Rapid glacier retreat rates observed in West Antarctica

Glacier variations 1930–1970, 1970–1995, 1995–2017 and 2017–2018 The Icelandic Glaciological Society received reports on 46 measurements sites of glacier front variations in the autumn of 2018. Glacier retreat was observed at 33 survey sites whereas advances where reported from 5 sites, and 4 showed no signs of change. Snow covered glacier margins, bad weather or floating icebergs in the proglacial lakes prevented measurement at a few sites. One new site was added to the network, the western part of Þórisjökull.

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Central West Antarctica aeromagnetic data; a web site for distribution of data and maps (paper edition)

Open-File Report ◽

10.3133/ofr99420 ◽

1999 ◽

Cited By ~ 6

Author(s):

R.E. Sweeney ◽

C.A. Finn ◽

D.D. Blankenship ◽

R.E. Bell ◽

John C. Behrendt

Keyword(s):

Web Site ◽

Aeromagnetic Data ◽

West Antarctica ◽

Paper Edition

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Discussion and reply: Marie Byrd Land, West Antarctica: Evolution of Gondwana's Pacific margin constrained by zircon U-Pb geochronology and feldspar common-Pb isotopic compositions Discussion

Geological Society of America Bulletin ◽

10.1130/0016-7606(2002)114<1178:darmbl>2.0.co;2 ◽

2002 ◽

Vol 114 (9) ◽

pp. 1178-1180

Author(s):

R.J. Pankhurst

Keyword(s):

West Antarctica ◽

Isotopic Compositions ◽

Pacific Margin

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A VARIED SUBGLACIAL LANDSCAPE UNDER THWAITES GLACIER, WEST ANTARCTICA

10.1130/abs/2017am-302865 ◽

2017 ◽

Author(s):

Knut Christianson ◽

◽

Nicholas D. Holschuh ◽

John Paden ◽

Jordan Sprick ◽

...

Keyword(s):

West Antarctica

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A Lacustrine Glacier Retreat Sequence from the Permo-Carboniferous Dwyka Formation, Republic of South Africa

Journal of Glaciology ◽

10.1017/s0022143000030446 ◽

1983 ◽

Vol 29 (103) ◽

pp. 515-520

Author(s):

J. N. J. Visser

Keyword(s):

South Africa ◽

Lacustrine Sediments ◽

Glacier Retreat ◽

Marine Transgression ◽

Northern Margin ◽

Valley Fill ◽

Karoo Basin ◽

Ice Retreat ◽

Glacier Advance

Abstract The upper part of a Permo-Carboniferous glacial valley fill along the northern margin of the Karoo Basin includes glacio-lacustrine sediments. During the last glacier advance into the lake, a bedded heterogeneous diamictite facies was deposited and, on glacier retreat, a sequence of deformed siltstones with diamictite lenses and sandstone beds, varved shale and rhythmite shale was laid down. Black carbonaceous mud was deposited during the subsequent marine transgression. According to varve counts, the glacier receded from the valley over a period of 500 to 1 000 years and it is concluded that the overall ice-retreat rate during the Permo-Carboniferous deglaciation was relatively high.

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Shift in polar benthic community structure in a fast retreating glacial area of Marian Cove, West Antarctica

Scientific Reports ◽

10.1038/s41598-020-80636-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hanna Bae ◽

In-Young Ahn ◽

Jinsoon Park ◽

Sung Joon Song ◽

Junsung Noh ◽

...

Keyword(s):

Community Structure ◽

Benthic Community ◽

Adaptive Strategy ◽

Ecological Impacts ◽

Glacier Retreat ◽

Benthic Diatoms ◽

Subtidal Zone ◽

Benthic Community Structure ◽

Community Shift ◽

Global Issue

AbstractGlacier retreat is a major long-standing global issue; however, the ecological impacts of such retreats on marine organisms remain unanswered. Here, we examined changes to the polar benthic community structure of “diatoms” under current global warming in a recently retreated glacial area of Marian Cove, Antarctica. The environments and spatiotemporal assemblages of benthic diatoms surveyed in 2018–2019 significantly varied between the intertidal (tidal height of 2.5 m) and subtidal zone (10 and 30 m). A distinct floral distribution along the cove (~ 4.5 km) was characterized by the adaptive strategy of species present, with chain-forming species predominating near the glacier. The predominant chain-forming diatoms, such as Fragilaria striatula and Paralia sp., are widely distributed in the innermost cove over years, indicating sensitive responses of benthic species to the fast-evolving polar environment. The site-specific and substrate-dependent distributions of certain indicator species (e.g., F. striatula, Navicula glaciei, Cocconeis cf. pinnata) generally reflected such shifts in the benthic community. Our review revealed that the inner glacier region reflected trophic association, featured with higher diversity, abundance, and biomass of benthic diatoms and macrofauna. Overall, the polar benthic community shift observed along the cove generally represented changing environmental conditions, (in)directly linked to ice-melting due to the recent glacier retreat.

