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MMER AND AUTUMN 1957. VOL. V, NOS 3 AN

D 4

EDITOR: JAN HAHN

Published quarterly and distributed to the Asso-
ciates of the Woods Hole Oceanographic
Institution and others interested
in Oceanography

Woods Hole Oceanographic Institution

WOODS HOLE. MASSACHUSETTS

HENRY B. BIGELOW
Chairman of the TSoard of Truittes

RAYMOND STEVENS
"President of the Corporarion

COLUMBUS O'D. ISELIN
'Director

BOSTWICK H. KETCHUM
Senior Oceanographer

MEN, EARTH AND INSTRUMENTS

E have heard so much Sputnik lately and so much talk
about rockets and space flight, as topics in themselves, that it
appears as if the object of the IGY: the study of the earth and its
atmosphere, seems to have been forgotten.

Our cover may help to serve as a reminder that the success of
the IGY depends upon men. Men who make the observations, men
who sail the ships or fly the planes to transport observers to their
chosen positions, men who cook meals often under impossible con-
ditions, men and women who spend long, often tedious hours, to
work up the data and prepare reports for the World Data centers;
those who type, draw, reproduce and mail, and finally those very
few who will interpret the welter of data and provide new
knowledge.

The sea and the continents more often than not will be the
only non-cooperative IGY participants in our struggle to under-
stand the earth in order to learn how to become master rather than
slave of our environment. The instruments, whether a fancy sat-
ellite or the old reliable Nansen bottle, by themselves are valueless.
The brains, the work, and the enthusiasm of thousands of men and
women all over the world are the newsworthy items during
the IGY.

EDITORIAL

Summer & Autumn 1957, Vol. V, Nos. 3 & 4

G

ENERAL concepts are difficult to convey, and none is more
difficult than that of basic research in science"; so begins a report
just issued by the National Science Foundation.

As practically all of the articles in this issue concern basic
research, it may be well to quote further from the report: "... the
emphasis given in the news to the exceptional, unusual, 'news-
worthy' aspects of new inventions and developments, often lack
reference to the fundamental work without which these could not
have been made. The word 'research' in advertising often is used
to mean testing, development or invention. Seldom, indeed, is it
employed, except by scientists, to mean simply the search for new
knowledge and better understanding of the physical world of man,
and of man's environment."

The basic research of theoreticists led to the discovery of a
countercurrent under the Gulf Stream, as is reported in this issue.
This, indeed, is new knowledge. Not often do new findings have
immediate practical application. In this case as a result of British-
American cooperation, our concepts of oceanic circulation have
changed and will result in a much more meaningful interpretation
of the oceanographic IGY observations.

CRAWFORD 40

DISCOVERY

DISCOVERY 24° N

L/57 CRAWFORD 16° N

4/57X CRAWFORD 8°N

/ 58 CRAWFORD

2/57 CRAWFORD

Atlantic IGY Program — This chart clearly shows how much of the work has
been done already by the small R. V. Crawford. Month and year are indicated
to left of ship's name.

C. O'D. Iselin

Synoptic Studies

in

Oceanography

Our IGY program after a slow start already has
accomplished a great deal.

JL\. central and classical prob- ships. The distribution of such
lem in physical oceanography is data is very uneven, both in
to try to understand the circu- time and in space. The accuracy
lation of the oceans as a whole, of even the best observations
In order to do this it is first has been satisfactory only dur-
necessary to be able to describe ing the past 30 years or so. Only
the three-dimensional distribu- one ocean, namely the South
tion of the physical and chemical Atlantic, has ever been surveyed
properties of the whole fluid systematically and in a manner
envelope. Until now it has only that could be regarded as pro-
been practical to secure satis- viding a synoptic picture of the
factory data from rather limited deeper water masses. Never-
areas. Only a small percent of theless, it has become possible
the observations have been from to describe the physical and
depths greater than 3,000 me- chemical structure of the
ters, although most of the ocean oceans in broad outline, and in
is nearly twice this deep. recent years through multiple-
Oceanographers have had shiP °Perations a beginning has
to be content to study a sort been made in the syn°Ptic
of average ocean constructed ^ography of ^ted areas.
, ,. . There is every expectation

from the observations of tern- .-, , ,u u ,, T , ' ,

that through the International

perature and salinity and dis- Geophysical Year the basic data

solved oxygen obtained by many of physical oceanography will

be improved by a whole order
of magnitude. If present plans
can be carried out this will be
especially so for the deeper
water masses.

It must be admitted that
oceanographers at the working
level in this country were at
first not too enthusiastic about
the prospects of adding signifi-
cantly to our understanding of
oceanic circulation during the
International Geophysical Year.
It was argued that our ships
were already working on a
year-round basis and that the
existing research programs at
our laboratories were the best
that could be devised. When the
desirability of periodic re-
surveys of the whole system of
currents was pointed out, few
oceanographers at the working
level had the patience to wait
for another 30 years or so before
it might be practical to learn
about any gradual changes that
might be taking place. Some of
us also felt that we were being
asked to plan a survey of the
oceans that our sons would ap-
prove and want to repeat and,
because of the many changes in
our concepts of the basic prob-
lems during recent years, there
was doubt that any program
that could now be organized
would in retrospect seem wise.

Stimulation

During the planning period
at least three factors have
helped to stimulate enthusiasm

for the IGY oceanographic pro-
gram. In the first place, no one
foresaw how many research
vessels would be able to co-
operate. As soon as it became
evident that as many as 60 ships
might become available many
people's attitudes, including my
own, changed rather abruptly.
For some reason international
cooperation in oceanography
has been slow to develop, al-
though of course it has been
obvious all along that no one
nation is likely to bring to bear
sufficient resources to do a thor-
ough job of studying more than
a limited part of the world's
oceans. However, with so many
ships available it would indeed
be possible to gain a rather
complete look at the deeper
waters on a somewhat synoptic
basis. The fact that all the data
would be secured within a two-
year period would be quite
satisfactory in this case, for the
deeper currents are believed to
be sufficiently slow so that not
much change is likely to occur
in the system during that
period.

A second encouraging factor
stems from the recent observa-
tions of Mr. L. V. Worthington
of the Woods Hole Oceano-
graphic Institution. He has
shown that below a depth of
about 2,500 meters in the west-
ern half of the North Atlantic
the waters today contain about
.3 cubic centimeters less dis-
solved oxygen per liter than

was the case 25 or 30 years ago.
This is strong evidence that the
deeper water has not been re-
newed during this period. Thus
an easily measurable change
has taken place in the North
Atlantic and it will be interest-
ing to learn whether or not
slow trends are also taking
place in other areas. In the case
of the South Atlantic a particu-
larly complete survey of tem-
perature, salinity, and dissolved
oxygen was made by the Ger-
man ship Meteor during the
period 1925-27. Thus, to repeat
some of these observations be-
came one of the major objec-
tives of the U. S. oceanographic
program for IGY.

A third factor to arouse inter-
est in deep currents has been
the recent success of Dr. J. C.
Swallow of the National Insti-
tute of Oceanography in
England in obtaining direct
measurements of the flow at
considerable depths. In the past
the interpretation of deep meas-
urements of temperature and
salinity in terms of direction
and velocity has been beset by
many uncertainties. The ques-
tion can be stated in deceptively
simple terms: How deep are the
more powerful, permanent
ocean currents? If they are rel-
atively shallow, extending only
to 1,500 meters or so, then belov/
them the distribution of density
and the available theory demand
that deep countercurrents exist.
During recent years many dif-

ferent kinds of studies have
been made in an effort to re-
solve this problem but until Dr.
Swallow developed neutrally
buoyant floats there was little
hope of gaining a clear-cut
answer.

The influence of these three
developments on the U. S. At-
lantic IGY oceanographic pro-
gram has been marked. So
enthusiastic have people grown
that a good deal of the work has
already been completed. Similar
efforts in the Pacific lack the
stimulus of as complete a set of
early measurements for com-
parison with the deep physical
and chemical situations of to-
day, but it seems safe to say
that the successes to date in the
Atlantic are likely to encourage
corresponding efforts in other
areas.

Preliminary Results

As mentioned above, the
Atlantic oceanographic program
has already achieved some pre-
liminary results. In trying to
predict what the whole under-
taking will amount to, it may
be helpful to discuss these first
observations.

The program really began in
March when the British re-
search vessel Discovery II and
the Atlantis met at Bermuda.
During the next six weeks their
joint operations were so pro-
ductive that a real milestone in
physical oceanography was
achieved. The area selected for

the work was the outer edge of
the Blake Plateau at about the
latitude of Charleston. It was
known from previous Atlantis
temperature and salinity sec-
tions that in this area the deep
water flow (whatever its direc-
tion) was forced well east of
the swift and much shallower
Florida Current by the Blake
Plateau. Thus in this area the
ships would not be handicapped
by strong surface currents in
their efforts to relate deep water
movements to deep density
structure. (Farther north the
deep density gradients are just
as pronounced, but they lie
more directly under the Gulf
Stream.) Because of the avail-
ability of Loran navigation in
this area, both ships could have
excellent navigational control.

