Multispectral Landsat 

Images of Antarctica 

Multispectral Landsat 

I mages of Antarctica 

By BAERBEL K. LUCCHITIA, JO-ANN BOWELL, 

KATHLEEN L. EDWARDS, ERIC M. ELIASON, 

and HOLLY M. FERGUSON 

U.S. GEOLOGICAL SURVEY BULLETIN 1696 
DEPARTMENT OF THE INTERIOR 

DONALD PAUL HODEL, Secretary 

U.S. GEOLOGICAL SURVEY 

Dallas L. Peck, Director 

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1987 

For sale by the 

Books and Open-File Reports Section 

U.S. Geological Survey 

Federal Center, Box 25425 

Denver, CO 80225 

Library of Congress Cataloging-in-Publication Data 

Multispectral Landsat images of Antarctica. 

U.S. Geological Survey Bulletin 1696 

Bibliography 

Supt. of Docs. No.: I 19.3:1696 

1. Earth sciences-Antarctic regions. 2. Geological 

mapping-Antarctic regions. 3. Antarctic regionsPhotographs from space. 4. Landsat satellites. I. Lucchitta, 

Baerbel K. II. Series. 

QE75.B9 No. 1696 557.3 s 86-600365 

[QE350] [559.8'9] 
CONTENTS 

Abstract 1 

Introduction 1 

Data acquisition 1 

Historical perspective 2 

Digital-image-processing methods 3 

Special-purpose images 8 

Antarctic meteorites 8 

Glaciological contributions 12 

Coastline changes 12 

Spectral and structural studies 17 

Conclusions 17 

References 20 

FIGURES 

1. Index map of scenes covered by Landsat computer tapes of Antarctica 2 

2. Saturated and saturation-corrected composites of English Coast area 4 

3. Unenhanced print and digitally enhanced composite of Queen Maud Land 6 

4. False-color multispectral digital mosaic of McMurdo Sound region 9 

5. Special-purpose images of Byrd Glacier region 10 

6. False-color multispectral-image map of Convoy Range quadrangle 13 

7. Image showing glaciological features on Ronne Ice Shelf 14 

8. Image showing morphological features in Ellsworth Mountains and on Rutford 

Ice Stream 15 

9. Image showing morphological features in Theron Mountains and on Slessor 

Glacier 16 

10. Enhanced image of Byrd Glacier region 18 

11. False-color, sinusoidally stretched image of McMurdo Sound region and Dry 

Valleys 19 

TABLE 

1. Geographic location of features mentioned in report 3 

Ill 

Multispectral Landsat Images of Antarctica 

By Baerbel K. Lucchitta, Jo-Ann Bowell, Kathleen L. Edwards, Eric M. Eliason, 

and Holly M. Ferguson 

Abstract 

The U.S. Geological Survey has initiated a 

program to map Antarctica by using colored, digitally 

enhanced Landsat multispectral scanner (MSS) images 

to increase existing map coverage and to improve upon 

previously published Landsat maps. After overcoming 

several difficulties, particularly those associated with 

severe saturation of bright, snow-covered scenes in 

spectral bands 4 and 5, we compiled a mosaic image in 

map projection of the McMurdo Sound region. This 

digitally enhanced mosaic covers four complete and 

two partial 1 :ZSO,OOO-scale topographic quadrangles 

and shows significantly more detail in rock and ice 

than do previously compiled black-and-white paperprint mosaics of the region. 

Digitally processed Landsat images can provide 

accurate and detailed base maps, and they may aid in 

solving several Antarctic research problems. Some of 

these problems are addressed in our mapping program; 

results are given in this report. We prepared thematic 

images showing either bedrock or ice features only; 

maps from such images will be helpful in locating ice 

or rock in remote areas that are difficult to reach on 

the ground. Images and maps derived from them can 

show blue-ice areas that are easily recognized by their 

distinctive blue color and are important for the 

collection of meteorites. Furthermore, the images 

show--more clearly than previous images--ice rises, 

flow lines on ice streams and ice shelves, and buried 

mountain ranges. The images also reveal that the Byrd 

Glacier has moved at an average velocity of 800 

meters/year within 10 years; monitoring such changes 

in glaciers, ice shelves, and the coastline is useful in 

prediction of climatic changes and possible worldwide 

changes in sea level. We found that the resolution of 

Landsat MSS (about 80 m} is insufficient for most 

detailed spectral studies because almost all rock 

outcrops in Antarctica are small, but we anticipate 

that the resolution of thematic mapper (TM} images 

(about 30 m) will be adequate for such studies in the 

future. 

INTRODUCTION 

Antarctica is the only continent on Earth whose 

physiography and geology remain poorly known. It 

contains vast areas that are not yet shown on maps. 

Therefore, the U.S. Geological Survey (USGS) has 

begun a program to prepare digitally enhanced imagemosaic maps in color from multispectral scanner (MSS) 

Landsat images. In addition to increasing map 

coverage of Antarctica and improving existing maps, 

the image mosaics may enable the following: 

(1) superposition and correlation of different types of 

digital cartographic data; (2) production of specialpurpose images showing only selected features; (3) 

location and delineation of blue-ice areas, where 

meteorites are collected; (4) provision of synoptic 

views that aid in the detection and interpretation of 

glaciological features associated with ice sheets, 

outlet glaciers, ice streams, and ice shelves; (5) 

monitoring of changes in coastlines and glacial 

features; and (6) supplying spectral and structural 

information in areas of limited bedrock outcrop to aid 

in regional geological interpretation. 

During the course of the project, we have 

overcome a number of technical problems, approached 

several of our goals, and assembled a set of 

spectacular images and image mosaics. This report 

summarizes our initial results and illustrates what can 

be achieved with multispectral imaging techniques in 

Antarctica. 

DATA ACQUISITION 

About 170 computer tapes containing digital 

Landsat images have been acquired of the coastal and 

near-coastal areas of Victoria Land, Marie Byrd Land, 

and the Antarctic Peninsula and of selected areas in 

the Ellsworth Mountains, the Shackleton Range, Queen 

Maud Land, and the Lambert Glacier-Amery Ice Shelf 

region (fig. 1). (Locations of named features in this 

report are given in table 1.) These areas were chosen 

because their Landsat images accurately portray 

1 
WEST oo EAST 

EAST ANTARCTICA 

WEST 180° EAST 

Figure 1. Index map of Antarctic scenes covered by Landsat computer tapes acquired by U.S. Geological Survey 

for this study. Boundary of continent shown by heavy line. E, Ellsworth Mountains; S. Shackleton Range; M, 

Queen Maud Land; Y, Yamato Mountains; L, Lambert Glacier-Amery Ice Shelf. Area of McMurdo region mosaic 

(Me), solid black. 

mountain ranges, nunataks, and the coastline (as 

recognized in the early to mid-1970's). Landsat 

coverage extends only to about lat 81° S.; therefore, 

images of large parts of the Transantarctic Mountains 

are not available for analysis. Nevertheless, 79 

percent of Antarctica lies north of lat 81° S., and 55 

percent of the continent is already covered by 

excellent or good images (having less than 10 percent 

clouds) (Williams and others, 1982, 1984). 

