Encyclopedia Britannica 1963 [02].pdf

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THE
UNIVERSITY
O F CHICAGO
The Encyclopadia Britnnnicn
ir
published with the editorinl ndvice ofthe faculties
of The University of Chicngo nnd of
n
committee of men2
beys
of
the fnczllties
of
Oxford, Cnnzbridge
and London uni~ersities of n committee
and
nt The Uniuersity of Toronto
"
L
ET
K N O W L E D G E G R O W FROM MORE T O M O R E
A
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B
E
H
U
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A
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HED
."
Volume
2
A
NTARCTICA
TO
B
ALFE
ENCYCLOPEDIA BRITANNICA, INC.
W I L L I A M BENTOi\T,
PUBLISHER
GENEVA
SYDNEY
CHICAGO. 1,ONDON. TORONTO
PRINTED IN
THE
U.
S.
A.
Volume
2
A
NTARCTICA,
the continent lying concentrically about Pacific: Atlantic and Indian oceans; it is notoriously t h e stormiest
in the world, for there is nothing to break the force of t h e persistent
west winds. TVarmer tropical waters meet with cold antarctic
waters in a remarkably permanent girdling line ranging between
latitude
43'"
and
65'
S.
known as the Antarctic convergence. T h i s
line. which varies considerably xvith longitude but generally within
and not more than a degree or two of latitude per year? establishes
a boundary b e t r e e n subtemperate and subantarctic zones. South
of the convergence the waters a r e characteristically ice-laden a n d
abound ~ v i t h
subpolar aquatic liie. I t is a feeding region for m y r-
iads of pelagic sea birds and is the location of Antarctica's principal
industry- whaling.
T h e continent itself is essentially circular in f o r m except for
the Grah,am-Palmer peninsula and the inward bights of t h e Ross
and TVeddell seas. T h e great mile-thick layer of continental ice
thins toward the coasts and discharges flat-topped icebergs into t h e
surrounding seas from piedmont glaciers, ice tongues and shelf-ice
systems
(see
also
G
L
A
C
IER
).
Along the periphery of the continent
are rugged mountain peaks left bare by the skirting a n d receding
b
ice. Farther inland the rugged landscape is generally d r o ~ v n e d y
ice col-er. although gentle rolling surfaces and crevassed regions
in places reflect its hidden character.
T h e continent is asymetrically divided into two p a r t s b y a high
upthrusted mountain range exceeding 15.000 i t . elevation. T h i s
antarctic cordillera runs from \.'ictoria Land on t h e N e w Zealand
side toward Coats Land on the Atlantic side. I t s central relation-
ship xvith the .%ndean type ranges of the Graham-Palmer peninsula
is still uncertain f o r lack of adequate exploration. T h e geological
formations of this central range seem to bear little resemblance t o
the Andean type. however. and its flat-lying, uplifted sedimentary
rocks are in part carboniferous. Extensive
lo^^
quality bituminous
coal outcrops to within 200-300 mi. of the south pole yield fossils
which portray an earlier age when the continent was once forested.
\Vhether this former lvarmer climate was due to climatic change,
polar ~vanderingor continental d r i f t is still a m a t t e r of intensive
conjecture and investigation.
\Vest Antarctica, the lesser of the two major subdivisions of t h e
continent. lies almost entirely within the western hemisphere!
facing toward the Pacific ocean. I c e soundings h a v e s h o x ~ nthis
region to be largely a n ice-covered archipelago. I c e thickness be-
the geographic south pole. Antarctica increases in
importance as it becomes better known, and i t is
also significant as a n area of large-scale international
co-operation.
This article is divided into the following sections:
I.
General Survey
1. Location and Description
2 .
Knowledge of the Region
3.
Ownership
11.
Physical Characteristics
1. lhleteorology
2 .
Geology
3 ,
Antarctic Ocean
4. .Animal Life
5 .
Plant Life
111.
Exploration and Discovery
1.
Conjecture About Antarctica
2. Crossing the Antarctic Circle
3.
Discovery of the Mainland (1820-99)
4.
Quest for the South Pole
5 .
Exploration, 1920-40
IV.
Sational Efforts at Occupation (1943-55)
1. Conflicting Claims
2. Operation "Highjump" and Other
U.S.
Expeditions
3.
A.X.;\.R.E.
4. Other Events
\'.
International Co-operation
1. International Geophysical Year
2 .
Special Committee for Antarctic Research
'
3.
Antarctic Treaty
4. Future Prospects for Antarctica
I.
GENERAL
SURVEY
1.
L o c a t i o n and Description.- Antarctica lies in unique iso-
lation in the triangle formed by the southernmost extension of
South America. Africa and Australia. The nearest oceanic ap-
proach to a neighbouring continent is about 600 mi across Drake
straits from Tierra del Fuego to the tip of the Graham-Palmer
peninsula. (Because of disputes over priority of discovery the
British call this peninsula Graham Land and Americans call it
Palmer peninsula; the hyphenated form used in this article recog-
nize> the d ~ s p u t e . Argentma calls it San Jldrtin and Chile Tierra
de O'Higgins
)
Surrounding the continent is the Antarctic (or
Southern) ocean. which is merely the confluent portions of the

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