While the Atlantis measured
the deep temperature and salin-
ity structure often as close as
two miles apart, the Discovery
tracked neutrally buoyant floats
drifting with the water at pre-
selected levels. The floats con-
tained a sound source and the
tracking was achieved through
two hydrophones suspended
from the bow and stern of the
Discovery.

With the float at 2,000 meters
the net motion at the end of 4
days was so close to the ac-
curacy of navigation that the
total drift of only a few miles
was not significant. Shallower
floats clearly drifted to the
northeast, as was expected, and

with the expected velocities.
But a float set out at 2,800 me-
ters went toward the southwest
at about 8 miles per day. Thus,
in this part of the North Atlan-
tic, the level of minimum mo-
tion is about 2,000 meters and
below this the current is moving
surprisingly rapidly in the op-
posite direction.

Many more such observations
are needed, of course, before it
can be known with certainty
how widespread this unexpected
phenomenon may be, but at
least two things were made
very clear by the work accom-
plished to date: that through
international pooling of ships
and observers results were
achieved that neither group
could have accomplished alone;
furthermore, that it should be
possible through similar oper-
tions in a few other carefully
selected areas to interpret with
considerable assurance the
great mass of deep temperature
and salinity observations that
will be secured by the other
IGY ships. Just a few weeks'
work by two ships has made
the whole deep-water program
much more meaningful. Until
this operation, the main hope
that scientific sense would be
achieved was that somehow the
chemical observations made dur-
ing the IGY could be brought
into agreement with the move-
ments of the water deduced
from the distribution of density.
There is always some uncer-

tainty in this general approach
to the deep circulation problem.
We do not know quantitatively
how much the distribution of
the generally observed chemical
elements is changed through
biological activity.

On her way back to Plymouth
from the operations off Charles-
ton, with some help from the
people at Woods Hole, the Dis-
covery achieved the most com-
plete North Atlantic profile to
date. Temperature, salinity, and
oxygen were measured at 40
stations on a line from the
Grand Banks of Newfoundland
to the approaches to the English
Channel. This work sets a very
high standard for completeness
and accuracy which the other
European ships crossing this
area during the next 18 months
may be hard pressed to match.
The accuracy of the salinity
determinations was especially
high due to the use of a new
sea-going conductivity bridge
developed recently at Woods
Hole.

Meanwhile, the research ves-
sel Crawford from Woods Hole,
under the skillful leadership of
Mr. F. C. Fuglister, had made
four complete Atlantic cross-
ings; two in the tropical North
Atlantic and two in the tropical
South Atlantic. The two latter
sections are duplicates of two
of the Meteor crossings of 30
years ago. In short, we have
already realized five complete
Atlantic east-west profiles and

This paper was presented at
the Twelfth Meeting of the U. S.
National Committee for the
International Geophysical Year,
National Academy of Sciences,
June 27-29, 1957. The Proceed-
ings of this meeting will be
published soon in a single
volume.

three more are scheduled for
the same ships before the end
of the year.

The reasons for "jumping the
gun" with the Crawford are the
same that prompted Dr. Maurice
Ewing of the Lament Ge-
ological Observatory to send the
Vema into the South Atlantic
last winter. Next winter the
Atlantis and the Vema are
scheduled to operate together in
the South Atlantic during a six-
month period. It was felt that
we could make much more ef-
fective use of this time if we
had the benefit of some recon-
naissance. Furthermore, the
Russian and the Argentine ships
that will cruise in the South
Atlantic during the next year
or more could also benefit.
When the work of the Crawford
and the Vema has been studied
in a preliminary manner, we
should all be in a much better
position to plan wisely for the
main assault.

Crawford Data

Since the Crawford only re-
turned to Woods Hole on June
1st after a four-month voyage,

TEMPERATURE (°C).
16° SOUTH LATITUDE,
- SOUTH AMERICA - AFRICA
CRAWFORD STATIONS 121 - 153 ,
APR. 1-22,1957

8

SALINITY (%0).
16° SOUTH LATITUDE.
SOUTH AMERICA - AFRICA

z

CRAWFORD STATIONS 121 - 153 *
APR. 1-22,1957

I can give here only one ex-
ample of her work. This is a
profile of temperature, salinity,
and oxygen following Latitude
15° 45'S. This is a reoccupation
of one of the Meteor sections.
The sampling intervals both
vertically and horizontally are
indicated by dots on the profile.
In comparison with the Meteor
profile about twice the number
of observations were secured.
So far as temperature is con-
cerned there are no striking
changes. The deep temperature
gradients near the South Amer-
ican continental slope are steep-
er than in the Meteor profile,
but in all probability this is just
a consequence of the closer sta-
tion spacing. The temperature
maximum at mid-depths in the
west has increased by about

.3°C. The salinity profile, too,
corresponds very closely to the
one secured by the Meteor.
There is more detail in the
slight salinity fluctuations at
mid-depths, due both to the
greater accuracy of new observ-
ations and to the more closely-
spaced points of observations,
but at first look there seems to
be no large-scale differences.

On the other hand, there have
been quite pronounced changes
in the dissolved oxygen values
during the 30-year interval. This
is most easily seen by compar-
ing the individual oxygen-depth
curves shown in Figure 4. Es-
pecially near the two ends of
the profile there is more oxygen
today in the oxygen minimum
layer and less in the deeper
waters. The Antarctic bottom

OXYGEN H/i)

16° SOUTH LATITUDE,
SOUTH AMERICA -AFRICA
CRAWFORD STATIONS 121-153,
APR. 1-22,1957

water at depths below about
4,000 meters in the western
basin has lost as much oxygen
as the deep water in the western
basin of the North Atlantic.
Presumably of recent years the
deeper water is not being re-
newed because sufficiently dense
surface water is not formed in
winter, either in the far north
or the far south. It is interesting
to speculate about how long the
trend will continue.

The three other 1957 Craw-
ford profiles are of just as high
quality and I think that all
oceanographers will agree that
this is a remarkable piece of
work for so small a vessel; the
Crawford when fully loaded
displaces barely 300 tons. The
data shown here are just one
part of a much broader program
of observations.

Those who are familiar with
the recent papers of Dr. Georg
Wiist of Kiel University know
the immense amount of work
that he has devoted over a long
period of years to the interpre-
tation of the Meteor profiles in
terms of transport and velocity.
He has worked out some fairly
convincing arguments that there
are three levels of minimum
motion in the South Atlantic.
The cold and relatively fresh
Antarctic bottom water has a
northward component, the great
mass of water at mid-depths
having salinities just above
34.90 %0 has a southward com-
ponent. The salinity minimum

layer with its axis at about 700
meters is moving north, while
nearer the surface there is a
southward component. Although
most oceanographers will agree
that the net components of mo-
tion are in these directions at
the various levels, the rates of
flow computed by Wiist seem to
some of us to rest on much
shakier ground. Thus, it will be
of great interest to set out next
winter some of the Swallow-
type, neutrally buoyant floats
at the critical points in these
South Atlantic profiles. Study
of the new Crawford profiles
will help in the selection of the
best depths and locations for
gaining this very positive type
of observation.

To gain reliable information
about the surprisingly swift and
narrow deep flow in both the
North Atlantic and South At-
lantic, the most thoroughly
explored and best understood
oceans, will not only be of in-
terest in itself, but will also help
greatly in the interpretation of
the deep observations that will
be made by ships operating in
the South Pacific and Indian
Oceans, which are nearly virgin
territory so far as three-
dimensional oceanography is
concerned

Forward Stride

The rate of overturn of the
oceans as a whole is not just an
oceanographic problem that is
basic to many lines of inquiry

10

A compass and ping pong ball suspended below an underwater camera indicate
a southward drift only 18 inches above the ocean bottom in this photograph

taken from the R. R. S. Discovery II.

in biological and geological
oceanography, as well as in
physical and chemical studies.
Since the ocean acts to some
degree as the flywheel in the
great heat engine in which the
motions of both the atmosphere
and the hydrosphere combine
and interact with each other,
such studies are also basic to a
better understanding of climatic
trends, to the possible use of the
deep ocean for the disposal of
radioactive waste materials, and
to other more or less practical
matters. In the past the prob-
lem has been attacked by many
individual investigators and by

a few research vessels working
independently. This will be the
first time that a large portion of
the world's talent and facilities
for oceanography will be work-
ing within an agreed coopera-
tive program.

If the quality of the data
secured during the past winter
by the Atlantis, the Crawford,
and the Discovery can be
matched by most of the other
vessels taking part in the Inter-
national Geophysical Year pro-
grams, there is little doubt that
a considerable stride forward
in our understanding of the
oceans will soon be achieved.

11

Since her commissioning: in July 1956, the R. V. Crawford has sailed 39,800 miles
during fifteen cruises. Her present cruise will bring the total to 49,810 miles

by mid— December 1957.

12

by G. E. R. Deacon

The Pinger

Recent British- American co-operation in oceanography
led to the discovery of a counter cur rent under the Gulf Stream.