2 

HISI'ORICAL PERSPEC'OVH 

Most Landsat images of Antarctica were 

acquired in the early to mid-1970's during a National 

Aeronautics and Space Administration (NASA)-funded 

Earth Resources Technology Satellite (ERT8-l) 

investigation under the leadership of the late William 

R. MacDonald (Southard and MacDonald, 1974). 

MacDonald pioneered the use of Landsat images to 
Table 1. Geographic location of features 

mentioned in report 

Feature 

Allan Hills 

Amery Ice Shelf 

Antarctic Peninsula 

Belgica Mountains 

Byrd Glacier 

Dry Valleys 

East Antarctica 

Ellsworth Mountains 

English Coast 

Erebus Glacier Tongue 

Ferrar Glacier 

Fletcher Ice Rise 

Fowler Ice Rise 

Hatherton Glacier 

Jutulstraumen Glacier 

Kershaw Ice Rumples 

Korff Ice Rise 

Lake Vanda 

Lambert Glacier 

Marie Byrd Land 

McMurdo Sound 

Mount Erebus 

Mulock Glacier 

Pine Island Glacier 

Queen Maud Land 

Ronne Ice Shelf 

Ross Island 

Ross Ice Shelf 

Rutford Ice Stream 

Sentinel Range 

Shackleton Range 

Slessor Glacier 

Spaatz Island 

Theron Mountains 

Transantarctic Mountains 

Victoria Land 

West Antarctica 

Wilkes Land 

Yamato Mountains 

Location (central 

coordinates are given 

for large features) 

76°43 1 s.l 

69°45 1 s.l 

69°30 I s. 1 

72°35 1 s.l 

80°20 I S. 1 

78°00 1 s., 

80°00 I S. 1 

78°45 1 s., 

73°30 I S. 1 

77°42 I S. 1 

77°46 1 s., 

78°20 1 s., 

77°30 I S. 1 

79°55 1 s., 

71°35 1 s., 

78°45 I S. 1 

79°00 I S. 1 

77°32 1 s., 

71°00 1 s., 

80°00 I S. 1 

77°30 I S. 1 

77°32 1 s., 

79°00 I S. 1 

75°10 1 s., 

72°30 I S. 1 

78°30 1 s., 

77°30 I S. 1 

81°30 1 s.' 

79°00 I S. 1 

78°10 1 s., 

80°40 I S. 1 

79°50 1 s., 

73°12 I S. 1 

79°05 1 s., 

85°00 I S. 1 

74°15 1 s., 

79°00 I S. 1 

60°00 1 s., 

71°30 I S. 1 

159°40 1 E. 

71°00 I E. 

65°00 1 w. 

31°15 1 E. 

159°00 1 E. 

161°00 1 E. 

80°00 1 E. 

85°00 1 w. 

73°00 1 w. 

166°40 1 E. 

163°00 1 E. 

81°00 1 w. 

78°00 1 w. 

157°35 I E. 

0°30 1 w. 

75°40 1 w. 

69°30 1 w. 

161°33 I E. 

70°00 1 E. 

120°00 1 w. 

165°00 1 E. 

167°10 I E. 

160°00 1 E. 

100°00 1 w. 

12°00 1 E. 

61°00 1 w. 

168°00 1 E. 

175°00 1 w. 

81°00 1 w. 

85°30 1 w. 

26°00 1 w. 

28°30 1 w. 

75°00 1 w. 

28°15 1 w. 

175°00 1 w. 

163°00 1 E. 

100°00 1 w. 

120°00 1 E. 

35°40 1 E. 

produce Landsat single-scene and multiple-image 

mosaic maps (scale 1:1,000,000) of all coastal areas of 

Antarctica. For mapping purposes, he recognized the 

advantage of Landsat images, because of their 

synoptic view, over conventional images. For 

instance, only 15-20 Landsat images, instead of 12,000 

conventional vertical aerial photographs, are required 

to cover the area of a 1:1,000,000-scale map of the 

International Map of the World (IMW) series 

(MacDonald , 1976a); the small number of images is a 

distinct advantage for Antarctica, where geodetic 

ground control is scarce. MacDonald's maps were 

based on unenhanced images of MSS band 7 (0.8-1.11-lm, 

near-infrared); only five maps were eventually 

published and three additional ones were released as 

poor-quality ozalid reproductions through the USGS 

open-file report series. Unenhanced paper prints of 

individual Landsat images or mosaics have been 

extensively used in the production of preliminary 

planimetric maps at scales of 1:250,000 and 1:500,000 

by the British Antarctic Survey for the Antarctic 

Peninsula and adjacent regions, and by the Australian 

Division of National Mapping for the coastal areas of 

East Antarctica in Wilkes Land. However, unenhanced 

black-and-white paper prints generally produce 

satellite-image maps of lesser quality than can be 

achieved with modern image-processing techniques. 

Digital-image mapping has been done largely for 

single frames, especially by Norway (International 

Business Mac hines, IBM, in Oslo and the Norsk 

Polarinstitutt, 0degaard and Helle, 1982) and by New 

Zealand's Department of Scientific and Industrial 

Research (DSIR). Concurrently with the USGS effort 

in Flagstaff, Arizona, mosaicking by digital-imageprocessing methods is now being attempted by the 

Institut fiir Angewandte Geodaesie of the Federal 

Republic of Germany and by the DSIR of New Zealand 

(Williams and others, 1982). 

DIGITAL-IMAGE-PROCESSING METHODS 

Most Landsat MSS images of Antarctica 

produced by the Flagstaff facility are composites of 

band 4 (0.5-0.61-lm, green), band 5 (0.6-0.71-lm, red), and 

band 7 (0.8-1.1 11m, near infrared). In some images, 

band 5 was saturated, so band 6 (0.7-0.8 11m, near 

infrared) was substituted. Our digital-image 

processing of Landsat images includes routine 

procedures such as radiometric corrections, noise 

removal, and geometric corrections (Chavez and 

others, 1977; Condit and Chavez, 1979). Further 

processing includes haze removal (Chavez, 1975) and 

image enhancement involving customized stretching of 

gray values (digital numbers) of individual MSS bands 

after analysis of gray-value histograms. 

