Finding Antarctica’s Pole of Inaccessibility

Abstract Antarctica’s Pole of Inaccessibility (Southern Pole of Inaccessibility (SPI)) is the point on the Antarctic continent farthest from its edge. Existing literature exhibits disagreement over its location. Using two revisions of the Scientific Committee on Antarctic Research’s Antarctic Digital Database, we calculate modern-day positions for the SPI around 10 years apart, based on the position of the “outer” Antarctic coastline, i.e. its boundary with the ocean. These show that the position of the SPI in the year 2010 was around 83° 54’ S, 64° 53’ E, shifting on the order of 1 km per year as a result of changes of a similar magnitude in the Amery, Ronne-Filchner and Ross Ice Shelves. Excepting a position of the SPI calculated by British Antarctic Survey in 2005, to which it is very close, our newly calculated position differs by 150–900 km from others reported in the literature. We also consider the “inner” SPI, defined by the coastline with floating ice removed. The position of this SPI in 2010 is estimated as 83°37’ S, 53° 43’ E, differing significantly from other reported positions. Earlier cartographic data are probably not sufficiently accurate to allow its rate of change to be calculated meaningfully.

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Measured properties of the Antarctic ice sheet derived from the SCAR Antarctic digital database

Polar Record ◽

10.1017/s0032247400024268 ◽

1994 ◽

Vol 30 (174) ◽

pp. 201-206 ◽

Cited By ~ 55

Author(s):

Adrian J. Fox ◽

A. Paul ◽

R. Cooper

Keyword(s):

Source Material ◽

Descriptive Statistics ◽

Data Sets ◽

Data Set ◽

Antarctic Ice Sheet ◽

Original Source ◽

Ice Shelves ◽

Digital Database ◽

Constituent Feature ◽

The Antarctic

AbstractThe completion of the SCAR Antarctic digital database (ADD) has provided a new basis for statistical calculations for Antarctica: data-sets are available at the scale of the original source material, and generalised to 1:1,000,000, 1:3,000,000, 1:10,000,000, and 1:30,000,000. The new descriptive statistics presented are based on the ADD 1:1,000,000 data-set since this is the largest scale at which source maps provided complete cover of the coastline and ice-free areas. The statistics include the total length and proportions of coastline types and the total area of Antarctica with the proportions of its constituent feature types. The areas of the Ross and Filchner-Ronne ice shelves have also been computed. Whilst the total area of Antarctica has remained static compared with previous studies, the relative proportions of coastline types and constituent feature types within the total area show significant changes. In particular the calculated area of ice-free ground is only approximately one-seventh of that often quoted from previous studies. The changes reported result from improved mapping, reinterpretation of data, and actual changes of coastline.

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A numerical model of blowing snow around an Antarctic building

Annals of Glaciology ◽

10.1017/s0260305500016669 ◽

1994 ◽

Vol 20 ◽

pp. 341-346

Author(s):

I. Moore ◽

S.D. Mobbs ◽

D.B. Ingham ◽

J.C. King

Keyword(s):

Numerical Model ◽

Qualitative Agreement ◽

Progress Report ◽

Blowing Snow ◽

Ice Shelf ◽

British Antarctic Survey ◽

Drifting Snow ◽

Antarctic Continent ◽

Useful Life ◽

The Antarctic

The accumulation of drifting snow around buildings in regions of severe climate has important implications on their design and location. This paper studies one such building, at a station run by the British Antarctic Survey and located on the Brunt Ice Shelf at the edge of the Antarctic continent. Four previous stations have been built in the area, the buildings of which were designed to become covered in snow and all have been crushed within a few years. The current station, Halley V, consists of three buildings which are all raised from the ice shelf by means of legs. They were designed in such a way that the action of the wind blowing underneath the buildings would keep them-clear of snow. This paper describes a model which predicts the shape and position of drift formation, and then compares the results with those observed at Halley. This model is a first attempt to address the problem and as such the paper can be considered to be a progress report; improvements arc currently being made as part of continuing research. It is found that there is some qualitative agreement and possible reasons for a few quantitative discrepancies are discussed. Both the model and the true data show clearly that the new design is very effective in prolonging the useful life of the buildings.