I

T is more than one hundred
years since the existence of cold
water at the bottom of the trop-
ical oceans showed the deep
undercurrents from polar re-
gions, and now deep currents
have the same interest for ma-
rine scientists as upper-air
winds for meteorologists. To
measure the deep currents was
a difficult problem. Current
meters lowered from ships an-
chored in deep water allowed
only slow and uncertain pro-
gress. Clearly little advance
could be made without some
submarine counterpart to the
meteorologist's upper-air bal-
loon, some device that could
signal its movements by acous-
tic methods since we cannot
look down into the ocean.

The first attempts used an
acoustic transmitter sinking

very slowly under a string of
parachutes. When this proved
too difficult, Dr. J. C. Swallow
suggested the much more prac-
tical idea of a transmitter en-
closed in a container so con-
structed that it sinks to a pre-
determined depth and there
drifts with the water. He used
aluminum scaffold tubing closed
at the ends to make containers
that are less compressible than
sea water. Therefore, if loaded
heavily enough to sink at the
surface, they gain buoyancy as
they go down. The depth at
which they will float can be ar-
ranged within narrow limits
The floats drift along with the
water, sending out sound pulses
which can be picked up by hy-
drophones in a surface ship up
to distances of several miles in
fairly bad weather. With the
help of navigational aids, echo

13

sounding, anchored marker
buoys and radar, the floats can
be tracked closely enough to
show deep tides and currents.
Not an easy routine; deep float
tracking demands close atten-
tion and cooperation among all
engaged in the measuring and
in the handling of the ship.

Developed at the (British)
National Institute of Oceanog-
raphy, the technique cannot be
used to full advantage until it
is more widely adopted and
used on the most rewarding
problems. Until a few months
ago the Discovery II had fol-
lowed 12 floats for several days
at different depths in several
parts of the eastern North At-
lantic Ocean, as much of the
work as possible being done in
co-operation with other marine
laboratories. The measurements
are a considerable addition to
our knowledge of the sea and
the technique was improved so
that it could be used in all but
the worst weather.

A Theory

Progress in the theory of
oceanic circulation is fastest in
the United States. A number of
young scientists, stimulated by
advances in dynamic meteorol-
ogy and working close together,
are taking realistic account of
the drag of the prevailing
winds, the effect of the earth's
rotation, the density layering of
the oceans and the frictional
forces which can transfer and
dissipate energy. Mr. H. Stom-
mel of the Woods Hole Ocean-
ographic Institution, one of the
most active workers, has cam-
paigned for measurements of
the water movements at great
depths below the Gulf Stream.
He maintains that there should

Dr. Deacon is director of the
National Institute of Ocean-
ography in Great Britain. His
first experience was gained
thirty years ago in the Antarctic
Ocean. His chief aim is to en-
courage theoretical and exper-
imental studies of the water
movements and the interchange
of energy with the atmosphere.

be a considerable southward
movement, _ as implied in his
two-layer theory of the ocean.
It might explain why the Brazil
Current in the South Atlantic
is so weak compared with the
Gulf Stream in the North At-
lantic.

A Plan

The National Institute of
Oceanography could not have
sent the R. R. S. Discovery II
across the Atlantic Ocean with-
out generous help from the
Woods Hole laboratory. The
work would not have been ef-
fective had the R. V. Atlantis
not been there to carry out close
temperature and salinity meas-
urements from surface to bot-
tom in the investigated area.
These observations allow the
construction of isobaric charts
for the sea, like those in weath-
er reports, and such charts can
be used to calculate the water
movements if some initial as-
sumptions can be checked by
direct measurements.

A Result

Work on these lines by Defant
and Wust pointed to the exis-
tence of an area of little or no
horizontal movement at a depth
of 5000 to 6000 feet below the
Gulf Stream with northward
movements above and south-
ward movements below, but

14

Block diagram of eastern coast of United States. Heavy arrows show the path
and direction of the Gulf Stream's surface water issuing from the Florida
Straits and flowing over the relatively shallow Blake Plateau. At Cape Hatteras
the stream breaks away from the coast to flow eastward into deep water. The
smaller arrows show the
deep countercurrent as pre-
dicted by theory. The Maltese
cross marks the region where
the Discovery II and the
Atlantis found the predicted
current.

before this joint operation no
one had measured the south-
ward current and we could only
guess its speed if it really was
there. The northward flowing
Gulf Stream was strong near
the surface. There was little or
no movement between 4500 and
6000 feet and three floats at
8200 feet and four at 9200 feet
went south. One of the deepest

did l/s knot steadily, travelling
23 miles in 66 hours. Photo-
graphs of the deflection of a ball
suspended by string from a
compass only 18 inches above
the bottom still showed an ap-
preciable southward movement.
Without full account of such
massive movements at great
depth it is clear that no at-
tempt to understand the surface

15

currents and their variations
could be complete. It will be
some time before the observed
currents, density, and pressure
distributions can be fully con-
sidered, but there is no doubt
that this collaboration between
the British and U. S. laborator-
ies is a landmark in Marine

Science. The comparison of di-
rect measurements with the
conclusions based on density
distributions will add greatly to
the value of much work of this
nature which is to be done in
the International Geophysical
Year.

Gifts and Grants

Two grants were received
from the National Science Foun-
dation. $36,700 for support of
research entitled "Chemical
Composition of Phytoplankton
as Related to Environmental

Changes" under direction of Dr.
Bostwick H. Ketchum.

$56,700 for support of research
entitled "Measurement of Light
in the Sea" under direction of
Dr. George L. Clarke.

Currents and Tides

Dr. G. Wiist has asked us to
correct two statements made on
pp. 33-34 of the last issue. Dr.
Wiist was the chief of the phys-
ical oceanographic work of the
Meteor expedition and scientific
advisor to the general leader:
Captain F. Spiess, German
Navy.

The story of the scientist and
the sea serpent turned out to

be an old one and did not in-
volve Dr. Bruun. We deeply
regret the printed inaccuracies.

Dr. Joanne S. Malkus and
Claude Ronne invaded a foreign
domain and flew thousands of
miles across the Pacific Ocean
to study cloud formations. An
official protest from Scripps may
be expected at any moment.

Any back issues available?

As there is a constant demand
for back issues the Editor will
be most appreciative if un-
wanted copies of Oceanus can

be returned to him. Postage will
be refunded.

Particularly needed are the
first issues of Volumes I and II
and Volume III, number 3.

16

srfjiSite.

A Breaching Humpback

Humpback whales are very
frolicsome and are often seen
thrashing about at tne surface,
waving their tails and flippers
in the air and smacking the
water with them. By far their
most spectacular stunt is leap-
ing partly or entirely out of the
water — "breaching", the whal-
ers called it.

Good photographs of these
acrobatics are rare; usually the
camera catches only the ensu-
ing splash. This picture is one
of a small number of successes
and was taken by William M.
Dunkle, Jr., from Atlantis on
22 July 1957 off the northeast
end of Georges Bank. It is con-
siderably enlarged; in the orig-
inal the whale covered only 1.8
mm., about one fourteenth of an
inch.

These acrobatics have been
variously and often extrava-
gantly explained; they are the
observational basis for the ac-
counts of battles between
thrashers, sharks, or swordfish
(which the reporters do not
ordinarily see) and the whales.
Another favorite explanation is
that the whales are trying to
rid themselves of parasites.
However, it seems simpler for
the present to suppose that
these antics are mere playful-
ness. It may be worth noting
that in all the breachings I have
seen the whale has hit the water
on its back, as this one did; in
some published photographs
the whale is on its side, evi-
dently on its way over.

W.E.S.

17

Associates' News

Welcome Gifts

Associate Samuel A. Peck
recently donated the 32-foot day
cruiser "Gay Song" to the In-
stitution, to be used or disposed
of in any way the Institution
desires.

This is the second time Mr.

Peck has helped our program
in this way. In 1952 he donated
the 45-foot sportfishing boat
"Allure".

A gift of $500. was received
from Life Member Mr. Donald
B. Straus.

New Industrial Associates

The Carter Oil Company Tulsa, Oklahoma

Chance Vought Aircraft Incorporated Dallas, Texas

Coastal Oil Company Newark, New Jersey

United Fruit Company Boston, Massachusetts

New Life Members

Mr. and Mrs. D. H. Braman, Victoria, Texas

Mr. and Mrs. Laurance S. Rockefeller, New York, N. Y.

Gifts and Grants

The Esso Education Founda-
tion renewed a $3,500. grant to
the Institution with the state-
ment: "The Foundation feels
that the program toward which
this contribution is made is a
worthy one and hopes that its

grant will be helpful in achiev-
ing its objectives."

The Gulf Research and Devel-
opment Company made a gen-
erous gift of equipment and
supplies, including six Nansen
bottles and a large orange-peel
dredge.

Basic Research Report

The National Science Foundation report mentioned in our
editorial presents a strong case for the increased support for basic
research from private as well as public sources. The report sug-
gests re-definition of tax exemption privileges for non-profit
research institutions and changes in the Federal income tax laws
to stimulate private philanthropic giving for basic research.

Copies of Basic Research — A National Resource, 1957, may
be purchased for 45 cents from the Superintendent of Documents,
U. S. Government Printing Office, Washington 25, D. C. The Insti-
tution has a number of copies available for interested Associates.

18

The

rma

Circulation

by George Veronis

Radical new thoughts on the movement of the ocean's water
masses are being tested during the I. G. Y.