Saturation of snow- and ice-covered scenes in 

bands 4, 5, and 6 (fig. 2A) is a severe problem in 

Landsat MSS images (Dowdeswell and Mcintyre, 1986); 

the saturation makes many images unsuitable for 

multispectral work and can even result in loss of 

information in all four Landsat MSS bands (Ferrigno 

and Williams, 1983). We have developed a restoration 

technique for reconstructing the information lost in 

bands 4 and 5 by such saturation (fig. zm. The 

technique can be applied only if bands 6 and 7 retain 

good information. If an image contains undulating 

terrain, slopes facing away from the Sun have lower 

brightness values and are less subject to saturation 

than flat areas or slopes facing toward the Sun. To a 

first-order approximation, the spectral-color ratios of 

snow and ice are independent of sun-elevation angle. 

During the restoration, images are scanned for 

unsaturated snow and ice areas, and statistical 

relations are established among the band ratios 4/7, 

5/7, and 6/7. From these relations, bands 4 or 5 can be 

predicted as a function of the 6/7 and 4/7 or 5/7 ratios 

and the intensity of band 7. A second pass through the 

data applies these functional relations to saturated 

areas. For images having insufficient areas of 

unsaturated snow and ice, the functional relation from 

other less saturated images can be applied. 

Comparison of an unenhanced paper print of MSS 

band 7 of the Jutulstraumen Glacier in Queen Maud 

Land (fig. 3A) and a digitally enhanced multispectral 

3 
\ 

A 

0 20 KILOMETERS 

Figure 2. Saturated and saturation-corrected composites of bands 4~ 5~ and 7 of Landsat 1 MSS image 1170-

12260, 9 January 1973. Part of base of Antarctic Peninsula; English Coast separates the Antarctic continent on 

right from ice shelf on left. A, Composite of saturated bands 4 and 5 and unsaturated band 7. B, Composite in 

which bands 4 and 5 have beenrestored from information in unsaturated parts of bands 4, 5, 6, and 7; a high-pass 

filter was applied to enhance fine detail. 

4 
Figure 2. Continued. 0 20 KILOMETERS 

5 
0 20 KILOMETERS 

Figure 3. Paper print of unenhanced MSS band 7 (A) and digitally enhanced composite of bands 4, 5, and 7 (B) of 

Landsat 2 MSS image 2281-07 424~ 30 October 1975:" Jutulstraumen Glacier in Queen Maud Land in right center 

of pictures, flowing north. Enhanced image B shows improved definition of flow lines in glacier, wind streaks 

crossing glacier (lower right center), and unduiation of ice sheet. Blue-ice areas (examples indicated by arrows) 

show as blue patches. 
0 20 KILOMETERS 

Figure 3. Continued. 

7 
image of the same scene (fig. 3B) shows that the 

enhanced image provides much moredetail. 

A digitally enhanced mosaic of the McMurdo 

Sound region is shown in figure 4. As is evident in this 

mosaic, the digital method permits the automated 

removal of seams (boundaries between Landsat images) 

and the matching of different tones in the various 

images used to construct the mosaic. Tone matching 

is particularly crucial for images of Antarctica 

because the varied, yet low, solar-elevation angles 

create scenes that differ markedly in spectral 

response. To lighten the dark rocky outcrops and to 

darken the bright sunny areas, we applied a high-pass 

filter and reduced the contrast by 50 percent (Chavez 

and Berlin, 1984). The mosaic shows much more detail 

in rock outcrops of the Dry Valleys than can be seen on 

unenhanced, monochrome Landsat images. 

Furthermore, bare ice can be distinguished from snow 

by its blue color, and fine morphologic features such as 

flow lines and crevasses on glaciers are clearly 

visible. The mosaic is a false-color composite, even 

though the colors look real. In Antarctica, which lacks 

vegetation, false-color images resemble those of true 

color because the false red color that commonly 

reflects vegetation is absent. 

Digital-image processing also permits the placing 

of geodetically controlled mosaics onto map 

projections. The McMurdo mosaic, for instance, is in 

Lambert conformal conic projection and covers the 

area of four complete and two partial 1:250,000-scale 

topographic maps. Where geodetic ground control is 

adequate, the mosaic has a geometric accuracy of an 

average of two to three picture elements (pixels) or 

about 200 m. Digital-image processing also allows the 

construction of hybrid maps, for which images can be 

superposed on other data such as digitized 

topographical, geological, geophysical, geochemical, or 

other remote-sensing information. Superposed data 

sets can be displayed graphically and correlated 

visually or by computer methods. Superposition 

techniques have been used for geologic interpretations 

in areas of the United States (Arvidson and Guinness, 

1981; Trautwein, 1983) but have not yet been tried for 

Antarctica. Several geophysical surveys of Antarctica 

are in progress (Behrendt, 1983) for which our 

digital-image mosaics will serve as planimetric base 

maps for display and correlation of geological, 

geophysical, and glaciological data. 

SPECIAL-PURPOSE IMAGES 

In Antarctica, where vast regions are difficult to 

reach on the ground, the location of features by 

remote-sensing techniques becomes important. To this 

end, the multispectral digital images can be converted 

into thematic images that delineate features of 

interest. Figure 5A shows an image of the Byrd 

Glacier and environs in which soil or rock outcrops are 

highlighted. The image was prepared by first 

producing versions showing the ratios of MSS bands 

4/5, 5/6, and 6/7 for each pixel in the image. An 

unsupervised classification program of the ratioed 

images then separated snow from ice and from soil or 

rock. On the basis of these distinctions, the soil-or8 

rock image was prepared. Each pixel showing soil or 

rock was enlarged to a 5-by-5 pixel area, for easier 

recognition. The image shows that a strip in shadow 

along the north side of the Mulock Glacier contains 

soil or rock exposures that are not plainly visible on 

the original Landsat MSS image. Because atmospheric 

scattering and back lighting cause a shadow on snow to 

have a different signature than a shadow on soil or 

rock, spectral techniques can discriminate these two 

types of materials. Soil or rock maps can thus be 

produced even in areas where much of the surface may 

be in shade because of low solar-elevation angles. 

Ice can also be highlighted in special-purpose 

images (fig. 5B) by the same method. Conspicuous in 

this 11 ice-only" image are the icy parts of the Byrd 

Glacier, which show crevassed areas concentrated in 

the narrowest part of the glacier. 