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Introductory remarks

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1977.0067 ◽

1977 ◽

Vol 279 (963) ◽

pp. 3-3

Keyword(s):

Short Duration ◽

Orkney Islands ◽

British Antarctic Survey ◽

International Geophysical Year ◽

South Orkney Islands ◽

Antarctic Continent ◽

The Antarctic ◽

International Geophysical ◽

Long Term Studies

It is now only 80 years since man first set foot on the Antarctic Continent. Thereafter there were sporadic expeditions from various nations, which were mainly exploratory in the geographical sense although scientific studies were increasingly included. Even so, the area was so vast (13.5 x 10 6 km 2 ; 5 1/4 million square miles), the expeditions so intermittent, widely dispersed and of such short duration (at most two years), that there could be no continuity of observation. Apart from the steady occupation by Argentina since 1904 of the Scottish National Antarctic Expedition’s station in the South Orkney Islands, long-term studies began with a naval operation in 1943, the forerunner of the British Antarctic Survey, and have continued to this day. But really it was not until the International Geophysical Year in 1957/8 that a broad based scientific attack on the continent was made. At that time 12 countries maintained 44 stations, both around the perimeter and in the interior of the continent; today the number is 27.

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A new inventory of mountain glaciers and ice caps for the Antarctic periphery

Annals of Glaciology ◽

10.3189/2013aog63a377 ◽

2013 ◽

Vol 54 (63) ◽

pp. 191-199 ◽

Cited By ~ 31

Author(s):

Andrew Bliss ◽

Regine Hock ◽

J. Graham Cogley

Keyword(s):

Large Fraction ◽

Glacier Mass Balance ◽

Glacier Inventory ◽

Ice Shelves ◽

Ice Caps ◽

Mountain Glaciers ◽

Digital Database ◽

Digital Elevation ◽

Volume Estimates ◽

The Antarctic

AbstractAlthough the glaciers in the Antarctic periphery make up a large fraction of all mountain glaciers and ice caps on Earth, a detailed glacier inventory of the region is lacking. We compile such an inventory, recording areas, area-altitude distributions, terminus characteristics and volume estimates. Glaciers on the mainland are excluded. The inventory is derived from the Antarctic Digital Database and some manual digitization. We additionally rely on satellite imagery, digital elevation models and a flowshed algorithm to classify ice bodies. We find 1133 ice caps and 1619 mountain glaciers covering a total of 132 867 ± 6643 km2. Estimated total volume corresponds to 0.121 ± 0.010 m sea-level equivalent. Of the total glacier area, 99% drains either into ice shelves (63%) or into the ocean (36%). The inventory will provide a database for glacier mass-balance assessments, modelling and projections, and help to reduce the uncertainties in previous studies.

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Coastal complexity of the Antarctic continent

10.5194/essd-2019-142 ◽

2019 ◽

Cited By ~ 1

Author(s):

Richard Porter-Smith ◽

John McKinlay ◽

Alex Fraser ◽

Robert Massom

Keyword(s):

Low Complexity ◽

Quantitative Information ◽

Ecological Processes ◽

Ice Shelves ◽

Multi Scale ◽

Biological Studies ◽

Coastal Margin ◽

Terrestrial Environments ◽

Antarctic Continent ◽

The Antarctic

Abstract. The Antarctic outer coastal margin (i.e., the coastline itself, or the terminus/front of ice shelves, whichever is adjacent to the ocean) is a key interface between the ice-sheet and terrestrial environments and the Southern Ocean. Its physical configuration (including both length scale of variation and orientation/aspect) has direct bearing on several closely associated cryospheric, biological, oceanographical and ecological processes, yet no study has quantified the coastal complexity or orientation of Antarctica’s coastal margin. This first-of-a-kind characterisation of Antarctic coastal complexity aims to address this knowledge gap. We quantify and investigate the physical configuration and complexity of Antarctica’s circumpolar outer coastal margin using a novel, technique based on ∼ 40,000 random points selected along a vector coastline derived from the MODIS Mosaic of Antarctica dataset. At each point, a complexity metric is calculated at length scales from 1 to 256 km, giving a multiscale estimate of the magnitude and direction of undulation or complexity at each point location along the entire coastline. Using a cluster analysis to determine characteristic complexity ‘signatures’ for random nodes, the coastline is found to comprise three basic groups or classes: (i) low complexity at all scales; (ii) most complexity at shorter scales; and (iii) most complexity at longer scales. These classes are somewhat heterogeneously distributed throughout the continent. We also consider bays and peninsulas separately and characterise their multi-scale orientation. This unique dataset and its summary analysis have numerous applications for both geophysical and biological studies and will contribute to Antarctic research requiring quantitative information on, and related to, coastal complexity and configuration. All these data are referenced by https://doi.org/10.26179/5d1af0ba45c03 and are available free of charge at https://data.antarctica.gov.au.