I

N 1955, Henry Stommel of this
Institution theorized the exis-
tence of a deep countercurrent
under the Gulf Stream. In
March of this year the Discovery
II — Atlantis expedition found
that this current indeed existed
— an observation which calls
for a major revision in the fun-
damental concepts of dynamic
oceanography.

The deep countercurrent, ac-
cording to Stommel's thermo-
haline theory, is a result of
changes in temperature and sa-
linity which produce density
differences which in turn pro-
duce the circulation. In almost

all previous theories of the
general circulation the ocean
currents are considered to be
driven by the major wind sys-
tems which could be modified
by density differences, but in
which salinity and temperature
changes did not set up sizable
currents. It now seems clear
that thermodynamic forces must
be as important as the wind in
setting up the large-scale cur-
rent systems in the ocean.

The Discovery II — Atlantis
cruise brought to a close a co-
operative effort which is per-
haps unparalleled in the history
of oceanography. In the twenty-

19

REDICTION FOR DEEP CURRENT

This chart shows a theoretical prediction of the pattern of flow in deep water
(the average transport beneath 2000 meters). From temperature-salinity distri-
bution it seems evident that the deep water all over the world is supplied at
two source regions indicated by the heavy black circular areas off Greenland
and the Weddell Sea. This water is then distributed all over the world where
it gradually rises at the rate of a few centimeters a day up through the main
thermocline. The chart shows the actual distribution of these deep currents as
predicted by the simple theory. There are a number of rather startling
predictions:

The white areas indicate clep

In central oceanic areas the cold deep water flows away from the Equator,
not away from the poles!

There is a countercurrcnt under the Gulf Stream and the Agulhas Current.
The current under the Brazil Current and Korushio is not a countercurrent.
There is a marked deep current toward the north off New Zealand flowing
along the western wall of the Tonga-Kermadec trench. One should find
high velocities and a very narrow current.

'Pths over 4000 meters.

21

month period between Stom-
mel's proposal and the actual
observation, Dr. John B. Swal-
low of the (British) National
Institute of Oceanography de-
veloped the neutrally buoyant
float; the joint cruise was ar-
ranged in order to test both
Stommel's theory and Swallow's
instrument; and a careful pro-
gram was planned whereby the
Atlantis under the leadership of
L. V. Worthington was to make
standard oceanographic stations
(i.e., gather data on salinity and
temperature against depth) with
which to guide the Discovery
II in its choice of points at
which the buoys were to be re-
leased.

The most significant aspect
of the joint venture is the
marked interdependence of the
three phases of it. Stommel's
analysis is based on assumed
rising and sinking of large
water masses in the sub-polar
regions, an assumption which
cannot easily be checked. The
only alternative for determining
the validity of the theory was
to test the results by observa-
tion. Since the deep counter-
current under the Gulf Stream
is the most pronounced feature
of the model, the determination
of its existence served as the
crucial test of the validity of
the theory. For this it was, of
course, necessary to have an
instrument for measuring deep
currents.

It was fortuitous that Swal-

Dr. Veronis, Research Associate
in Mathematics, is interested in
transient and thermal circula-
tion. He was formerly at the
Institute for Advanced Study
at Princeton.

low had been designing just
such an instrument.* When he
had developed the float to the
point where it was ready for a
field test, the two institutions
arranged the joint cruise. The
Blake Plateau was specifically
chosen as the testing ground.
There, because of the gradual
slope of the continental shelf,
the surface portion of the Gulf
Stream is farther inshore than
the deeper portion. Thus the
Discovery would not have to
work against the surface Gulf
Stream during the tracking of
the float. The Atlantis preceded
the Discovery II to the site and
made hydrographic stations at
several locations in order to de-
termine the most appropriate
points for releasing the buoys.

Seven buoys were released
(at different times) at various
depths between 2000 m and
2800 m. The buoys all moved es-
sentially to the south with
speeds ranging from 2.8 centi-
meters per second to 17 centi-
meters per second. The existence
of the countercurrent was es-
tablished beyond a doubt.
Theories

Until the end of World War
II no dynamical theory of the

* See page 13 in this issue.

22

Interpretation of the total water transport in the surface layer (left) and bot-
tom layer (right) of the Atlantic Ocean. The small circles indicate where water

sinks or rises across the level surface.

general circulation of the oceans
existed. Suggestions had been
made of the probable factors
determining the general circula-
tion but no model had been
worked out. In a remarkable
paper, published in 1933, Golds-
brough had been able to repro-
duce theoretically a circulation
resembling that of the Atlantic
Ocean. There were, however,
severe restrictions in his theory
which at the time seemed in-
surmountable. Over a long per-
iod of time new concepts have
evolved and were formally
realized by Stommel in 1956.

The first important step to-
ward an understanding of the
general circulation was made
by Stommel in 1947. He showed
that the rotation and curvature
of the earth are the essential
factors producing the observed
intensification of currents on
the western sides of the oceans.
This westward shift is inde-

pendent of the form of the
boundaries or of the frictional
forces which are assumed to
keep the flow in a steady state.
Stommel considered an ocean
with rectangular boundaries and
bottom friction, both of which
are clearly unrealistic but nei-
ther of which is essential to his
argument.

In 1950 Munk attempted to
refine Stommel's model by elim-
inating bottom friction. He
showed that it is possible to
attain a steady state with the
assumption that the retarding
force be concentrated at the lat-
eral boundaries. Later in 1950
Munk and Carrier applied
boundary layer methods to a
triangular ocean (roughly the
shape of the Pacific) and de-
rived results similar to the pre-
vious rectangular ocean model.

It now appears that the actu-
al dissipative mechanism in the
oceans is more complicated than

23

FIG. 1

that envisaged by Munk. His
essential contribution was the
careful determination of the
total stress applied to the North
Atlantic by the prevailing wind
system. Since the ocean can be
considered frictionless except
for the boundary regions, the
stress over the interior portion
of the ocean determines the net
amount of water transported by
the circulation. Thus the pre-
cision of Munk's result could be
checked observationally by a
measurement of the transport
through the Gulf Stream.

A Discrepancy

At this point in the analysis
a puzzling discrepancy ap-
peared. Munk's computation in-
dicated that the Gulf Stream
transported 35 million cubic
meters of water per second.
Observations indicated a value
of 70 million. There appeared to
be no way to resolve the dis-
crepancy.

There were other dilemmas
also. The wind system in the
South Atlantic is equivalent in
magnitude to that over the
North Atlantic, so that theo-

retically the wind should pro-
duce a southward flowing Brazil
Current comparable in intensity
to the Gulf Stream (fig. 1). In
reality as indicated by the dy-
namic topography there is prac-
tically no Brazil Current.

Two Layer Ocean

In 1955 Stommel found a way
of incorporating the thermoha-
line* component of the circula-
tion into a dynamical model.
This circulation would be the
result of large-scale rising or

FIG

sinking of water masses in the
sub-polar regions. Stommel as-
sumed that the ocean is divided
into two layers and that water
from the upper layer sinks to
the lower layer in the sub-arctic
region. In the sub-antarctic, low-
er layer water rises to the upper
layer. Although the mechanism
for such a water mass exchange

* The name "thermohaline", meaning
literally "temperature-salinity" is de-
rived from the fact that changes in
temperature and salinity produce
density differences which in turn
produce the circulation.

24

is not investigated, this sugges-
tion is in accord with an obser-
vational study of the southern
ocean by G. E. R. Deacon as a
result of the series of oceano-
graphic cruises made by the
Discovery II in the years
1929-39.

The result of the proposed
exchange of water masses in
the Atlantic would be a strong
narrow current, northward at
the surface and southward in
the lower layer, along the entire
western edge of the Atlantic
(fig. 2). If this current is simply
added to the wind-driven cur-
rent, the net result on a chart of
the Atlantic Ocean is as shown
in fig. 3. From figs. 1 and 2, it
can be seen that at the surface
a superposition of the two cur-
rents intensifies the Gulf Stream
and weakens the Brazil Current.
In the lower layer the reverse
is true, i.e., the Gulf Stream is
weakened and the Brazil Cur-
rent strengthened. Since the
wind-driven currents decrease

FIG. 3

sharply with depth, the therm-
ohaline bottom current is the
dominant one and the flow un-
der the Gulf Stream is actually
to the south.

The consequences of Stom-
mel's model have been con-
firmed in one part of the ocean
by the Discovery II — Atlantis
expedition. See p. 15. Moreover,
from 1933 Meteor expedition
data, Georg Wiist has com-
puted strong southward deep
currents off the coast of Brazil.
The model also explains the
very weak dynamic topography
of the Brazil Current. A final
indication of the validity of the
theory is that the net northward
transport in the Gulf Stream is
reduced by about a factor of
two thus bringing it into agree-
ment with Munk's computed
transport.

The conclusion which one
must draw, therefore, is that the
ocean has a strong thermal cir-
culation. Many questions are
raised by the existence of such
a flow.What complex non-linear
interaction exists between the
thermohaline and wind-driven
boundary currents? Is the Ant-
arctic Circumpolar Current an
integral part of the Atlantic
circulation through the water
mass exchange? Is it meaningful
to talk any longer about a one-
ocean circulation or does the
general circulation encompass
the flow of all the world's
oceans? These and many other
questions arise. It seems to be
a good way to start off IGY.