ANTARCTIC METEORITES 

Of particular interest in recent years has been 

the search for meteorites m Antarctica, and 

multispectral Landsat images may help in this effort. 

About 6,000 meteorite fragments have been recovered 

from Antarctica, mostly in blue-ice areas. Of these 

meteorites, 4,000 were found by Japanese parties 

working in the Yamato and Belgica Mountains and 

1,200 by U.S. scientists near the Allan Hills and other 

areas inland of the Transantarctic Mountains in 

southern Victoria Land (National Science Foundation, 

1981; Bull and Lipschutz, 1982). These numbers 

represent 25 percent of the total meteorite finds on 

Earth (Williams and others, 1983). Olsen (1981) 

estimated that at least 760,000 meteorites are likely 

to lie within the ice sheet of East Antarctica. 

Blue ice is a distinctive turquoise blue. 

Exposures occur in many parts of Antarctica, primarily 

near the coast and in the interior both upstream and 

downwind from nunataks. The ice exposures are 

caused by ablation, which results mainly from 

sublimation, wind scouring of the snow mantle, and 

surface polishing by wind-driven snow (Williams and 

others, 1983). Whillans and Cassidy (1982, 1983) 

proposed a meteorite-concentration mechanism in 

which meteorites fall into accumulation areas and are 

buried. Meteorites are then carried along in the 

moving ice sheets and reappear in the blue-ice areas, 

where the surface is reduced by ablation and the flow 

is highly strained, compressed, and pushed upward 

because of its blockage by transverse mountain 

ranges. Meteorite concentrations are thus a lag 

deposit on blue ice (Marvin, 1982). Areas of high 

strain rates are predictable from the geometry of a 

flow and from the recognition of obstacles and 

entrained debris in the flow path, both of which can be 

identified locally on Landsat images. 

Blue ice shows exceptionally well on 

multispectral Landsat images. The signature of blue 

ice is distinct from that of rock in Landsat MSS bands 

4 and 5; however, the signatures are similar in bands 6 

and 7. Therefore, on paper prints of MSS band 7--used 

extensively in the past--blue ice is difficult to 

differentiate from rock, and misidentifications have 

been made (Southard and MacDonald, 1974). Figure 6 

shows the Allan Hills area of southern Victoria Land 
0 50 KILOMETERS 

Figure 4. False-color multispectral digital mosaic of Me Murdo Sound region in Lambert con formal conic 

projection. Ross Island, snow-covered area in right center, is topped by active volcano Mount Erebus (left 

center of island). McMurdo Station on the island is located at tip of fingerlike peninsula extending toward 

southwest. Ice-free valleys in center of image are Dry Valleys. (Mosaic of Landsat MSS images 1214-20064, 22 

February 1973; 1520-20034, 25 December 1973; 1529-19121, 3 January 1974; 1531-19231, 5 January 1974; 1540-

20141. 14 January 1974; 2279-19361, 28 October 1975; composites of bands 4, 5, and 7.) 9 
0 20 KILOMETERS 

Figure 5. Byrd Glacier region. Band 7 of Landsat 1 MSS image 1542-18435, 16 January 1974. A, Specialpurpose image highlighting areas of soil or rock exposure (red). Note rock exposures in shadow (examples shown 

by arrows). Diffused light and dark areas in top left of picture are clouds and their shadows. Isola ted red spots 

on glaciers are computer errors. ~ Special-purpose image highlighting areas of bare ice (blue) on Hatherton 

Glacier, in highly crevassed area in center of Byrd Glacier, and along edge of crevasses. Blue spots near bottom 

right of image are computer errors. 

10 
0 20 KILOMETERS 

Figure 5. Continued. 

11 
and the blue-ice area where meteorite searches by the 

United States have been targeted (Cassidy, 1979). The 

search efforts have been expanded to other blue-ice 

areas in the vicinity, and the image map shown in 

figure 6 is being used to locate additional areas (W.A. 

Cassidy, University of Pittsburgh, written commun., 

November 25, 1985). Another Landsat image of the 

area was successfully used during the search for 

meteorites in the 1982/83 austral field-work season to 

plot traverses and to identify blue-ice patches where 

meteorites were collected (Meunier, 1983). Special 

blue-ice maps covering all coastal and nuna tak areas 

of Antarctica would be extremely helpful for expanded 

future searches for meteorites. The use of Landsat 

images to prepare these maps was highly recommended 

during a workshop on Antarctic glaciology and 

meteorites (Bull and Lipschutz, 1982). 

GLACIOWGICAL CONTRIBU110NS 

The synoptic view afforded by Landsat images is 

especially useful for the recognition and identification 

of glaciological features. For instance, Orheim (1978) 

found several ice rises on Landsat images of Queen 

Maud Land. Ice rises (figs. 7 and 8) are generally 

ellipsoidal, dome-shaped ice caps grounded on shoals 

within or at the seaward edge of ice shelves 

(Armstrong and others, 1973); they are nourished 

almost exclusively by local accumulation of snow. 

Their shape and dynamics have been studied 

intensively because they are smaller analogs to the 

large ice sheets that cover Antarctica; study of ice 

rises may contribute to a better understanding of the 

flow mechanism of the large sheets (Bentley and 

Giovinetto, 1962; Clapp, 1965; Budd, 1969). A 

controversy has developed concerning the pro files 

across several of these ice rises: Landsat images show 

that many of the rises have distinct rie\5es along their 

crestlines (Martin, 1976), even though flow laws 

predict flattened crests whose slopes are close to 0° 

(Nye, 1959; Paterson, 1981). Martin (1976) proposed 

that a ridged crest indicates that a critical stress in 

the ice has to be reached before the ice begins to 

deform. However, detailed pro files across ice rises, 

prepared in a followup study on the shape and 

dynamics of ice rises (Martin and Sanderson, 1980), 

showed no topographic ridges along their crests. Our 

digitally enhanced Landsat images clearly show not 

just single, but double ridges on several ice rises (figs. 

7 and 8). The ridges are not artifacts, because they 

can be seen in other images taken several years 

apart. The rie\5es follow sweeping, broadly sinuous 

curves along the ice-rise crests. They are superposed 

on topographic irregularities, which suggests that they 

are relatively late, perhaps even ephemeral, features. 