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Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry

Journal of Glaciology ◽

10.1017/jog.2021.8 ◽

2021 ◽

pp. 1-27

Author(s):

H. Jay Zwally ◽

John W. Robbins ◽

Scott B. Luthcke ◽

Bryant D. Loomis ◽

Frédérique Rémy

Keyword(s):

Mass Balance ◽

Antarctic Peninsula ◽

East Antarctica ◽

Mantle Material ◽

West Antarctica ◽

Mantle Viscosity ◽

Grounding Line ◽

The Antarctic ◽

Total Gain

Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Antarctica (EA) and 4.51 times over West Antarctica (WA), with inferred mantle densities 4.75 and 4.11 g cm−3. Derived sensitivities (Sg, Sa) to bedrock motion enable calculation of motion (δB0) needed to equalize GRACE and ICESat mass changes during 2003–08. For EA, δB0 is −2.2 mm a−1 subsidence with mass matching at 150 Gt a−1, inland WA is −3.5 mm a−1 at 66 Gt a−1, and coastal WA is only −0.35 mm a−1 at −95 Gt a−1. WA subsidence is attributed to low mantle viscosity with faster responses to post-LGM deglaciation and to ice growth during Holocene grounding-line readvance. EA subsidence is attributed to Holocene dynamic thickening. With Antarctic Peninsula loss of −26 Gt a−1, the Antarctic total gain is 95 ± 25 Gt a−1 during 2003–08, compared to 144 ± 61 Gt a−1 from ERS1/2 during 1992–2001. Beginning in 2009, large increases in coastal WA dynamic losses overcame long-term EA and inland WA gains bringing Antarctica close to balance at −12 ± 64 Gt a−1 by 2012–16.

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Seasonality and Dynamics of Atmospheric Teleconnection from the Tropical Indian Ocean and the Western Pacific to West Antarctica

Atmosphere ◽

10.3390/atmos12070849 ◽

2021 ◽

Vol 12 (7) ◽

pp. 849

Author(s):

Hyun-Ju Lee ◽

Emilia-Kyung Jin

Keyword(s):

Indian Ocean ◽

Rossby Wave ◽

Tropical Indian Ocean ◽

Western Pacific ◽

Tropical Region ◽

Formation Mechanisms ◽

West Antarctica ◽

Background Flow ◽

The Impact ◽

The Western Pacific

The global impact of the tropical Indian Ocean and the Western Pacific (IOWP) is expected to increase in the future because this area has been continuously warming due to global warming; however, the impact of the IOWP forcing on West Antarctica has not been clearly revealed. Recently, ice loss in West Antarctica has been accelerated due to the basal melting of ice shelves. This study examines the characteristics and formation mechanisms of the teleconnection between the IOWP and West Antarctica for each season using the Rossby wave theory. To explicitly understand the role of the background flow in the teleconnection process, we conduct linear baroclinic model (LBM) simulations in which the background flow is initialized differently depending on the season. During JJA/SON, the barotropic Rossby wave generated by the IOWP forcing propagates into the Southern Hemisphere through the climatological northerly wind and arrives in West Antarctica; meanwhile, during DJF/MAM, the wave can hardly penetrate the tropical region. This indicates that during the Austral winter and spring, the IOWP forcing and IOWP-region variabilities such as the Indian Ocean Dipole (IOD) and Indian Ocean Basin (IOB) modes should paid more attention to in order to investigate the ice change in West Antarctica.

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A Joint Inversion Estimate of Antarctic Ice Sheet Mass Balance Using Multi-Geodetic Data Sets

Remote Sensing ◽

10.3390/rs11060653 ◽

2019 ◽

Vol 11 (6) ◽

pp. 653 ◽

Cited By ~ 1

Author(s):

Chunchun Gao ◽

Yang Lu ◽

Zizhan Zhang ◽

Hongling Shi

Keyword(s):

Mass Balance ◽

Joint Inversion ◽

Ice Sheet ◽

Mass Change ◽

West Antarctica ◽

Amundsen Sea ◽

Antarctic Ice Sheet ◽

Forward Models ◽

Uplift Rates ◽

The Antarctic

Many recent mass balance estimates using the Gravity Recovery and Climate Experiment (GRACE) and satellite altimetry (including two kinds of sensors of radar and laser) show that the ice mass of the Antarctic ice sheet (AIS) is in overall decline. However, there are still large differences among previously published estimates of the total mass change, even in the same observed periods. The considerable error sources mainly arise from the forward models (e.g., glacial isostatic adjustment [GIA] and firn compaction) that may be uncertain but indispensable to simulate some processes not directly measured or obtained by these observations. To minimize the use of these forward models, we estimate the mass change of ice sheet and present-day GIA using multi-geodetic observations, including GRACE and Ice, Cloud and land Elevation Satellite (ICESat), as well as Global Positioning System (GPS), by an improved method of joint inversion estimate (JIE), which enables us to solve simultaneously for the Antarctic GIA and ice mass trends. The GIA uplift rates generated from our JIE method show a good agreement with the elastic-corrected GPS uplift rates, and the total GIA-induced mass change estimate for the AIS is 54 ± 27 Gt/yr, which is in line with many recent GPS calibrated GIA estimates. Our GIA result displays the presence of significant uplift rates in the Amundsen Sea Embayment of West Antarctica, where strong uplift has been observed by GPS. Over the period February 2003 to October 2009, the entire AIS changed in mass by −84 ± 31 Gt/yr (West Antarctica: −69 ± 24, East Antarctica: 12 ± 16 and the Antarctic Peninsula: −27 ± 8), greater than the GRACE-only estimates obtained from three Mascon solutions (CSR: −50 ± 30, JPL: −71 ± 30, and GSFC: −51 ± 33 Gt/yr) for the same period. This may imply that single GRACE data tend to underestimate ice mass loss due to the signal leakage and attenuation errors of ice discharge are often worse than that of surface mass balance over the AIS.

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