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Continent-wide estimates of Antarctic strain rates from Landsat 8-derived velocity grids

Journal of Glaciology ◽

10.1017/jog.2018.23 ◽

2018 ◽

Vol 64 (244) ◽

pp. 321-332 ◽

Cited By ~ 15

Author(s):

KAREN E. ALLEY ◽

TED A. SCAMBOS ◽

ROBERT S. ANDERSON ◽

HARIHAR RAJARAM ◽

ALLEN POPE ◽

...

Keyword(s):

Strain Rate ◽

Mass Balance ◽

Landsat 8 ◽

Length Scale ◽

Strain Rates ◽

Rheological Models ◽

Ice Shelves ◽

Antarctic Continent ◽

Ice Velocity ◽

The Antarctic

ABSTRACTStrain rates are fundamental measures of ice flow and are used in a wide variety of glaciological applications including investigations of bed properties, calculations of basal mass balance on ice shelves, and constraints on ice rheological models. However, despite their extensive application, strain rates are calculated using a variety of methods and length scales and the details are often not specified. In this study, we compare the results of nominal and logarithmic strain-rate calculations based on a satellite-derived velocity field of the Antarctic ice sheet generated from Landsat 8 satellite data. Our comparison highlights the differences between the two common approaches in the glaciological literature. We evaluate the errors introduced by each approach and their impacts on the results. We also demonstrate the importance of choosing and specifying a length scale over which strain-rate calculations are made, which can strongly influence other derived quantities such as basal mass balance on ice shelves. Finally, we present strain-rate data products calculated using an approximate viscous length-scale with satellite observations of ice velocity for the Antarctic continent.

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Antarctica, one continent or two?

Polar Record ◽

10.1017/s0032247400051457 ◽

1961 ◽

Vol 10 (67) ◽

pp. 335-348 ◽

Cited By ~ 20

Author(s):

Edward Thiel

Keyword(s):

Ice Shelves ◽

Antarctic Continent ◽

The Antarctic ◽

Two Sides

In outline, the Antarctic continent crudely resembles a pear. It is indented on two sides by arms of the ocean, the Ross and Weddell Seas. These indentations are even greater than an outline map would suggest, for the seas extend far toward the interior of the continent beneath the world's two largest floating ice shelves, bearing the names of their respective discoverers, the English sea captain, Ross, and the German explorer, Filchner.

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Coastal complexity of the Antarctic continent

Earth System Science Data ◽

10.5194/essd-13-3103-2021 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3103-3114

Author(s):

Richard Porter-Smith ◽

John McKinlay ◽

Alexander D. Fraser ◽

Robert A. Massom

Keyword(s):