Their apparent youth and sinuous shape suggest that 

they may be caused by wind action, perhaps by a 

combination of wind sculpture and deposition of 

drifts. Mars, whose environment is a cold desert like 

Antarctica, has many sweeping sinuous scarps and 

ridges, which are commonly interpreted as being due 

to eolian processes (Cutts and Blasius, 1981). Future 

ground investigations will have to elucidate the precise 

nature of the ice ridges in Antarctica. The 

configuration of ice-rise crests needs to be determined 

12 

because it affects calculations concerning the mass 

balance of ice caps. 

As pointed out by Swithinbank and Lucchitta 

(1986), digitally enhanced Landsat images show--more 

clearly than previous images-synoptic views of glacial 

flow lines and ice rumples (bedrock highs in the path of 

ice streams and ice shelves over which the ice moves 

and is deflected upward). The Kershaw Ice Rumples 

(bottom of fig. 7) form as a thick ice shelf forces its 

way over a shoal. Crevasse fields on the downstream 

side are also visible. Figure 7 also shows on the Ronne 

Ice Shelf flow lines persisting for hundreds of 

kilometers from their sources. The flow lines 

represent sutures recording the confluence of discrete 

ice streams and the path along which the ice has 

moved (Swithinbank and Lucchitta, 1986). Surface 

markings on ice streams tend to develop transverse 

ridges beyond the grounding line wh~ the ice stream 

begins to float. Divergence of flow lines around subtle 

highs in floating ice streams and ice shelves indicates 

possible places of grounding, and several such sites 

have been detected on our images (fig. 8). The 

location of grounded ice in ice streams and ice shelves 

is important in the analysis of the dynamics of the ice 

sheets, and changes in grounded areas may indicate 

long-term climatic changes (Hughes, 1983). 

Digitally enhanced Landsat images, which show 

subtle relief variations on the ice surface, may also 

delineate the extent of some buried mountain ranges 

and indicate the underlying structure (Marsh, 1985). 

The image in figure 8 shows buried valleys upstream 

from two glaciers that enter the Rut ford Ice Stream 

from the west and also a series of escarpments at the 

edge of the Ellsworth Mountains over which these 

glaciers drop before joining the Rutford Ice Stream. 

At the surface of the Slessor Glacier (fig. 9), a 

pronounced diagonal bedrock structure is clearly 

expressed; the scarp on the glacier is probably the 

surface expression of a fault in the subglacial 

bedrock. In this image buried valleys also show well 

through the ice cover. 

COASTLINE CHANGES 

The synoptic view of Landsat images is well 

suited to the monitoring of dynamic Antarctic features 

such as shorelines, grounding lines, ice-shelf margins, 

position of glacier tongues and ice streams, and seaice distribution. Even though repeated coverage of 

these features using photographs from aircraft would 

serve the same purpose, the logistics of such surveys 

would be difficult; repeated routine coverage by 

satellite at fixed time intervals is definitely 

advantageous. Monitoring the coastline for changes 

with time helps detect changes that re fleet the waxing 

and waning of the ice sheets and that may thus have 

far-reaching implications for world climate. 

MacDonald (1976b) recognized the value of 

Landsat images for the monitoring of coastline 

changes and gave several examples of changes: The 

Erebus Glacier Tongue on Ross Island (fig. 4), which 

broke off in 1911, has advanced 9.6 km between 1947 

and 1972, when the first Antarctic Landsat images 

were acquired. By comparing published maps and 
,.... 

~ 

158° 

,., 

76°15' 

76°30' ,,.... 4 . ,.. ·-'}j _- . 

,t 

-- · 

160° 

:: 

6~ E 

"-.',1 ·,- -.,. ""~ \ .. .... -- 'ill' 

.: v~ ,. 1 

<v .., iiC ~~ 

~ ~~ ~ 

~ 

0 20 KILOMETERS 

Figure 6. False-color multispectral image map of the Convoy Range 

quadrangle, polar stereographic projection. Excerpt of mosaic 

shown in figure 4. Allan Hills are dark horseshoe-shaped rock 

exposure at lat 76°43' S., long 159°40' E. Blue-ice areas are 

turquoise blue. Meteorite-collecting sites in blue-ice patch at 

arrow. Hummocky, striated, light-colored area near top right is 

cloud cover; dark streaks are cloud shadows. (Mosaic of Landsat 

MSS images 1214-20064, 22 February 1973; and 1540-20141, 14 

January 1974; composites of bands 4, 5, and 7.) 
0 20 KILOMETERS 

Figure 7. Glaciological features on Ronne Ice Shelf. Digitally enhanced composite of bands 4, 5, and 7 of 

Landsat 1 MSS image 1570-11031, 13 February 1974. Note double ridge (arrows) on crest of Korff Ice Rise. 

Flow lines trending northeast represent sutures recording confluence of discrete ice streams outside picture. 

Kershaw Ice Rumples show extensive crevasse field at downstream (northeast) side. Dark patches at bottom left 

are of unknown origin, but they could represent thin layer of drifting snow or area of recently deposited but 

uncrystallized snow of lower albedo (Swithinbank and Lucchitta, 1986). 

14 
Fletchefl lee Rise 

0 20 KILOMETERS 

Figure 8. Morphological features in Sentinel Range in Ellsworth Mountains and Rutford Ice Stream. Composite 

of bands 4, 5, and 7 of Landsat 1 MSS image 1560-11492, 3 February 1974. Image -is digitally enhanced to bring 

out detail in snow and ice; however, detail of rock outcrops is suppressed by this method. Note double ridge 

(arrows) along crest line of Fletcher Ice Rise. Grounding line of Rutford Ice Stream (dots) after Stephenson and 

Doake (1982). Ice stream flows from left to right. Note contrast between its sliding part (left of grounding 

line), which displays linear flow markings, and its floating part (right of grounding line), which displays linear and 

transverse markings. D, sinuous depressions formed where floating ice stream slides over suspected shoal; V, 

buried valleys upstream from glacier entering Rutford Ice Stream from west; S, scarps in buried mountain ranges 

visible through ice cover. 

15 
0 20 KILOMETERS 

R 

~ 

R 

Figure 9. Morphological features in Theron Mountains and Slessor Glacier. Digitally enhanced composite of 

bands 4, 5, and 7 of Landsat 1 MSS image 1548-07145, 22 January 1974. Glacier flows southwest. Note 

influence of subglacial morphology and structure on surface of glacier and ice sheet to its left. S, linear scarps 

along Theron Mountains and across Slessor Glacier; may be expressions of subglacial fault lines. R, ridges in ice 

and associated extensive crevasse fields; probably mark bedrock obstacles in flow path. V, valleys in Theron 

Mountains visible in spite of ice cover. Light and dark mottling at bottom right and top left caused by clouds. 

