Radio echo sounding map of Antarctica, (˜90°E–180°)

Polar Record ◽  
1975 ◽  
Vol 17 (109) ◽  
pp. 359-374 ◽  
Author(s):  
David J. Drewry
Keyword(s):  
Task Force ◽  
Ice Sheet ◽  
Antarctic Ice Sheet ◽  
Natural Environment Research Council ◽  
The Us ◽  
Radio Echo Sounding ◽  
Polar Research Institute ◽  
Antarctic Research ◽  
Logistic Support ◽  
The Antarctic

In 1967 the Scott Polar Research Institute (SPRI) undertook the first longrange airborne radio echo soundings of the Antarctic ice sheet. The results of this season were encouraging and led to other programmes being organized in 1969–70, 1971–72, and 1974–75. The initial impetus for this work came from A. P. Crary of the US National Science Foundation (NSF), who suggested that the radio echo equipment that had been developed at SPRI under the direction of S. Evans and G. de Q. Robin, with financial assistance from the Royal Society's Paul Instrument Fund and later from the Natural Environment Research Council (NERC) should be operated over the Antarctic ice sheet, and he offered the logistic support of the US Antarctic Research Program (USARP). Since those early flights, a productive relationship has been developed between SPRI and that arm of NSF represented by USARP and US Navy Task Force 43 (now 199) and, up to the end of the 1971–72 season, it had resulted in 210000 km of radio echo profiling in the Antarctic. A further 135 000 km was accomplished during the 1974–75 season.

Radio echo and magnetic sounding of the Antarctic ice sheet, 1978–79

Polar Record ◽  
1980 ◽  
Vol 20 (124) ◽  
pp. 43-51 ◽  
Author(s):  
D. J. Drewry ◽  
D. T. Meldrum ◽  
E. Jankowski
Keyword(s):  
National Science Foundation ◽  
Ice Sheet ◽  
Geophysical Investigation ◽  
Antarctic Ice Sheet ◽  
The Us ◽  
National Science ◽  
Radio Echo Sounding ◽  
Polar Research Institute ◽  
The Antarctic

During December 1978 the Scott Polar Research Institute (SPRI) undertook its sixth and final season of long-range airborne radio echo sounding (RES) and magnetometry in Antarctica in cooperation with the US National Science Foundation Division of Polar Programmes (NSF-DPP) and the Electromagnetics Institute of the Technical University of Denmark (TUD). The 1978–79 season (DF–79) was part of a long-term programme of glaciological and geophysical investigation of the Antarctic ice sheet (Drewry and Meldrum 1978a; 1978b). The broad aims have been to extend a 100-km grid network over Antarctica for a study of surface form, thickness, internal structure, rheology, thermodynamics, electrical properties, basal conditions and processes, and sub-ice geology.

scholarly journals Driving Stresses in the Antarctic Ice Sheet

1982 ◽  
Vol 3 ◽  
pp. 59-64 ◽  
Author(s):  
A. P. R. Cooper ◽  
N. F. Mclntyre ◽  
G. de Q. Robin
Keyword(s):  
National Science Foundation ◽  
Ice Sheet ◽  
Antarctic Ice Sheet ◽  
Bedrock Topography ◽  
Basal Ice ◽  
The Us ◽  
Polar Research Institute ◽  
Ice Velocity ◽  
Stress Variations ◽  
The Antarctic

Radio echo-soundings obtained during joint programmes of the US National Science Foundation (NSF), the Scott Polar Research Institute (SPRI), and the Technical University of Denmark (TUD) have provided sufficient data of good quality to map driving stress over approximately one half of the Antarctic ice sheet. Computerized averaging of data over 1 degree of latitude squares has largely eliminated local effects of longitudinal stress variations on surface slope. Methods of data handling are outlined. Variations in driving stresses between different regions are discussed in relation to the balancing restraining forces. These are primarily related to ice velocity and thickness, bedrock topography, the presence of basal water and possibly to the development of easy-glide fabric in the ice mass, to the temperature of basal ice layers, and to the excess hydrostatic pressure in areas where ice rests on bedrock well below sea-level.

