Snow accumulation variability in Wilkes Land, East Antarctica, and the relationship to atmospheric ridging in the 130°-170°E region since 1930

Abstract. Antarctic ice core nitrate (NO3-) can provide a unique record of the atmospheric reactive nitrogen cycle. However, the factors influencing the deposition and preservation of NO3- at the ice sheet surface must first be understood. Therefore, an intensive program of snow and atmospheric sampling was made on a traverse from the coast to the ice sheet summit, Dome A, East Antarctica. Snow samples in this observation include 120 surface snow samples (top ∼ 3 cm), 20 snow pits with depths of 150 to 300 cm, and 6 crystal ice samples (the topmost needle-like layer on Dome A plateau). The main purpose of this investigation is to characterize the distribution pattern and preservation of NO3- concentrations in the snow in different environments. Results show that an increasing trend of NO3- concentrations with distance inland is present in surface snow, and NO3- is extremely enriched in the topmost crystal ice (with a maximum of 16.1 µeq L−1). NO3- concentration profiles for snow pits vary between coastal and inland sites. On the coast, the deposited NO3- was largely preserved, and the archived NO3- fluxes are dominated by snow accumulation. The relationship between the archived NO3- and snow accumulation rate can be depicted well by a linear model, suggesting a homogeneity of atmospheric NO3- levels. It is estimated that dry deposition contributes 27–44 % of the archived NO3- fluxes, and the dry deposition velocity and scavenging ratio for NO3- were relatively constant near the coast. Compared to the coast, the inland snow shows a relatively weak correlation between archived NO3- and snow accumulation, and the archived NO3- fluxes were more dependent on concentration. The relationship between NO3- and coexisting ions (nssSO42-, Na+ and Cl−) was also investigated, and the results show a correlation between nssSO42- (fine aerosol particles) and NO3- in surface snow, while the correlation between NO3- and Na+ (mainly associated with coarse aerosol particles) is not significant. In inland snow, there were no significant relationships found between NO3- and the coexisting ions, suggesting a dominant role of NO3- recycling in determining the concentrations.

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Simulation of the net snow accumulation along the Wilkes Land transect, Antarctica, with a regional climate model

Annals of Glaciology ◽

10.3189/172756405781813230 ◽

2005 ◽

Vol 41 ◽

pp. 17-22 ◽

Cited By ~ 33

Author(s):

Hubert Gallée ◽

Vincent Peyaud ◽

Ian Goodwin

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Regional Climate ◽

Field Measurements ◽

Snow Accumulation ◽

East Antarctica ◽

Climate Modelling ◽

Surface Mass ◽

Spatial Coverage ◽

Wilkes Land

AbstractRegional climate modelling in conjunction with accumulation measurements collected on Antarctic traverses of the International Trans-Antarctic Scientific Expedition (ITASE) is presented as a tool for extending the spatial coverage of field measurements. The modelling of part of East Antarctica spanned the 7 year epoch 1980–86 where data covering the same period are available. The agreement between simulation and observation is improved when a parameterization of the snow surface redistribution processes, such as wind erosion, is included in the regional climate model. The modelled spatial distribution of the net snow mass transported in the boundary layer over coastal East Antarctica indicates that this mass is a significant component of the surface mass balance.

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Clay mineral fluctuations and surface textural analysis of quartz grains in Pliocene–Quaternary marine sediments from Wilkes Land continental rise (East-Antarctica): Paleoenvironmental significance

Marine Geology ◽

10.1016/j.margeo.2005.11.002 ◽

2006 ◽

Vol 226 (3-4) ◽

pp. 281-295 ◽

Cited By ~ 24

Author(s):

Damiano Damiani ◽

Giovanna Giorgetti ◽

Isabella Memmi Turbanti

Keyword(s):

Clay Mineral ◽

Marine Sediments ◽

Textural Analysis ◽

East Antarctica ◽

Continental Rise ◽

Wilkes Land ◽

Quartz Grains

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The role of atmospheric rivers in anomalous snow accumulation in East Antarctica

Geophysical Research Letters ◽

10.1002/2014gl060881 ◽

2014 ◽

Vol 41 (17) ◽

pp. 6199-6206 ◽

Cited By ~ 104

Author(s):

Irina V. Gorodetskaya ◽

Maria Tsukernik ◽

Kim Claes ◽

Martin F. Ralph ◽

William D. Neff ◽

...