16 
aerial photographs with Landsat images, MacDonald 

noted that the margin of the Ronne Ice Shelf had 

advanced 16 km between January 1966 and February 

1973; however, this measurement may have been in 

error because of inaccuracies in the map. Ferrigno 

and others (1983) determined the velocity of the Pine 

Island Glacier, a tidal-outlet glacier on the West 

Antarctic coast: During the 750-day interval 

represented by repetitive Landsat images, the 

terminus moved about 4.5 km, at an average velocity 

of 6 m per day. This glacier is a large ice stream 

draining the ice sheet of West Antarctica. It is 

presently surging, apparently having punched through a 

confined and pinned ice shelf (Hughes, 1981; Stuiver 

and others, 1981). Such surges can have profound 

effects on the mass balance of the ice sheets, and 

their periodic monitoring is essential. 

Our studies show that the Ferrar Glacier of 

southern Victoria Land retreated 3 km between 1957 

and 1983, an average of 110 meters/year. This 

assessment is based on Landsat images taken in 1975 

and conventional photographs taken in 1957 and 1983. 

Landsat images of the Byrd Glacier, also in southern 

Victoria Land, taken in January 1974 and November 

1983 depict a large crevasse where the glacier enters 

the Ross Ice Shelf (fig. 10). This shear-rupture 

crevasse (Hughes, 1983) opened 700 m in the 10 years 

between the acquisition of the two images. Hughes 

(1983) pointed out that the study of crevasses in ice 

shelves is important because crevasses serve as focal 

points for ice-shelf disintegration. The floating part 

of Byrd Glacier moved about 8.0 km in this 10-year 

interval, or an average of 800 meters/year, as 

determined by transverse depressions that maintained 

their identity in the glacier (fig. 10). Our rate agrees 

with rates measured on the ground by Swithinbank 

(1963), Hughes (1977), Hughes and Fastook (1981), and 

Brecher (1982). 

Considerable changes have been observed along 

Antarctic coastlines, and their documentation 

significantly helps both in the interpretation of the 

dynamics and mass balance of ice sheets and ice 

shelves and in the forecasts of anticipated changes. 

The monitoring is especially important for the ice 

sheet of West Antarctica, which overlies a bedrock 

surface of considerable relief (including many 

volcanoes); 70 percent of this surface is below sea 

level (Znachko-Yavorskiy, 1978). The condition of the 

ice sheet is there fore thought to be inherently unstable 

(Hughes, 1973; Weertman, 1974). Increased calving of 

ice fronts on the shelves might cause surging of ice 

streams, a negative mass balance of the ice sheet, 

retreat of the grourx:ling line, and rapid disintegration 

of the ice sheet (Stuiver arx:I others, 1981). Disintegration of the ice sheet of West Antarctica may lead to a 

significant rise in sea level, as much as 3.5 m, along 

the coastlines of the world according to Hoffman and 

others (1983). Monitoring the coastline region arx:l ice 

shelves of Antarctica is clearly an important task 

(Williams, 1985). Because most Larx:lsat images of 

Antarctica were acquired in the early to mid-1970's, 

data representing a 10-year time lapse are already 

available for comparative analysis. 

SPECTRAL AND STRUCTURAL STUDIES 

Outcrop areas in Antarctica are small: only 2.4 

percent of Antarctica is free of ice (Drewry and 

others, 1982). Because most of the bedrock crops out 

in small nunataks, the Landsat MSS images, which have 

a resolution of about 80 meters/pixel, are not well 

suited to the analysis of rocks by spectral methods. 

However, some preliminary research on 5pectral 

analysis of Landsat MSS images of the Dry Valleys 

area of Antarctica and correlation with field samples 

has been achieved by C. S. Southworth of the USGS 

(Ferrigno and others, 1983). The 30-meter/pixel 

resolution of thematic mapper (TM) images of Landsat 

5 will probably be adequate for 5pec tral studies. 

As with Landsat images of other areas on Earth, 

some images of Antarctica show distinct structural 

trends that, when combined with other types of 

geological studies, aid in geological interpretation. In 

5pite of the ice cover, the structural orientation can 

be seen clearly in some mountainous regions (fig. 9). 

To our knowledge, only one extensive study of 

structural features in Antarctica based on Larx:Isat 

data has been completed (Rivereau, 1978). Our 

enhanced multi5pectral images of Antarctica (figs. 8 

and 9) show many linear features. A con5picuous 

lineament signaling a probable structural discontinuity 

of unknown origin shows clearly on figure 11. Such 

images will prove useful in future geological or 

structural analyses. 

CONCLUSIONS 

Digitally enhanced Landsat MSS images are a 

significant improvement over the commonly used 

black-and-white paper prints of MSS band 7. They 

show considerably more detail in surficial morphology 

and shed light on many Antarctic scientific problems. 

Our studies show that the images are particularly 

helpful for the preparation of accurate color 

planimetric maps, which may serve as base materials 

for the superposition and correlation of other types of 

geological data. Thematic maps that show, for 

instance, only rock or only ice areas depict the 

location of desired features with a minimum of 

effort. Blue-ice areas, important in the search for 

Antarctic meteorites, are easily located on the 

multispectral images. The synoptic view of the images 

and mosaics provides several kirx:ls of data: 

information on the flow lines associated with ice 

streams; the location of ice rises, ice rumples, and 

other possible grounded areas; and the extent and 

structural orientation of some buried mountain 

ranges. Monitoring the coastline for changes with 

time may indicate waxing or waning of the ice sheets; 

such changes may have far-reaching implications for 

variations in world climate. Overall, multi5pectral 

digital Landsat images are extremely helpful in 

Antarctic research, and we hope that inc rea sed use of 

them in the future will significantly aid in the 

exploration of that continent. 

17 
0 20 KILOMETERS 

I I Figure 10. Enhanced image of Byrd Glacier regwn. Excerpt of composite of bands 4, 5, and 7 of Landsat 4 MSS 

image 40495-18544, 23 November 1983. Compare this image with those of figure 5, acquired almost 10 years 

earlier. In 10 years, crevasse (C) moved about 1.5 km toward ice shelf (top of picture) and opened 700 m; 

transverse ridges (T) on glacier moved about 800 m. Note break in density of flow lines at F; this change, so far 

unexplained, has not moved in 10-year interval. Also note cirquelike bedrock sill (S) over which glacier spills 

where entering mountains. 

18 
0 20 KILOMETERS 

Figure 11. Sinusoidally stretched image of McMurdo Sound region and Dry Valleys. False-color multispectral 

composite of bands 4. 5~ and 7 of Landsat 2 MSS image 2279-19361. 28 October 1975. In sinusoidal stretching. 