scholarly journals Driving Stresses in the Antarctic Ice Sheet

1982 ◽  
Vol 3 ◽  
pp. 59-64 ◽  
Author(s):  
A. P. R. Cooper ◽  
N. F. Mclntyre ◽  
G. de Q. Robin
Keyword(s):  
National Science Foundation ◽  
Ice Sheet ◽  
Antarctic Ice Sheet ◽  
Bedrock Topography ◽  
Basal Ice ◽  
The Us ◽  
Polar Research Institute ◽  
Ice Velocity ◽  
Stress Variations ◽  
The Antarctic

Radio echo-soundings obtained during joint programmes of the US National Science Foundation (NSF), the Scott Polar Research Institute (SPRI), and the Technical University of Denmark (TUD) have provided sufficient data of good quality to map driving stress over approximately one half of the Antarctic ice sheet. Computerized averaging of data over 1 degree of latitude squares has largely eliminated local effects of longitudinal stress variations on surface slope. Methods of data handling are outlined. Variations in driving stresses between different regions are discussed in relation to the balancing restraining forces. These are primarily related to ice velocity and thickness, bedrock topography, the presence of basal water and possibly to the development of easy-glide fabric in the ice mass, to the temperature of basal ice layers, and to the excess hydrostatic pressure in areas where ice rests on bedrock well below sea-level.

scholarly journals Measured Properties of the Antarctic Ice Sheet: Surface Configuration, Ice Thickness, Volume and Bedrock Characteristics

1982 ◽  
Vol 3 ◽  
pp. 83-91 ◽  
Author(s):  
D.J. Drewry ◽  
S.R. Jordan ◽  
E. Jankowski
Keyword(s):  
Ice Sheet ◽  
Reference Level ◽  
Ice Streams ◽  
Antarctic Ice Sheet ◽  
Frequency Distributions ◽  
Ice Shelves ◽  
Sheet Surface ◽  
Radio Echo Sounding ◽  
Data Points ◽  
The Antarctic

Results of airborne radio echo-sounding (RES) in Antarctica are presented. Flight tracks covering 50% of the Antarctic Ice sheet on a 50 to 100 km square grid, flown using Inertial navigation, have errors <<5 km. Ice thicknesses determined from 35, 60, and 300 MHz RES records are accurate to 10 m or 1.5% thickness (whichever is greater). Altimetry, determining surface and sub-surface elevations, after corrections have errors <<50 m. An up-to-date coastline compiled from satellite imagery and all recent sources has frequencies for various coastal types of: ice shelves (44%), ice streams/outlet glaciers (13%), ice walls (38%), and rocks (5%). A new map of the ice sheet surface has been compiled from 101 000 RES data points, 5 000 Tropical Wind, Energy conversion and Reference Level Experiment (TWERLE) balloon altimetry points, geodetic satellite and selected traverse elevations. The volume of the Antarctic ice sheet Including ice shelves has been calculated principally from RES data using various techniques as 30.11±2.5 × 106 km3. Frequency distributions for subgladal bedrock elevations for East and West Antarctica are presented. They conform approximately to Gaussian (normal) functions.

scholarly journals Measured Properties of the Antarctic Ice Sheet: Surface Configuration, Ice Thickness, Volume and Bedrock Characteristics

1982 ◽  
Vol 3 ◽  
pp. 83-91 ◽  
Author(s):  
D.J. Drewry ◽  
S.R. Jordan ◽  
E. Jankowski
Keyword(s):  
Ice Sheet ◽  
Reference Level ◽  
Ice Streams ◽  
Antarctic Ice Sheet ◽  
Frequency Distributions ◽  
Ice Shelves ◽  
Sheet Surface ◽  
Radio Echo Sounding ◽  
Data Points ◽  
The Antarctic

Results of airborne radio echo-sounding (RES) in Antarctica are presented. Flight tracks covering 50% of the Antarctic Ice sheet on a 50 to 100 km square grid, flown using Inertial navigation, have errors &lt;&lt;5 km. Ice thicknesses determined from 35, 60, and 300 MHz RES records are accurate to 10 m or 1.5% thickness (whichever is greater). Altimetry, determining surface and sub-surface elevations, after corrections have errors &lt;&lt;50 m. An up-to-date coastline compiled from satellite imagery and all recent sources has frequencies for various coastal types of: ice shelves (44%), ice streams/outlet glaciers (13%), ice walls (38%), and rocks (5%). A new map of the ice sheet surface has been compiled from 101 000 RES data points, 5 000 Tropical Wind, Energy conversion and Reference Level Experiment (TWERLE) balloon altimetry points, geodetic satellite and selected traverse elevations. The volume of the Antarctic ice sheet Including ice shelves has been calculated principally from RES data using various techniques as 30.11±2.5 × 106km3. Frequency distributions for subgladal bedrock elevations for East and West Antarctica are presented. They conform approximately to Gaussian (normal) functions.

