Coastal-Change and Glaciological Maps of Antarctica

Changes in the area and volume of the 

two polar ice sheets in Antarctica (fig. 1) and 

Greenland are intricately linked to changes in 

global climate, and could result in sea-level 

changes that could severely affect the densely 

populated coastal regions on Earth. Melting 

of the West Antarctica part of the Antarctic 

ice sheet alone could cause a sea-level rise 

of approximately 6 meters (m). The potential sea-level rise after melting of the entire 

Antarctic ice sheet is estimated to be about 

73 m. In spite of its importance, the mass 

balance (the net volumetric gain or loss) of 

the Antarctic ice sheet is poorly known; it is 

not known whether the ice sheet is growing 

or shrinking. As a result, measurement of 

changes in the Antarctic ice sheet has been 

given a very high priority in recommendations 

by the Polar Research Board of the National 

Research Council, by the Scientific Committee on Antarctic Research (SCAR), and by the 

National Science Foundation’s Office of Polar 

Programs. 

An extensive archive of early 1970s 

Landsat 1, 2, and 3 Multispectral Scanner 

(MSS) images of Antarctica was the impetus for the U.S. Geological Survey (USGS), 

in cooperation with Scott Polar Research 

Institute (Cambridge, U.K.), to carry out a 

comprehensive analysis of the glaciological 

features of the coastal regions of Antarctica. 

The project was later modified to include 

analysis of coastal change using Landsat 4 and 

5 MSS and Thematic Mapper (TM) images 

from the late 1980s/early 1990s, declassified 1963 Argon (Corona Program) images, 

1992 and 1995 European Space Agency 

(ESA) Remote Sensing Satellite (ERS) 

radar images, 9 September–2 October 1997 

RADARSAT images, Landsat 7 Enhanced 

Thematic Mapper (ETM+) images (April 

1999–May 2003), and Moderate Resolution 

Imaging Spectroradiometer (MODIS) images 

(post-mid-December 1999). The different data 

sets allow determination of coastal change 

in Antarctica for >30 years where suitable 

images exist. Coastal change has been most 

pronounced on the Antarctic Peninsula in the 

last few decades, where the Wordie Ice Shelf 

has practically disappeared, the northern part 

of the Larsen Ice Shelf has disintegrated, and 

other ice shelves are also changing. Cooperation with other Antarctic mapping groups now 

includes scientists from Italy, Russia, Norway, 

Canada. Australia, Argentina, and Germany. 

The coastal-change and glaciological mapping task, an element of the Glacier Studies 

Project, has several objectives:

•	 Determine coastline changes in Antarctica that have occurred at three or more 

time intervals between the mid-1970s 

and the latest available images.

•	 Establish an accurate base-line series

of 1:1,000,000-scale maps (in printed 

and/or digital format) (fig. 2) that 

defines, from the analysis of remotely 

sensed data, the glaciological characteristics of the coastline of Antarctica, 

for example, floating ice (ice fronts) 

and grounded ice (ice walls), and the 

location of floating ice fronts during the 

time periods represented by the imagery.

•	 Determine glacier-ice velocities of

selective outlet glaciers, ice streams, 

and ice shelves in some coastal regions.

•	 Compile an inventory of named (from

published maps and gazetteers) and 

unnamed (from analysis of Landsat and 

other images) outlet glaciers and ice 

streams in Antarctica.

•	 Publish the results of the analyses as

Coastal-Change and Glaciological Maps 

of Antarctica (I–2600), of the USGS 

Geologic Investigations Series (I–Maps) 

(fig. 2). Most 1:1,000,000-scale maps 

extend to the southernmost nunatak 

within each map area or to the southernmost extent of Landsat images (about 

81.5°S. lat.), although for some ice 

shelves, RADARSAT or MODIS images 

were used to extend maps further south. 

The 1:1,000,000-scale maps will be 

combined to produce a 1:5,000,000-

scale map of Antarctica (in both printed 

and digital formats).

Ice fronts, iceberg tongues, and glacier 

tongues are the most dynamic and changeable 

features in the coastal regions of Antarctica. 

Floating ice margins are subject to frequent 

and large calving events or rapid flow. These 

situations lead to annual and decadal changes 

in the position of ice fronts on the order of 

90E

0E

180W

60S

90W

W 0 E

W 180 E

60S

80S Ronne

 Ice 

Shelf

Cook Ice Shelf

Lazarev 

Ice Shelf

Filchner 

Ice Shelf

Larsen

Ice Shelf

Voyeykov

Ice Shelf

Shackleton

Ice Shelf

Ross

Ice Shelf

Amery 

Ice Shelf

West

Ice Shelf

Sulzberger

Ice Shelf

Getz

Ice Shelf

Abbot

Ice Shelf

George VI

Ice Shelf

EAST

ANTARCTICA

WEST 

ANTARCTICA

Weddell 

 Sea

Brunt 

Ice Shelf

Fimbul Ice

Shelf Rilser-Larsen

Ice Shelf

0 1000 KILOMETERS

Figure 1. Index map to the principal geographic features of Antarctica, including 

the ice shelves where large coastal-change 

events commonly occur.