DN (digital number) values of dark and light areas were separately stretched over entire gray scale (Chavez and 

others~ 1977). Light areas of original image (snow and ice scenes) are stretched in an inverse direction. giving a 

negative rendition. This method preserves maximum detail in both original light and dark areas, but colors are 

unrealistic. Note conspicuous lineation between arrows. probably reflecting a structure. Ross Island at top 

right, McMurdo Station at tip of fingerlike peninsula extending southwestward from Ross Island. Dry Valleys are 

in center of image; within them. Lake Yanda shows as brilliant blue. Snow is brown, ice is greenish blue, and 

shadows are black or dark blue. 

19 
REFERENCES CITED 

Armstrong, Terrence, Roberts, Brian, and Swithinbank, 

Charles, 1973, illustrated glossary of snow and 

ice: Cambridge, England, Scott Polar Research 

Institute, 60 p. 

Arvidson, R.E., and Guinness, E.A., 1981, Integration 

of remote sensing, geophysical, and geological 

data sets to better understand the structural 

geology of the St. Francois Mountains, southeast 

Missouri and surrounding areas, in Carver, R.R., 

ed., 1981, International geoscience and remote 

sensing symposium digest: New York, Institute 

of Electrical and Electronic Engineers, p. 895-

896. 

Behrendt, J.C., 1983, Are there petroleum resources in 

Antarctica?, in Behrendt, J.C., ed., Petroleum 

and mineral resources of Antarctica: 

U.S. Geological Survey Circular 909, p. 3-2.4. 

Bentley, C. R., and Giovinetto, M. B., 196 2., Ice -flow 

studies on the ice dome of Roosevelt Island, 

Antarctica: Transactions, American Geophysical 

Union, v. 43, no. 3, p. 369-372.. 

Brecher, H.H., 1982., Photogrammetric determination 

of surface velocities and elevations on Byrd 

Glacier: Antarctic Journal of the United States, 

v. 17, no. 5, p. 79-81. 

Budd, W.F., 1969, The dynamics of ice masses: 

Australian National Antarctic Research 

Expeditions, Scientific Reports, Series A (IV) 

(Glaciology), Publication No. 108, 2.16 p. 

Bull, Colin, and Lipschutz, M. E., 1982., Workshop on 

Antarctic glaciology and meteorites: Lunar and 

Planetary Institute Technical Report 82.-03, 57 p. 

Cassidy, W.A., 1979, Antarctic meteorites: Eos, 

Transactions, American Geophysical Union, v. 

60, no. 13, p. 175-177. 

Chavez, P.S., Jr., 1975, Atmospheric, solar and M.T.F. 

corrections for ERTS digital imagery [abs.], in 

American Society of Photogrammetry 

Symposium, Phoenix, 197 5, Proceedings: Falls 

Church, Va., p. 69-69a. 

Chavez, P.S., Jr., and Berlin, G.L., 1984, Digital 

processing of SPOT simulator and Landsat TM 

data for the SP Mountain region, Arizona, in 

SPOT Simulator Applications Handbook: 1984 

SPOT Symposium, Scottsdale, Ariz., May 2.0-2.3, 

1984, Proceedings, p. 56-66. 

Chavez, P.S., Jr., Berlin, G.L., and Mitchell, W.B., 

1977, Computer enhancement techniques of 

Landsat MSS digital images for land use/land 

cover assessment, in Remote sensing of Earth 

resources, v. 6: Remote Sensing of Earth 

Resources, 6th Annual Conference, Tullahoma, 

Tenn., March 2.9-31, 1977, Proceedings of 

Technical Papers, p. 2.59-2.7 5. 

Clapp, J.L., 1965, Summary and discussion of survey 

control for ice flow studies on Roosevelt Island, 

Antarctica: University of Wisconsin, Madison, 

Geophysical and Polar Research Center, Report 

65-1, 98 p. 

Condit, C.D., and Chavez, P.S., Jr., 1979, Basic 

concepts of computerized digital image 

processing for geologists: U.S. Geological Survey 

Bulletin 1462., 16 p. 

20 

Cutts, J.A., and Blasius, K.R., 1981, Origin of Martian 

out flow channels--The eolian hypothesis: Journal 

of Geophysical Research, v. 863, no. 6, p. 507 5-

5102.. 

Dowdeswell, J .A., and Mcintyre, N.F., 1986, The 

saturation of Landsat MSS detectors over large 

ice masses: International Journal of Remote 

Sensing, v. 7, no. 1, p. 151-164. 

Drewry, D.J., Jordan, S.R., Jankowski, E., 1982., 

Measured properties of the Antarctic ice sheet--

Surface configuration, ice thickness, volume and 

bedrock characteristics: Annals of Glaciology, v. 

3, p. 83-91. 

Ferrigno, J .G., and Williams, R.S., Jr., 1983, 

Limitation in the use of Landsat images for 

mapping and other purposes in snow- and icecovered regions: Antarctica, Iceland and Cape 

Cod, Massachusetts, in International Symposium 

on Remote Sensing- of Environment, 17th, 

Proceedings: Ann Arbor, Environmental 

Research Institute of Michigan, v. 1, p. 335-355. 

Ferrigno, J.G., Williams, R.S., Jr., Southworth, C.S., 

and Meunier, T.K., 1983, Glaciological and 

geological studies of Antarctica with satellite 

remote sensing technology [abs.], in U.S. 

Geological Survey Polar Research Symposium--

Abstracts with Program, Washington, D.C., Oct. 

12.-14, 1983: U.S. Geological Survey Circular 911, 

p. 2.0-2.1. 

Hoffman, LS., Keyes, Dale, and Titus, J.G., 1983, 

Projecting future sea level rise. Methodology, 

estimates to the year 2.100, and research needs--

A report of the Strategic Studies Staff, Office of 

Policy Analysis, Office of Policy and Resource 

Management, U.S. Environmental Protection 

Agency: Washington, D.C., 2nd revised edition, 

12.1 p. 

Hughes, T.J., 1973, Is the West Antarctic ice sheet 

disintegrating?: Journal of Geophysical 

Research, v. 78, no. 33, p. 7884-7910. 

1977, West Antarctic ice streams: Reviews of 

---Geophysics and Space Physics, v. 15, no. 1, p. 1-

46. 

1981, The weak underbelly of the West Antarctic 

---ice sheet: Journal of Glaciology, v. 2.7, no. 97, p. 

518-52.5. 

1983, On the disintegration of ice shelves--The 

---role of fracture: Journal of Glaciology, v. 29, no. 