25

The heat and wafer budget of the earth will be studied
intensely during the /GY.

HE great saga of the Norse
kings, the "Heimskringle", be-
gins with the words "Earth's
round face, whereon mankind
dwells". The Vikings, like other
primitive peoples, thought of
Earth as their home and of
themselves as its creatures. To-
day we know that Earth is the
only planet of our solar system
on which human life could have
developed, for no other satellite
of our sun has land masses sur-
rounded by an ocean of liquid
water or an atmosphere con-
taining abundant free oxygen.
Our bodies are made up al-
most entirely of four elements
drawn from sea water and air,
hydrogen, carbon, oxygen and

nitrogen. The narrow tempera-
ture range in which we can
survive is maintained by the
great heat capacity of the sea
and the atmosphere. The waste
products that otherwise would
suffocate us are continuously
dispersed by the easy motions
of the atmosphere. We can exist
as land animals only because
the sun's deadly ultraviolet and
X-rays are fended off by the
protective shield of the air, and
because the great natural en-
gine of the sea and the atmos-
phere pumps water continuously
from the sea surface and pours
it gently down upon the land.
Yet from our point of view,
the earth is a careless mother.

26

Sun,

Sea

and

Air

by Roger Revelle

Large areas of her surface are
too hot or too cold, too dry or
too wet to support any large
number of human beings. More-
over, she is unreliable. Areas
where there was once sufficient
water for men to build civiliza-
tions are now so dry that only
a few desperate nomads can live
in them. Elsewhere, a mile-
thick blanket of ice has crept
down and obliterated once green
farms and forests. Millions of
our species suffer when a slight
change in the running of the
sea-atmosphere engine causes
drought or flood. Sometimes the
engine runs with unpleasant
violence. Then thunderstorms
and hurricanes, tornadoes and

typhoons bring destruction and
death to many of us.

Because of our dependence
on events taking place in the
air, almost everyone is an ama-
teur meteorologist. Wherever
two or more people are gath-
ered together the first topic of
conversation is the weather, and
this was probably just as true
in the time of Hammurabi or
Amenhotep as it is today. Pro-
fessional weathermen are a
new development, however, and
it has only been within the last
few decades that we have begun
to gain an understanding of the
great interrelated mechanisms
of the air and the oceans.

27

The Sun

We know that the sun pours
a flood of particles and visible
and invisible light into the top
of our atmosphere. The amount
of visible light appears to be
nearly constant, but the inten-
sity of ultraviolet and X-rays
and the number of particles
varies by at least a hundred-
fold. The particles are chiefly
electrons and protons. The av-
erage number of hydrogen nu-
clei entering our atmosphere is
surprisingly large, perhaps a
billion per square centimeter
per second. During the geolog-
ical lifetime of the earth, if all
this hydrogen were combined
with oxygen as water, it would
correspond to a layer over the
ocean about twenty meters
thick. The energy carried to the
earth by these particles from
the sun during periods of sun-
spot activity may be as much as
one tenth of the total energy of
sunlight.

In addition to particles of
ordinary hydrogen, there is new
evidence that most of the tri-
tium or radioactive hydrogen
on earth also comes from the
sun. It was formerly thought
that all the tritium was pro-
duced by cosmic rays bombard-
ing nitrogen and oxygen mol-
ecules in the upper air, but
recent calculations indicate that
the amount present is nearly
ten times too large to be pro-
duced in this way.

The marked variations in
ultraviolet radiation and in the
number of particles coming
from the sun cause large varia-
tions in the temperature and in
the electrical and magnetic be-
havior of the upper atmosphere,
because there is such a small
amount of air at these high

levels. Neither the majority of
particles nor the ultraviolet
rays penetrate very deeply,
however, and it is not clear
whether the variations in the
amounts coming from the
sun have appreciable effects
near the earth's surface. Vis-
ible light is the dominant form
of solar energy entering the
lower atmosphere. Part of this
light is reflected back to space,
chiefly from the surface of
clouds, snow and ice. Most of
it is absorbed in the atmosphere
and the sea, from which it is
ultimately re-radiated as infra-
red radiation.

In this respect, the atmos-
phere behaves much like the
glass in a greenhouse. It easily
transmits visible light but is
rather opaque to the infrared
or heat radiation coming from
the ground and the sea surface.
Just as in a greenhouse, the air
temperature must be consider-
ably warmer than it would be
in the absence of materials that
absorb infrared, in order to al-
low a balance between incoming
and outgoing radiation. In the
greenhouse the absorbing ma-
terial is the glass roof. The cor-
responding materials in the
atmosphere are three substances
present in quite minor amounts:
water vapor, carbon dioxide and
ozone.

The temperatures in the up-
per air do not vary markedly
with latitude and consequently
the amount of back radiation is
roughly the same all over the
globe. But the amount of incom-
ing sunlight is greater in the
tropics than in high latitudes.
As a consequence, air and water
warmed in the tropics must
move toward the poles. Part of
the energy received from the

28

sun is thus used to carry the
excess heat absorbed in low
latitudes to high latitudes where
it can be re-radiated. The
amount of heat transported across
the parallels of 30° is 10 to 20%
of the total incoming radiation,
but the mechanical work in-
volved is less than 1%.

Heat Engines

The situation can be thought
of as if the sea and the atmos-
phere were interlinked heat
engines of very low efficiency.
These engines do mechanical
work against friction by carry-
ing the working fluids, sea water
and air, from the "firebox" of
the tropics to the radiation-
cooled "condenser" of the polar
regions. The circulation of the
working fluids is manifest in the
winds of the air and the cur-
rents of the sea. In the atmos-
phere, it takes place through
the coupling of rotary current
patterns of all possible shapes
and sizes. These include the
trade-wind cells of ocean-wide
dimensions, the large-scale high-
and low-pressure areas of mid-
latitudes, the wavelike jet
stream, hurricanes, tornadoes,
tiny whirls and vortices. In the
sea, major units of the circula-
tion include the Gulf Stream
and the Kuroshio, the fast mov-
ing equatorial currents and the
sluggish currents of the abyssal
depths. These circulation pat-
terns are partly unstable, and
this shows itself to those of us
who live in mid-latitudes as the
radical changes in weather with
which we are all familiar. In
low latitudes over the ocean
the instability produces the ter-
rifying hurricanes of the wes-
tern Pacific and of our own east
coast.

Dr. Revelle is director of the
Scripps Institution of Ocean-
ography, University of Cal-
ifornia.

The behavior of the inter-
linked heat engines of the sea
and the atmosphere is profound-
ly influenced by four facts: First
is their peculiar shape; they are
essentially two thin sheets
wrapped around a sphere; sec-
ond, the sphere is rotating; the
lower layers of air are dragged
along by the rotation, and the
movements of both the sea and
the air are largely determined
by the forces generated by the
rotation ( at a height above our
heads of several hundred miles
there is a transition to a zone
where the sparse atoms of gas
no longer move around the
earth's axis) ; third, the ocean
is not a continuous sheet like
the atmosphere, but is broken
up by the relatively dry areas
we call continents; fourth, like
an invisible pousse cafe, the
atmosphere is stratified in thin
layers that do not mix readily
with each other and each of
these layers has to a consider-
able extent a separate behavior
of its own. The same is true of
the ocean but with the marked
difference that while the tem-
peratures of the different layers
of the atmosphere are alterna-
tively lower and higher as we
go upward, the temperature of
the ocean decreases continuous-
ly nearly to the freezing point
at great depths. It increases
slightly near the bottom be-
cause of the heat coming from
the interior of the earth.

29

The energy needed to drive
the sea-air circulation is only
a small portion of the incoming
solar radiation, but it is still
enormous on a human scale.
The winds of the earth have a
total kinetic energy estimated
to equal seven million atomic
bombs, or more electric power
than all the power plants in the
United States could produce in
a hundred years. This energy
must be replenished every nine
to twelve days because of the
loss by friction between the
winds and the earth's surface.

Although there is a general
agreement about the foregoing
generalizations, our mental
model of the sea-atmosphere
system is so inadequate in many
essentials that meteorologists
are unable to predict anything
very useful for more than a
few days in advance about the
circulation of the atmosphere.

Climatic changes

Even more fundamentally,
we do not know the factors that
determine the average condi-
tions. Consequently, we are
quite unable to forecast changes
in climate. Yet we know that
such changes have occurred in
the relatively recent past. Only
about ten thousand years ago
the earth emerged from a dark
age of snow and ice; less than
five thousand years ago, Green-
land offered a fair and pleasant
habitation for human beings.
Within the last fifty years, the
climate over eastern North
America and northern Europe
has again become slightly
warmer and the Arctic wastes
are perhaps again becoming ac-
cessible to human beings, while
elsewhere prolonged droughts
are destroying the work and
hopes of decades. For the farm-

er, the strategist and the states-
man, an accurate forecast of
climatic change over the next
fifty years would be of immeas-
urable value. But such a fore-
cast is completely beyond our
present ability. Ability to fore-
cast depends on understanding,
and this comes in two interre-
lated ways: by constructing
small models in our heads of
the two great earth fluids, and
by testing and refining these
models through observations.
This second method is one of
the major objectives of the In-
ternational Geophysical Year.
In particular, we are concerned
with measurements in areas
that have never been adequate-
ly explored and of phenomena
that have never been ade-
quately studied.