Keyword(s):

Snow Accumulation ◽

East Antarctica ◽

Atmospheric Rivers

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Reconstructing Antarctic snow accumulation using nitrogen isotopes of nitrate

10.5194/egusphere-egu21-672 ◽

2021 ◽

Author(s):

Pete D. Akers ◽

Joël Savarino ◽

Nicolas Caillon ◽

Mark Curran ◽

Tas Van Ommen

Keyword(s):

Nitrogen Isotopes ◽

Full Range ◽

Ice Core ◽

Ice Cores ◽

Snow Accumulation ◽

East Antarctica ◽

Accumulation Rates ◽

Sea Levels ◽

Antarctic Snow ◽

Parallel Reconstruction

Precise Antarctic snow accumulation estimates are needed to understand past and future changes in global sea levels, but standard reconstructions using water isotopes suffer from competing isotopic effects external to accumulation. We present here an alternative accumulation proxy based on the post-depositional photolytic fractionation of nitrogen isotopes (d15N) in nitrate. On the high plateau of East Antarctica, sunlight penetrating the uppermost snow layers converts snow-borne nitrate into nitrogen oxide gas that can be lost to the atmosphere. This nitrate loss favors 14NO3- over 15NO3-, and thus the d15N of nitrate remaining in the snow will steadily increase until the nitrate is eventually buried beneath the reach of light. Because the duration of time until burial is dependent upon the rate of net snow accumulation, sites with lower accumulation rates have a longer burial wait and thus higher d15N values. A linear relationship (r2 = 0.86) between d15N and net accumulation-1 is calculated from over 120 samples representing 105 sites spanning East Antarctica. These sites largely encompass the full range of snow accumulation rates observed in East Antarctica, from 25 kg m-2 yr-1 at deep interior sites to >400 kg m-2 yr-1 at near coastal sites. We apply this relationship as a transfer function to an Aurora Basin ice core to produce a 700-year record of accumulation changes. Our nitrate-based estimate compares very well with a parallel reconstruction for Aurora Basin that uses volcanic horizons and ice-penetrating radar. Continued improvements to our database may enable precise independent estimates of millennial-scale accumulation changes using deep ice cores such as EPICA Dome C and Beyond EPICA-Oldest Ice.

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Review of "Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, and the long-term speed-up of Holmes Glacier"

10.5194/tc-2016-151-rc1 ◽

2016 ◽

Author(s):

Allen Pope

Keyword(s):

East Antarctica ◽

Wilkes Land ◽

Speed Up

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Enhanced Moisture Delivery into Victoria Land, East Antarctica During the Early Last Interglacial: Implications for West Antarctic Ice Sheet Stability

10.5194/cp-2021-7 ◽

2021 ◽

Author(s):

Yuzhen Yan ◽

Nicole E. Spaulding ◽

Michael L. Bender ◽

Edward J. Brook ◽

John A. Higgins ◽

...

Keyword(s):

Accumulation Rate ◽

Ice Cores ◽

Snow Accumulation ◽

East Antarctica ◽

Ice Age ◽

Accumulation Rates ◽

Last Interglacial ◽

Ice Shelf ◽

Ross Ice Shelf ◽

Victoria Land

Abstract. The S27 ice core, drilled in the Allan Hills Blue Ice Area of East Antarctica, is located in Southern Victoria Land ~80 km away from the present-day northern edge of the Ross Ice Shelf. Here, we utilize the reconstructed accumulation rate of S27 covering the Last Interglacial (LIG) period between 129 and 116 thousand years before present (ka) to infer moisture transport into the region. The accumulation rate is based on the ice age-gas age differences calculated from the ice chronology, which is constrained by the stable water isotopes of the ice, and an improved gas chronology based on measurements of oxygen isotopes of O2 in the trapped gases. The peak accumulation rate in S27 occurred at 128.2 ka, near the peak LIG warming in Antarctica. Even the most conservative estimate yields a six-fold increase in the accumulation rate in the LIG, whereas other Antarctic ice cores are typically characterized by a glacial-interglacial difference of a factor of two to three. While part of the increase in S27 accumulation rates must originate from changes in the large-scale atmospheric circulation, additional mechanisms are needed to explain the large changes. We hypothesize that the exceptionally high snow accumulation recorded in S27 reflects open-ocean conditions in the Ross Sea, created by reduced sea ice extent and increased polynya size, and perhaps by a southward retreat of the Ross Ice Shelf relative to its present-day position near the onset of LIG. The proposed ice shelf retreat would also be compatible with a sea-level high stand around 129 ka significantly sourced from West Antarctica. The peak in S27 accumulation rates is transient, suggesting that if the Ross Ice Shelf had indeed retreated during the early LIG, it would have re-advanced by 125 ka.