Low Complexity ◽

Ecological Processes ◽

Ice Shelves ◽

Biological Studies ◽

Coastal Margin ◽

Terrestrial Environments ◽

Antarctic Continent ◽

The Antarctic ◽

Unique Dataset

Abstract. The Antarctic outer coastal margin (i.e. the coastline itself or the terminus or front of ice shelves, whichever is adjacent to the ocean) is a key interface between the ice sheet and terrestrial environments and the Southern Ocean. Its physical configuration (including both length scale of variation, orientation, and aspect) has direct bearing on several closely associated cryospheric, biological, oceanographical, and ecological processes, yet no study has quantified the coastal complexity or orientation of Antarctica's coastal margin. This first-of-a-kind characterization of Antarctic coastal complexity aims to address this knowledge gap. We quantify and investigate the physical configuration and complexity of Antarctica's circumpolar outer coastal margin using a novel technique based on ∼ 40 000 random points selected along a vector coastline derived from the MODIS Mosaic of Antarctica dataset. At each point, a complexity metric is calculated at length scales from 1 to 256 km, giving a multiscale estimate of the magnitude and direction of undulation or complexity at each point location along the entire coastline. Using a cluster analysis to determine characteristic complexity “signatures” for random nodes, the coastline is found to comprise three basic groups or classes: (i) low complexity at all scales, (ii) most complexity at shorter scales, and (iii) most complexity at longer scales. These classes are somewhat heterogeneously distributed throughout the continent. We also consider bays and peninsulas separately and characterize their multiscale orientation. This unique dataset and its summary analysis have numerous applications for both geophysical and biological studies. All these data are referenced by https://doi.org/10.26179/5d1af0ba45c03 (Porter-Smith et al., 2019) and are available free of charge at http://data.antarctica.gov.au (last access: 7 June 2021).

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A numerical model of blowing snow around an Antarctic building

Annals of Glaciology ◽

10.3189/1994aog20-1-341-346 ◽

1994 ◽

Vol 20 ◽

pp. 341-346 ◽

Cited By ~ 1

Author(s):

I. Moore ◽

S.D. Mobbs ◽

D.B. Ingham ◽

J.C. King

Keyword(s):

Numerical Model ◽

Qualitative Agreement ◽

Progress Report ◽

Blowing Snow ◽

Ice Shelf ◽

British Antarctic Survey ◽

Drifting Snow ◽

Antarctic Continent ◽

Useful Life ◽

The Antarctic

The accumulation of drifting snow around buildings in regions of severe climate has important implications on their design and location. This paper studies one such building, at a station run by the British Antarctic Survey and located on the Brunt Ice Shelf at the edge of the Antarctic continent. Four previous stations have been built in the area, the buildings of which were designed to become covered in snow and all have been crushed within a few years. The current station, Halley V, consists of three buildings which are all raised from the ice shelf by means of legs. They were designed in such a way that the action of the wind blowing underneath the buildings would keep them-clear of snow.This paper describes a model which predicts the shape and position of drift formation, and then compares the results with those observed at Halley. This model is a first attempt to address the problem and as such the paper can be considered to be a progress report; improvements arc currently being made as part of continuing research. It is found that there is some qualitative agreement and possible reasons for a few quantitative discrepancies are discussed. Both the model and the true data show clearly that the new design is very effective in prolonging the useful life of the buildings.

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Lichens of the Oasis Molodyozhnyi and adjacent areas (Enderby Land, Antarctic)

Novosti sistematiki nizshikh rastenii ◽

10.31111/nsnr/2013.47.167 ◽

2013 ◽

Vol 47 ◽

pp. 167-178 ◽

Cited By ~ 1

Author(s):

M. P. Andreev

Keyword(s):

Liquid Water ◽

Climate Conditions ◽

Water Ice ◽

Buellia Frigida ◽

Antarctic Continent ◽

Harsh Climate ◽

The Antarctic ◽

First Time ◽

Lichen Flora

Lichen flora and vegetation in the vicinity of the Russian base «Molodyozhnaya» (Enderby Land, Antarctica) were investigated in 2010–2011 in details for the first time. About 500 specimens were collected in 100 localities in all available ecotopes. The lichen flora is the richest in the region and numbers 39 species (21 genera, 11 families). The studied vegetation is very poor and sparse, but typical for coastal oases of the Antarctic continent. The poorness is caused by the extremely harsh climate conditions, insufficient availability of liquid water, ice-free land, and high insolation levels. The dominant and most common lichens are Rinodina olivaceobrunnea, Amandinea punctata, Candelariella flava, Physcia caesia, Caloplaca tominii, Lecanora expectans, Caloplaca ammiospila, Lecidea cancriformis, Pseudephebe minuscula, Lecidella siplei, Umbilicaria decussata, Buellia frigida, Lecanora fuscobrunnea, Usnea sphacelata, Lepraria and Buellia spp.

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