To increase our understand-
ing of climatic change we can
ask first, what changes have
occurred in the past and how
did they happen? Second, be-
cause a change in climate is es-
sentially a change of average
air temperature, we need to
examine the ways in which the
heat content of the air can vary.
The heat content must be that
required to give a balance be-
tween incoming and outgoing
radiation, hence it can vary if
there is a change in the amount
of incoming radiation from the
sun, in the proportion of sun-
light reflected versus that
absorbed, or in the amount of the
infrared back radiation absorbed
by carbon dioxide, water vapor
and ozone. A lc/( change in the
intensity of the incoming sun-
light or in the amount of sun-
light reflected back to space
would give about a 1° centigrade
change in the average air tem-
perature.

30

The total solar radiation
seems to be remarkably cons-
tant. The most recent contin-
uous observations are those
made at the Lowell Observatory
since 1953. During this period
of sunspot minimum no solar
variations in the blue region of
the spectrum greater than 0.3%
have occurred. Ionospheric ob-
servations show, however, that
ultraviolet components of the
solar radiation are larger dur-
ing periods of sunspot maxima,
and the visual spectrum obser-
vations must therefore be con-
tinued throughout at least one
sunspot cycle before we can
say definitely that solar radi-
ation is virtually constant over
decades.

In contrast to the apparent
constancy of the incoming radi-
ation, the reflectivity of the
earth would appear to be easily
changeable. Clouds, snow and
ice reflect most of the sunlight
that falls on them, whereas the
ocean surface, vegetation and
bare ground are highly absorb-
ing for visible light. At present
about 50 % of the earth's surface
is normally covered with clouds,
while large areas are capped
with snow and ice, particularly
during winter. An average of
35% of the incoming sunlight is
reflected back to space without
being absorbed. The average air
temperature would decrease by
1° centigrade if the reflection
increased to 36% through in-
creased cloudiness or a spread-
ing of the snow and ice-covered
areas.

Dust in the upper air also
scatters and reflects sunlight
before it can reach the ground
and ocean surfaces. After the
explosion of the volcano Kra-

katoa in 1883, the incoming radi-
ation from the sun and sky
decreased by 5 to 10/< for three
years. Changes in the water
vapor, ozone or carbon dioxide
content of the air change the
amount and character of the
infrared absorption. Calcula-
tions indicate that a 25 % change
in the carbon dioxide content
of the air would change the
average air temperature by 1°
centigrade.

The factors affecting the av-
erage air temperature are inter-
related; there are in fact what
electronic engineers call "feed-
back" relationships between
them. These feedback linkages
are both positive and negative.
For example, an increase of air
temperature from whatever
cause would result in a melting
of part of the snow and ice cover
of the earth and a correspond-
ing reduction in the reflection.
Consequently, the amount of
absorbed radiation would in-
crease and the temperature
would rise still further. This is
a positive feedback. Similarly,
an increase of average air
temperature would increase the
evaporation from the oceans,
hence the water vapor content
of the air and absorption of
infrared radiation. The tempera-
ture would not increase without
limit, however, because an in-
crease in evaporation must
eventually result in an increase
of cloudiness as the water vapor
condenses, hence an increase in
the proportion of reflected sun-
light. This is a negative feed-
back. Such complex feedback
linkages tend to hunt or oscil-
late, with time constants de-
termined by the speed of the
different processes involved.

31

Thus far we have been dis-
cussing comparatively small
changes in average air tempera-
ture over the earth. Such
changes may be of great signi-
ficance— it is generally esti-
mated by meteorologists that a
4° drop in average air tempera-
ture would be sufficient to bring
on a new ice age. But with
present meteorological observ-
ing facilities they would be al-
most impossible to measure.
What is observed are local
changes of much greater mag-
nitude. These must be brought
about chiefly by variations in
atmospheric and perhaps ocean-
ic circulation, specifically in the
locations of north-south trans-
port of heat and matter.

For example, the January
mean temperature at Spits-
bergen increased by 24° from
1913 to 1937, whereas during al-
most the same period there was
a 3 to 55 drop in January mean
temperature in the Great Basin
of the western United States.

Because of the complex rela-
tionship between the amounts
of insolation and infrared ab-
sorption on the one hand and
the circulation patterns of
north-south transport on the
other, it is by no means certain
whether an increase of insola-
tion or absorption would bring
on a colder or a warmer climate.

Past Changes

The circulation patterns are
profoundly affected by the dis-
tribution of continents and
oceans, and therefore it is of
great importance to make com-
parative studies of past climatic
changes in the northern and
southern hemispheres, because
of their markedly different pat-
terns of sea and land. Since
changes in the intensity of the

north-south circulation should
have different effects in high
and low latitudes, it is also nec-
essary to attempt to determine
the nature of simultaneous cli-
matic changes in different lati-
tude zones.

The great ice caps of Antarc-
tica and Greenland and the
mountain glaciers throughout
the world are remarkable indi-
cators of climatic change. Dur-
ing periods of warming or
reduced precipitation the gla-
ciers retreat; when the atmos-
phere is cooled or snowfall
increases they thicken and rap-
idly advance. Moreover, the
layers of ice laid down in suc-
cessive years constitute an un-
rivalled record of events on
earth during past millenia.

Many aspects of glaciers will
be studied during the IGY.
Among the most significant
from the standpoint of the heat
and water budget of the earth
will be the thickness of the ice.
This will be measured by the
seismic techniques used in pros-
pecting for oil. Bore holes and
cores will also be taken to study
the frozen record of the past.

Ice caps now cover about 3%
of the earth's surface. A melting
of two feet per year over these
surfaces seems quite possible
from present data. This would
result in a rise of sea level of
about an inch per year or rough-
ly ten feet in one hundred
years. Even such a rise as this
would bring serious consequen-
ces to many thickly populated
coastal areas.

The sediments of the deep
sea floor, like the ice caps, con-
tain a detailed climatic record
extending back over many
thousands of years. For ex-
ample, variations in the num-

32

bers of limy shells of the tiny
animals called foraminifera re-
flect variations in the oceanic
circulation near the surface.
The ratios of oxygen isotopes
in these shells tell us something
about past ocean temperatures.
At least part of the present
temperature differences we can
measure between different lay-
ers in deep sea sediments may
be the result not of heat flow
from the earth's interior but of
warmer temperature of the
deep ocean waters a few hun-
dreds or thousands of years
ago. Studies of these sediments
and their significance for cli-
matic change will be an impor-
tant part of the series of
oceanographic expeditions to be
conducted during the Inter-
national Geophysical Year.

The meteorologist and the
oceanographer can seldom use
that peerless tool of the labora-
tory scientist— controlled exper-
iment. As substitutes for ex-
periment they must attempt to
make comparative investiga-
tions of the behavior of the
earth fluids under different con-
ditions. For this reason a major
part of the IGY meterological
program will be focussed on
comparisons between the south-
ern and the northern hemis-
pheres.

Because the earth is closer to
the sun in January than in July,
the southern hemisphere re-
ceives about 6/f more radiation
in summer than does the nor-
thern. The geometry of the two
hemispheres is also quite dif-
ferent. In the north, the Polar
Sea with its thin, cracked skin
of ice is surrounded by conti-
nents; in the south a continent
nearly twice the size of the

United States, having an ice
covered surface two miles above
sea level, lies at the pole
and is surrounded by the great
southern ocean. This high cen-
tral plateau, sheathed in dark-
ness for six months each year,
is a focal point for inward-
circling storms and outward
surges of cold air. The weather
conditions in the Antarctic are
nearly incredible; for example,
wind velocities at Adelie Land
have averaged 110 miles per
hour for a day, more than sixty
miles per hour for a month and
about forty miles per hour for
an entire year. The American
IGY party now maintaining a
vigil at the South Pole have
already recorded temperatures
below-100° F. with 15 to 20 knot
winds.

As is well known, the testing
of large atomic weapons pro-
duces considerable amounts of
radioactive substances, some of
which decay rather slowly. A
large part of the radioactive
material produced by atomic
weapons tests is injected into
upper strata of the air and can
be used by meteorologists as a
tracer of atmospheric move-
ments, for example to determine
the rate at which the air at
different levels is carried from
the northern to the southern
hemisphere and vice versa, and
the rate of mixing between the
upper and the lower atmos-
phere. An important IGY ob-
jective will be world-wide
measurements of these artificial-
ly radioactive substances.

Gains and Losses

A slight excess or deficit in
the input of solar energy over
the output of infrared radiation
from the earth may cause large
changes in weather and, if long

33

continued, in climate. At pres-
ent we are unable to determine
whether such differences be-
tween income and outgo exist.
Here the earth satellite pro-
gram shows great promise; one
of the first satellites will carry
relatively simple equipment for
measuring the difference be-
tween the amounts of incoming
and outgoing radiation at all
points over its path. Later satel-
lite experiments will include
actual mapping of the earth's
cloud and snow cover, allowing
accurate and continuous meas-
urements of the amount of
sunlight reflected from the
earth, a quantity that can at
present only be rather crudely
estimated.