1000 KILOMETERS

90E

0

0E

180W

60S

90W

W 0 E

W 180 E

60S

80S

A

B C

E

F

G

H I

J

K

L

M

N

O

P

Q

R S

T V U

W

D

Figure 2. Index map showing the locations and names of the published and planned 1:1,000,000-

scale coastal-change and glaciological maps of Antarctica. The dates (2004) of published maps 

are shown that are available in print and digital formats [http://pubs.usgs.gov/imap/2600/]. 

Published (Date of Publication) and Planned 

USGS I–2600 Maps:

A-Trinity Peninsula (2006) 

B-Larsen Ice Shelf (2008)

C-Palmer Land (2009)

D-Ronne Ice Shelf (2005)

E-Eights Coast (2004)

F-Bakutis Coast (2005)

G-Saunders Coast (2003)

H-Ross Ice Shelf (2008)

I-Ross Island (2010)

J-Drygalski Ice Tongue*

K-Oates Coast*

L-George V Coast*

M-Banzare Coast*

N-Budd Coast*

O-Queen Mary Coast*

P-West Ice Shelf*

Q-Amery Ice Shelf*

R-Mawson Coast*

S-Prince Olav Coast*

T-Princess Ragnhild Coast*

U-Fimbul Ice Shelf*

V-Cape Norvegia*

W-Filchner Ice Shelf-Coats 

 Land* 

X-Antarctica

U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet FS 2005–3055

(Supersedes FS–50–98)

Revised September 2011
several kilometers, even tens of kilometers in 

extreme cases of major calving events (fig. 3). 

On the coastal-change and glaciological maps, the positions of the dynamic ice 

fronts as observed on remotely sensed data 

have been mapped and annotated with the 

exact date of each position. This record 

makes it possible to analyze changes that 

have occurred. Although calving does occur 

along ice walls, the magnitude of the change 

on an annual to decadal basis is generally not 

discernible on the images; therefore, ice walls 

can be used as relatively stable reference features against which to measure other changes 

along the coast. Only a single observation date 

is given for the position of ice walls.

Velocities of floating glaciers (such as 

glacier tongues, ice streams, ice shelves) are 

determined by three methods. (1) An interactive one in which crevasse patterns are traced 

visually on images. (2) An auto-correlation 

program developed by the U.S. National 

Aeronautics and Space Administration 

(NASA). The larger glacier tongues and ice 

shelves have well-developed rift patterns that 

can be used for velocity measurements. Under 

optimum conditions, errors can be as small as 

±0.02 km per year (a–1), but for most Landsat 

image pairs, where registration of features is 

not as accurate, the accuracy of velocity vectors is ±0.1 km a–1. (3) Ice-surface velocities 

can be determined from satellite radar interferometry, a technique developed by scientists 

at the California Institute of Technology (Jet 

Propulsion Laboratory) and NASA.

Producing a sophisticated glacier inventory 

of Antarctica according to the requirements 

of the World Glacier Monitoring Service, as 

part of its ongoing “World Glacier Inventory” 

program, is difficult to accomplish with the 

present state of glaciological knowledge about 

Antarctica. Landsat and other images and 

available maps are used in the compilation 

of the coastal-change and glaciological maps 

to produce a reasonably complete preliminary inventory of named and unnamed outlet 

glaciers and ice streams and also to define, 

more accurately, related glaciological features 

such as ice domes, ice piedmonts, ice shelves, 

ice rises, ice rumples, glacier tongues, iceberg 

tongues, etc.

The Coastal-Change and Glaciological 

Maps of Antarctica are being produced as 

Task 2 of the Glacier Studies Project [http://

www.glaciers.er.usgs.gov] of the U.S. Geological Survey Geology Disciplines’ Earth 

Surface Dynamics Program, a component of 

13 interagency Federal U.S. Climate Change 

Science Program, of which the U.S. Department of the Interior is a member. 

Figure 3. Left, Landsat MSS image of margin of the Filchner Ice Shelf, Weddell Sea, West Antarctica, on 11 November 1973. Right, Landsat image of 

the same area on 18 October 1986 after a major calving event.

For more information, please contact:

Dr. Richard S. Williams, Jr. 

U.S. Geological Survey

Woods Hole Coastal and Marine 

 Science Center 

384 Woods Hole Road 

Woods Hole, MA 02543-1598 

Tel: 508-540-6405 

e-mail: geoinfo@comcast.net

 

Jane G. Ferrigno

U.S. Geological Survey

926A National Center

12201 Sunrise Valley Drive

Reston, VA 20192-0002

Tel: 703-648-6360

e-mail: jferrign@usgs.gov

Kevin M. Foley

U.S. Geological Survey

926A National Center

12201 Sunrise Valley Drive

Reston, VA 20192-0002

Tel: 703-648-5285

e-mail: kfoley@usgs.gov