrared satellite imagery provides a means of investigating the structural glaciology, and in turn the dynamics, of large ice masses. The Lambert Glacier-Amery Ice Shelf system is one of the largest ice drainage basins in Antarctica and has previously yielded conflicting evidence concerning its dynamic behaviour: either that the system has a propensity for surging or that it has a constant flow regime. Digital manipulation of Landsat imagery allows analysis of the structure of the glacier system, showing longitudinal foliation, medial moraines and crevasse patterns that provide no evidence of surging behavior during the residence time of ice in the glacier system.

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