A change in average air tem-
perature represents, of course,
a gain or loss of heat from the
air, but it need not represent
a gain or loss from the ocean-
atmosphere-glacier system of
the earth. On the other hand, an
excess of heat could be stored
for long periods on the earth
without much change in the
temperature of the lower air.
There are two great mechan-
isms for this: one is the melting
of ice caps, the other is the
heating of the deep waters of
the ocean. The latter has by far
the larger capacity. The energy
required to melt all the ice in
Antarctica is equivalent to
about two and a half years'
supply from the sun at the pres-
ent rate of 175,000 calories per
square centimeter each year.
This same amount of energy
would raise the average tem-
perature of the ocean by only a
little more than 1° C. (On the
other hand, the melting of ice
caps would be somewhat more
obvious to everyone, since it

would result in a rise of sea
level by at least 200 feet, and
the consquent destruction of
most of the world's largest
cities!)

Because of the great heat
capacity of the ocean, many
meteorologists and oceanogra-
phers now believe that climatic
changes lasting over decades or
centuries may be intimately re-
lated to changes in the circula-
tion of the deep sea. Effective
techniques for studying this
circulation have become avail-
able only in the last few years,
and it is little understood. We
know that cold water sinks to
great depths from the surface
in high latitudes, moves slowly
toward the equator and perhaps
across it, and returns by an un-
known path to the starting
point. The time required for the
round trip is not known; it may
be measured in decades or mil-
lenia. Nor do we know whether
the circulation is steady or
intermittent like the flushing of
water in a bowl.

One of the major enterprises
of the International Geophysi-
cal Year will be a series of great
oceanographic expeditions, con-
ducted by seventy ships belong-
ing to many countries. Their
principal objective will be to
obtain a comprehensive picture
of the temperature and other
properties of the deep sea
waters, and to make direct and
indirect measurements of their
motions.

The Earth and Man

President Eisenhower has said
that water is rapidly becoming
our most critical natural re-
source. During the last few
years, serious attempts have
been made to develop inexpen-

34

sive machines for converting
sea water into fresh water. The
fact is, of course, that nature
herself operates a most effective
distillation system. Nearly one-
third of all the energy of sun-
light falling on the sea surface
is utilized in converting sea
water to fresh water by evap-
oration. The immense quantity
of solar power used in this way
is several thousand times all
the power produced by our
industrial society from hydro-
electric power and the burning
of coal, oil, and natural gas.

The total quantity of water
evaporated, if all of it fell on
the surface of the land and was
uniformly distributed, would
result in an average rainfall of
over one hundred inches a year.
Evidently the trouble with the
natural distillation process is
not the quantity of fresh water
produced, but rather that na-
ture's pipe lines are badly
placed. Too much water moves
to some areas and not enough
to others; moreover, the valve
system seems to be capriciously
managed. Sometimes the dis-
charge is too great, bringing
floods, while at other lines there
is only a trickle and droughts
occur.

Can anything be done about
this faulty distribution system?

The quantity of solar energy
used in driving the engine of
the sea and the atmosphere is
so great compared to any of the
energy sources under man's
control that it would seem im-
possible for us to affect weather
or climate materially by any
human action. Yet, a close look
shows there may be some things
we could do. Many of the pro-
cesses in the atmosphere are
metastable: a slight action may

initiate a very large-scale pro-
cess. We might learn how to
regulate climate if we could
find the right lever to pull.

One may predict that with
the coming of greater under-
standing, promising methods for
control of weather and climate
will be found. The average re-
flectivity of the ground surface
over the large areas might be
reduced, for example, by rapid
melting of the snow cover, thus
increasing the percentage of
sunlight absorbed. On the other
hand, it might be possible to
shut off some of the sun's radi-
ation before it reaches the
earth's surface, for example, by
injecting a small amount of ab-
sorbing or reflecting substances
into the upper atmosphere.

Great Experiment

During our lifetime we may
be witnessing an example of
one way in which human ac-
tions can affect weather and
climate. Since the beginning of
the industrial revolution, an
amount of carbon dioxide equal
to about 12 % of the total al-
ready present in the atmosphere
has been produced by the burn-
ing of coal, oil, and natural gas.
The ability of the ocean to
absorb carbon dioxide is very
great and probably most of the
amount added to the atmos-
phere during the last century
has gone into the sea. During
the next hundred years, how-
ever, the increasing use of fossil
fuels in our world-wide indus-
trial civilization should result
in the production of about 1700
billion tons of carbon dioxide —
70% of the amount now in the
atmosphere. Because of the
rapid increase in the production
rate, the fraction of the added
carbon dioxide absorbed by the

35

ocean will be lessened and an
increase of perhaps 20^ in at-
mospheric carbon dioxide can
be expected. The effect of such
an increase is not easy to pre-
dict, but there is some theoreti-
cal reason to believe that it
could result in a warming of
the lower atmosphere by sev-
eral degrees. Thus, by consum-
ing within a few generations
the fossil fuels laid down in
sedimentary rocks over many
hundreds of millions of years,

we are conducting, more or less
in spite of ourselves, a great
geophysical experiment. It is of
vital importance to keep ac-
curate records of this experi-
ment in order to increase our
understanding of the mechan-
isms controlling climate. With
this in mind, careful measure-
ments will be made during the
IGY of the carbon dioxide con-
tent of the atmosphere, and
studies will be initiated to refine
our estimates of the absorption
of. carbon dioxide in the sea.

Jin fflemonam

WlTHIN a single week during August oceanography suddenly
lost its two greatest leaders. Carl-Gustav Rossby died on August
19 in Stockholm and Harold Ulrich Sverdrup passed away equally
unexpected in Oslo on August 21. Professor Rossby had been as-
sociated with the Institution from its beginning. He worked here
on many occasions during the summer and for longer periods.
Most physical oceanographers in this country were at one time
among his students. Professor Sverdrup was the director of our
sister laboratory, the Scripps Institution of Oceanography, during
the period 1936-46. He has visited Woods Hole on many occasions
and while fewer of us have actually studied under his direction,
we all are entirely familiar with his classical text book, "The
Oceans." Both men were actively engaged in research and teaching
at the time of their death.

C. O'D. I.

Currents and Tides

Among distinguished visitors
in recent months were: U.S.S.R.,
Professor L. Zenkevitch; Great
Britain, Dr. K. F. Bowden, Dr.
G. E. R. Deacon, Dr. Ronald
Fraser, Professor A. C. Hardy,
Dr. M. N. Hill, Dr. N. B. Mar-
shall, Dr. John B. Tait; West
Germany, Dr. G. Bbhnecke, Dr.
Gunther Dietrich, Dr. Hans
Walden; Denmark, Dr. Anton
Bruun, Professor E. Steemann
Nielsen; Japan, Mr. Bunkichi
Imayoshi, Dr. Y. Miyake, Mr.

Haruyuki Koyama, Mr. Ichiji
Yoshitani; Norway, Professor H.
Mosby; Argentina, Cdr. L. R. A.
Capurro; United States, Dr.
Roger Revelle, Dr. Norris W.
Rakestraw, Dr. John E. Tyler;
British Columbia, Dr. John D.
Strickland; Netherlands, Mr. P.
Santema, Dr. J. Th. Thijsse;
India, Dr. B. D. Laroia; New
Zealand, Dr. R. Culver, Dr. F/
H. Sagar; Australia, Professor
W. Stephenson; Bermuda, Dr.
W. H. Sutclirre, Jr.; Greece, Mr.
Athanasios Hatzikakidis.

36

The

WOODS HOLE OCEANOGRAPHIC INSTITUTION
in the

INTERNATIONAL GEOPHYSICAL
YEAR

The International Geophysi-
cal Year (IGY) is a cooperative
program of research in the
earth sciences, an outgrowth of
previous international Polar
Year Surveys. The U. S. pro-
gram is coordinated on the in-
ternational level by the National
Academy of Sciences-National
Research Council, while work-
ing groups direct the research
in each particular field. Mr.
Iselin, our director, is the cur-
rent chairman of the inter-
national work group in ocean-
ography.

Within this country, the Na-
tional Academy of Sciences has
set up a National Committee for
the IGY to distribute funds
provided by direct congressional
appropriation to support the
programs of the U. S. partici-
pants.

Approximately one-sixth of
the national budget of $1,870,000
in oceanography has been grant-
ed to this Institution for the
support of programs being car-
ried out in cooperation with the
Lamont Geological Observa-
tory, Texas Agricultural and
Mechanical College, the Scripps
Institution of Oceanography, the
University of Washington, and
several Government facilities.

Deep Currents

One of the major U.S. pro-
grams is the study of those deep

currents which move the water
masses below 6,000 feet. As the
chart on page 2 of this issue
shows, a considerable amount
of the work in the Atlantic
Ocean already has been ac-
complished and it is a source of
satisfaction that the R.V. Craw-
ford (Captain David F. Casiles)
has been able to do so much
work in such a short time. This
is, of course, due to the hard
work and cooperation among
the scientific parties, the ships'
officers and crews, and our
shore facilities.

