Of all the world?s continents Antarctica is the coldest, the highest, and the least
known. It is one and a half times the size of the United States, and on it lies 91 percent
(30,109,800 km3) of the estimated volume of all the ice on Earth. Because so little is
known about Antarctic glaciers compared with what is known about glaciers in populated
countries, satellite imagery represents a great leap forward in the provision of basic
data. From the coast of Antarctica to about 81?south latitude, there are 2,514 Landsat
nominal scene centers (the fixed geographic position of the intersection of orbital paths
and latitudinal rows). If there were cloud-free images for all these geographic centers,
only about 520 Landsat images would be needed to provide complete coverage. Because
of cloud cover, however, only about 70 percent of the Landsat imaging area, or 55 percent
of the continent, is covered by good quality Landsat images. To date, only about 20
percent of Antarctica has been mapped at scales of 1:250,000 or larger, but these maps
do include about half of the coastline. The area of Antarctica that could be planimetrically
mapped at a scale of 1:250,000 would be tripled if the available Landsat images
were used in image map production.
This chapter contains brief descriptions and interpretations of features seen in 62
carefully selected Landsat images or image mosaics. Images were chosen on the basis of
quality and interest; for this reason they are far from evenly spaced around the continent.
Space limitations allow less than 15 percent of the Landsat imaging area of Antarctica
to be shown in the illustrations reproduced in this chapter. Unfortunately, a wealth
of glaciological and other features of compelling interest is present in the many hundreds
of images that could not be included. To help show some important features beyond the
limit of Landsat coverage, and as an aid to the interpretation of certain features seen in
the images, 38 oblique aerial photographs have been included. Again, these represent
only a small fraction of the large number of aerial photographs now available in various
national collections.
The chapter is divided into five geographic sections. The first is the Transantarctic
Mountains in the Ross Sea area. Some very large outlet glaciers flow from the East
Antarctic ice sheet through the Transantarctic Mountains to the Ross Ice Shelf. Byrd
Glacier, one of the largest in the world, drains an area of more than 1,000,000 km2. Next,
images from the Indian Ocean sector are discussed. These include the Lambert Glacier-
Amery Ice Shelf system, so large that about 25 images must be mosaicked to cover its
complex system of tributary glaciers. Shirase Glacier, a tidal outlet glacier in the sector,
flows at a speed of 2.5 km a-l. About 200 km inland and 200 km west of Shirase Glacier
lie the Queen Fabiola (?Yamato?) Mountains, whose extensive exposures of `blue ice? lay
claim to being the world?s most important meteorite-collecting locality, with more than
4,700 meteorite fragments discovered since 1969.
The Atlantic Ocean sector is fringed by ice shelves into which flow large ice streams
like Jutulstraumen, Stancomb-Wills, Slessor, and Recovery Glaciers. Filchner and
Ronne Ice Shelves together cover an area two-thirds the size of Texas. From the western
margin of the Ronne Ice Shelf, the north-trending arc of the Antarctic Peninsula, with
its fjord and alpine landscape and fringing ice shelves, stretches towards South America.
The Pacific Ocean sector begins with the Ellsworth Mountains, which include the highest
peaks (Vinson Massif at 4,897 m) in Antarctica. The area between the Ellsworth Mountains
and the eastern margin of the Ross Ice Shelf is fringed with small ice shelves and
some major outlet glaciers. One of these, Pine Island Glacier, was found from comparing
1973 and 1975 images to have an average ice-front velocity of 2.4 km a-l. This part of
Antarctica