Dome Fuji Station in East Antarctica and the Japanese Antarctic Research Expedition

2012 ◽  
Vol 8 (S288) ◽  
pp. 161-168 ◽  
Author(s):  
Kazuyuki Shiraishi
Keyword(s):  
General Scheme ◽  
Ice Sheet ◽  
Ice Cores ◽  
Climatic Conditions ◽  
East Antarctica ◽  
Potential Candidate ◽  
Syowa Station ◽  
Antarctic Ice Sheet ◽  
Antarctic Research ◽  
The Antarctic

AbstractJapanese Antarctic Research Expedition (JARE) commenced on the occasion of International Geophysical Year in 1957–1958. Syowa Station, the primary station for JARE operations, is located along the northeastern coastal region of Lützow-Holm Bay, East Antarctica (69° 00′S, 39° 35′E), and was opened on 29 January 1957. Since then, JARE have been carrying out research in various fields of earth and planetary sciences and life science. Astronomical science, however, has not been popular in Antarctica. In 1995, JARE established a new inland station, Dome Fuji Station (77° 19′S, 39° 42′E), which, at 3,810 m a.s.l., is located on one of major domes of the Antarctic ice sheet, some 1,000 km south of Syowa. The climatic conditions at Dome Fuji are harsh, with an annual average air temperature of −54°C, and a recorded minimum of −79°C. In 2007, JARE completed scientific drilling to obtain ice core samples of the Antarctic ice sheet reaching 3,050 m in depth. These ice cores record environmental conditions of the earth extending back some 720,000 B.P. In recent years, it is widely known that the high-altitude environment of inland Antarctica is suitable for astronomical observations and the Japanese astronomy community identified Dome Fuji Station as a potential candidate for a future astronomical observatory. In this article, the history of Japanese Antarctic activities are described in terms of access to the inland plateau of the Antarctic continent. The general scheme and future plans of science objectives and logistics of JARE will also be introduced.

On the origin, nature and uses of Antarctic ice-sheet radio-echo layering

1999 ◽  
Vol 23 (2) ◽  
pp. 159-179 ◽  
Author(s):  
Martin J. Siegert
Keyword(s):  
Numerical Models ◽  
Three Dimensional ◽  
Ice Sheet ◽  
Ice Cores ◽  
Internal Layers ◽  
Antarctic Ice Sheet ◽  
Ice Surface ◽  
Geological Features ◽  
Radio Echo Sounding ◽  
The Antarctic

Airborne radio-echo sounding (RES) data display layering within the Antarctic ice sheet. At ice depths below 1000m these layers are caused by horizons of ice with relatively high acidity which were originally deposited on the ice surface after large volcanic events. Layering which is less than 1000 m from the ice surface can also be due to variation in ice density. Theoretically, therefore, internal RES layering below 1000 m should represent isochronous planes. This theory is upheld under examination of existing RES data where internal layers have been observed to follow the rules of superposition. For example, RES layers are deposited as discrete bands, fold and fault in a manner analogous to geological features, never cross over each other and, in an undisturbed deposit, have a depth-age relationship which means that the oldest layers are located at the lowest level. Moreover, the location of internal layering is independent of radiowave receiver altitude, the frequency of the radiowave does not affect layer depth, and the pulse width of the e/m wave does not affect identification of layers. Thus, RES reflects actual dielectric layering within the ice sheet. Glaciologists use RES layering for a number of reasons, including: (1) correlating ice cores; (2) as boundary conditions for numerical models to help determine the direction of ice flow; and (3) as a means of identifying the three-dimensional ice-sheet geometry and architecture.

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