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50 years of ice-front changes between the Adélie and Banzare Coasts, East Antarctica

Annals of Glaciology ◽

10.3189/172756402781817897 ◽

2002 ◽

Vol 34 ◽

pp. 235-240 ◽

Cited By ~ 9

Author(s):

Massimo Frezzotti ◽

Marco Polizzi

Keyword(s):

Climate Change ◽

Satellite Images ◽

Regional Climate ◽

Regional Climate Change ◽

East Antarctica ◽

Sea Ice Extent ◽

Wilkes Land ◽

Fast Ice ◽

Cyclical Behaviour ◽

General Reduction

AbstractIce-front change may well be a sensitive indicator of regional climate change. We studied the coastal sector of Wilkes Land, East Antarctica, along the Adélie and Banzare Coasts, extending from Buchanan Bay (67°05’ S, 144°30’ E) to Porpoise Bay (67°S, 128°E). The glaciers in this area drain the northern part of Dome C (area 270 000 km2). A comparison of maps, photographs and satellite images, dated several years apart, led to an estimation of the fluctuations of 18 ice fronts over the 50 years 1947–97 .The area of the floating glaciers in 1963 was 3035 km2, and in 1989, 2785 km2. The main glaciers in the area are Zélée, Astrolabe, du Français, Commandant Charcot and Pourquoi Pas for the Adélie Coast, and Dibble, May, Sandford and Frost Glaciers for the Clarie and Banzare Coasts. Most of the floating glaciers have shown cyclical behaviour without a marked trend, but a general reduction since 1947. The reduction in the area of floating glaciers since the 1950s may be linked to changes in ice–ocean interaction, as noted for the floating glaciers of the George V Coast and the Cape Adare area, and sea-ice extent. The calving behaviour of the main glacier tongues is characterized by an accumulation of icebergs projecting from the coast to form iceberg tongues, held in place by grounding and joined together by annual or perennial fast ice.

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On the Relationship of Snow Accumulation to Surface Topography at “Byrd Station”, Antarctica

Journal of Glaciology ◽

10.3189/s0022143000018906 ◽

1965 ◽

Vol 5 (42) ◽

pp. 843-847 ◽

Cited By ~ 5

Author(s):

Anthony J. Gow ◽

Robert Rowland

Keyword(s):

Surface Topography ◽

Current Knowledge ◽

Snow Accumulation ◽

And Migration ◽

Relationship Of ◽

The Relationship

AbstractRecent measurements of snow accumulation on undulating surfaces around “Byrd station”, Antarctica indicate that the undulations are tending to be filled in. These results are discussed in the light of current knowledge of the origin and migration of such features.

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Simultaneous VHF radar backscatter and ionosonde observations of low-latitude E region

Annales Geophysicae ◽

10.5194/angeo-23-773-2005 ◽

2005 ◽

Vol 23 (3) ◽

pp. 773-779 ◽

Cited By ~ 8

Author(s):

A. K. Patra ◽

S. Sripathi ◽

P. B. Rao ◽

K. S. V. Subbarao

Keyword(s):

Low Latitude ◽

Vhf Radar ◽

Radar Echoes ◽

First Results ◽

E Region ◽

Gradient Drift ◽

Drift Instability ◽

Relationship Of ◽

The Relationship ◽

Field Aligned Irregularities

Abstract. The first results of simultaneous observations made on the low-latitude field-aligned irregularities (FAI) using the MST radar located at Gadanki (13.5° N, 79.2° E, dip 12.5°) and the Es parameters using an ionosonde at a nearby station Sriharikota (13.7° N, 80.1° E, dip 12.6°) are presented. The observations show that while the height of the most intense radar echoes is below the virtual height of Es (h'Es) during daytime, it is found to be either below or above during nighttime. The strength of the FAI is better correlated with the top penetration frequency (ftEs) and the blanketing frequency (fbEs) during the night (r=0.4 in both cases) as compared to the day (r=0.35 and -0.04, respectively). Furthermore, the signal strength of FAI is reasonably correlated with (ftEs-fbEs) during daytime (r=0.59) while very poorly correlated during nighttime (r=0.18). While the radar observations in general appear to have characteristics close to that of mid-latitudes, the relationship of these with the Es parameters are poorer than that of mid-latitudes. The observations reported here, nevertheless, are quite consistent with the expectations based on the gradient drift instability mechanism.

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