101, p. 98-117. 

Hughes, T.J., and Fastook, J.L., 1981, Byrd Glacier--

197 8-1979 field results: Antarctic Journal of the 

United States, v. 16, no. 5, p. 86-89. 

MacDonald, W.R., 1976a, Antarctic cartography, in 

Williams, R.S., Jr., and Carter, W.D., ed~ 

ERTS-1, a new window in our planet: U.S. 

Geological Survey Professional Paper 92.9, p. 37-

43. 

1976b, Glaciology in Antarctica, in Williams, 

---R.S., Jr., and Carter, W.D., eds., ERTS-1, a new 

window in our planet: U.S. Geological Survey 

Professional Paper 929, p. 194-195. 

Marsh, P.D., 1985, Ice surface and bedrock topography 

in Coats Land and part of Drenning Maud Land, 

Antarctica, from satellite imagery: British 

Antarctic Survey Bulletin, no. 68, p. 19-36. 
Mart in, P .J ., 197 6, Ridges on Ant arctic ice rises: 

Journal of Glaciology, v. 17, no. 7 5, p. 141-144. 

Martin, P.J., and Sanderson, T.J.O., 1980, Morphology 

and dynamics of ice rises: Journal of Glaciology, 

v. 25, no. 91, p. 33-45. 

Marvin, U.B., 1982, Meteorite placer deposits of 

Antarctica: Episodes, v. 1982, no. 3, p. 10-15. 

Meunier, T.K., 1983, The use of satellite technology in 

the search for meteorites in Antarctica [abs.], in 

U.S. Geological Survey Polar Research 

Symposium--Abstracts with Program, 

Washington, D.C., Oct. 12-14, 1983: U.S. 

Geological Survey Circular 911, p. 19-20. 

National Science Foundation, 1981, Antarctic 

meteorites provide new data: Antarctic Journal 

of the United States, v. 16, no. 2, p. 1-4. 

Nye, J.F., 1959, The motion of ice sheets and glaciers: 

Journal of Glaciology, v. 3, no. 26, p. 493-507. 

<l>degaard, Helge, and Helle, S.G., 198 2, Polar mapping 

using Landsat data--Svalbard and Dronning Maud 

Land: Oslo, Norway, International Business 

Machines and Norsk Polarinstitutt, Final Report, 

66 p. 

Olsen, E.J., 1981, Estimates of total quantity of 

meteorites in the east Antarctica ice cap: 

Nature, v. 292, no. 5823, p. 516-518. 

Orheim, Olav, 1978, Glaciological studies by Landsat 

imagery of perimeter of Dronning Maud Land, 

Antarctica: Oslo, Norway, Norsk Polarinstitutt, 

Skrifter, no. 169, p. 69-80. 

Paterson, W.S.B., 1981, The physics of glaciers (2d 

ed.): Oxford, Pergamon Press, 380 p. 

Rivereau, J.C., 1978, Morphostructural outline of the 

Antarctic: Inventory of lineaments and 

outcropping areas from Landsat 1 and 2 imagery: 

Rueil-Malmaison, Bureau d'Etudes Ind.ustrielles 

et de Coop~ration de !'Institute Francais du 

P~trole (BEICIP). 

Southard, R.B., and MacDonald, W.R., 1974, The 

cartographic and scientific application of ERTS1 imagery in polar regions: U.S. Geological 

Survey Journal of Research, v. 2, no. 4, p. 385-

394. 

Stephenson, S.N., and Doake, C.S.M., 1982, Dynamic 

behaviour of Rutford Ice Stream: Annals of 

Glaciology, v. 3, p. 295-299. 

Stuiver, Minzo, Denton, G.H., Hughes, T.J., and 

Fastook, J.L., 1981, History of the marine ice 

sheet in West Antarctica during the last 

glaciation: A working hypothesis, in Denton, 

G.H., and Hughes, T.J., eds., The last great ice 

sheets: New York, John Wiley and Sons, 

p. 319-436. 

Swithinbank, C.W.M., 1963, Ice movement of valley 

glaciers flowing into Ross Ice Shelf, Antarctica: 

Science, v. 141, no. 3579, p. 523-524. 

Swithinbank, C.W.M., and Lucchitta, B.K., 1986, 

Multispectral digital-image mapping of Antarctic 

ice features: Annals of Glaciology, v. 8, p. 159-

163. 

Trautwein, C.M., contributing author, 1983, Combined 

data sets: Geological applications, chapter 3 in 

Colwell, R.N., ed., Manual of remote sensing (2d 

ed.): Falls Church, Va., American Society of 

Photogrammetry, v. 2, p. 17 57-1762. 

Weertman, Johannes, 1974, Stability of the junction of 

an ice sheet and an ice shelf: Journal of 

Glaciology, v. 13, no. 67, p. 3-11. 

Whillans, LM., and Cassidy, W.A., 1982, Glaciologic 

notes on the Allan Hills area [abs.], in Bull, Colin, 

and Lipschutz, M.E., Workshop on Antarctic 

glaciology and meteorites: Lunar and Planetary 

Institute Technical Report 82-03, p. 51. 

1983, Catch a falling star--meteorites and old 

---ice: Science, v. 222, no. 4619, p. 55-57. 

Williams, R.S., Jr., 1985, Monitoring the area and 

volume of ice caps and ice sheets: Present and 

future opportunites using satellite remotesensing technology, in Committee on Glaciology, 

Polar Research Board, Glaciers, ice sheets, and 

sea level--Effects of a co2-induced climate 

change: Washington, D.C., National Academy 

Press, p. 23 2-240. 

Williams, R.S., Jr., Ferrigno, J.G., and Kent, T.M., 

1984, Index map and table of optimum Landsat 1, 

2, and 3 images of Antarctica: U.S. Geological 

Survey Open-file Report 84-573, 2 sheets 

(1:5,000,000-scale map). 

Williams, R.S., Jr., Ferrigno, J.G., Kent, T.M., and 

Schoonmaker, J.R., Jr., 1982, Landsat images 

and mosaics of Antarctica for mapping and 

glaciological studies: Annals of Glaciology, v. 3, 

p. 321-326. 

Williams, R.S., Jr., Meunier, T.K., and Ferrigno, J.G., 

1983, Blue ice, meteorites, and satellite imagery 

in Antarctica: The Polar Record, v. 21, no. 134, 

p. 493-496. 

Znachko-Yavorskiy, G.A., 1978, The topography of 

Antarctica: Polar Geography, v. 2, no. 1, p. 1-13. 

21