By the end of this year we
shall have finished profiles of
salinity, temperature, and ox-
ygen along parallels eight de-
grees apart over most of the
Atlantic Ocean with only a few
left to be done next year. Three
of the eleven profiles have been
made by our friends on the
R.R.S. Discovery II (Captain
S.S.F. Dalgleish). Altogether,
this program represents an
enormous amount of work. Ob-
servations from the sea surface
to the ocean bottom have been
obtained 80 miles apart in deep
water and at closer intervals near
the coasts. One of the more inter-
esting items has been the fact
that the Crawford returned with
worked up data which, in the
past, was mostly left to be done
after the return of a cruise. This
has become possible not only by
dint of hard work but also due

37

to the development of Karl E.
Schleicher's shipboard salin-
ometer. Formerly, thousands of
water samples were brought
back to be titrated in the lab-
oratory at Woods Hole.

In the South Atlantic the
work is duplicating that done
by the German Meteor Expedi-
tion, 1925-27, to detect any long-
term changes which may have
taken place in thirty years. Mr.
F. C. Fuglister was in charge
of the work in the South
Atlantic. Mr. W. G. Metcalf is
chief scientist during the pres-
ent work along the 40th and
16th parallels while Messrs.
L. V. Worthington; F. C. Fuglis-
ter and H. Stommel have taken
part in the Discovery II cruises.

In addition to the hydro-
graphic observations, large
water samples have been and
are being collected for analysis
of geochemical properties. This
work is being supervised by
Drs. V. T. Bowen and B. H.
Ketchum. For the study of
radioactive elements in sea
water it was necessary to ob-
tain much larger water samples
than those taken by Nansen
bottles. A 55-gallon collapsible
rubber sampler was developed
by Dr. Bowen and already has
seen much service.

The study and analyses of
these samples will provide in-
formation on the naturally oc-
curring radioactive elements
and the distribution and mixing
of fallout material from wea-
pons tests. The former is espec-
ially important to establish a
baseline to which future meas-
urements may be related. The
radioactive isotopes to be stud-
ied are: carbon, hydrogen, an-
timony, cerium, cesium, pro-
methium, and strontium, while

analysis will also be made for
oxygen, nitrates, ammonia,
phosphate, total nitrogen, phos-
phorus, and chlorine. It is hoped
that unique data on the distri-
bution of certain radioactive
fission products in the Atlantic
may be obtained.

CQ2

A continuously recording car-
bon dioxide gas analyzer has
been purchased. The instrument
has been adapted for use on
board ship and in our new DC-3
aircraft (Captain Norman Gin-
grass) by Drs. Bowen and
Leahy. As Dr. Revelle has
pointed out in this issue, it is
vitally necessary to obtain in-
formation on the level and dis-
tribution of carbon dioxide in
the ocean and in the atmosphere.
Previous measurements have
been spotty. The continuously
recording apparatus will make
it possible to study problems of
a detailed and restricted nature,
for instance, the rate of ex-
change of CO2 between the
ocean and the atmosphere. In
conjunction with some of the
radioactive studies we may also
obtain important information
on convection and vertical mix-
ing in the upper layers of the
ocean.

Indian Ocean

In 1958 the Atlantis (Captain
W. Scott Bray) will sail to the
South Atlantic to make a north-
south section along the South
American coast and some short
sections at 12° South and 20°
South to fill in gaps in impor-
tant areas not covered by the
Crawford. She will then make
the final southernmost profile
at 32 3 South before sailing for
the Indian Ocean to work with

38

the Vema of the Lament Geo-
logical Observatory for joint geo-
physical and oceanographic ob-
servations. (Another joint cruise
with the R.R.S Discovery II is
reported on page 13 of this
issue.)

Arctic Observations

Another extensive area of
operations during the IGY will
be the Arctic Ocean, where
observers camp on the ice island
"T-3" and a large floe of ice
north of Point Barrow. Main-
tained by the U. S. Air Force
for the IGY program the two
camps are occupied by about
twenty scientists and military
personnel. The Institution's sci-
entists sent to this area working
under the leadership of Mr. W.
G. Metcalf make deep hydro-
graphic observations from the
ice. By occupying both available
stations and taking advantage
of the drift of the ice, a series
of short hydrographic sections
probably can be completed.
Such observations will contrib-
ute significantly to the present
rudimentary oceanographic data
from that area.

As a part of a general acous-
tical study of the ocean, fre-
quency calibrated measure-
ments of sea sounds in the arctic
basin -will be made under the
direction of Dr. J. B. Hersey.
The two major contributors to
the noise level in arctic waters
are marine animals and the
sounds of moving sea ice. Work-
ing under Dr. F. Birch of the
Dunbar Geophysical Laboratory
of Harvard University, another
group will measure the heat
flow from the earth in this area.
Such measurements have been
made previously at sea by drop-
ping a long temperature sensi-

tive probe into the bottom
sediments and measuring the
difference in temperature be-
tween successive thermal ele-
ments in the probe. The knowl-
edge gained by such measure-
ments is of major importance
to our understanding of the
earth as a whole. Prior attempts
from shipboard have been
hampered by the difficulty of
hovering in position over the
probe long enough to allow the
thermal elements to come into
equilibrium with the bottom
sediments. By making the meas-
urements from relatively sta-
tionary ice in the Arctic it will
be possible to wait long enough
for the equilibrium to develop.
Besides furnishing data from a
new area, the observations may
also provide a check for ship-
board measurements which had
relied on a theoretical tempera-
ture equilibrium curve.

The major significance of the
IGY for the Institution is proba-
bly not the increase in available
funds for oceanographic re-
search, but in the concept of the
program itself. It is now pos-
sible to visualize an extension
of cooperative research beyond
the period of the IGY, conceiv-
ably with continuing financial
support resulting from the ac-
tivities of this special period.
The Special Committee on Oce-
anographic Research (SCOR) of
the International Council of
Scientific Unions has been
formed as an organizational
nucleus for such continuing re-
search effort. Long-range, large-
scale plans were made during
the August SCOR meetings at
Woods Hole, heralding a new
phase of international coopera-
tion in oceanographic research.

39

The PBY amphibian plane is
no longer with us. Too old for
service she has been replaced
by an R4D, U. S. Navy plane
given to the Institution on loan.
An R4D is the Navy designation
for a DC-3.

With typical abandon the In-
stitution's scientists have drilled
holes in the sides and bottom of
the plane for instruments, cam-
eras, etc. Captain Norman Gin-
grass is her commander.

Yes, we know the instrument
on the front cover is not a Nan-
sen bottle. It is an Ekman
bottle used by the Bermuda
Biological Station on board the
Caryn. The gentleman stand-
ing on the cruel sea is its direc-
tor, Dr. Wm. H. Sutcliffe, Jr.

The R.R.S. Discovery II vis-
ited Woods Hole from Novem-
ber 8 to 16 while making the
sections along the 24th and 32nd
parallel.

40

ML

LIBRARY

WH 17YV ~

ASSOCIATES

OF THE

WOODS HOLE OCEANOGRAPHIC INSTITUTION

NOEL B. McLEAN, President

JOHN A. GIFFORD, Secretary

RONALD A. VEEDER, Executive Assistant

EXECUTIVE COMMITTEE

CHARLES F. ADAMS JOHN A. GIFFORD

BENJAMIN H. ALTON PAUL HAMMOND

WINSLOW CARLTON NOEL B. McLEAN

RACHEL L. CARSON HENRY S. MORGAN

W. VAN ALAN CLARK MALCOLM S. PARK

PRINCE S. CROWELL GERARD SWOPE, JR.

F. HAROLD DANIELS THOMAS J. WATSON, JR.

JAMES H. WICKERSHAM

INDUSTRIAL COMMITTEE

Chairman: CHARLES F. ADAMS

President, Raytheon Manufacturing Company

ROBERT M. AKIN. JR.
F. M. BUNDY
M. C. GALE
MILLARD G. GAMBLE
PAUL HAMMOND

F. L. LaQUE

LOUIS E. MARRON
WILLIAM T. SCHWENDLER

D. D. STROHMEIER
MILES F. YORK

President, Hudson Wire Company

President, Groton Pew Fisheries

President, Monarch Edsel Company, Inc.

President, Esso Shipping Company

President, The Hammond, Kennedy & Legg

Company

Vice President, The International Nickel
Company, Inc.

Chairman, Coastal Oil Company

Executive Vice President, Grumman Aircraft
Engineering Corporation

Vice President, Bethlehem Steel Company
President, Atlantic Mutual Insurance Company

RAYMOND STEVENS, President

C. O'D. ISELIN, Director
EDWIN D. BROOKS, JR., Treasurer

Contents

Articles

SYNOPTIC STUDIES IN OCEANOGRAPHY 3

Columbus O'D. Iselin

THE FINGER 13

G. E. R. Deacon

THERMAL CIRCULATION 19

George Veronis

SUN, SEA AND AIR 27

Roger Revelle

THE INSTITUTION IN THE IGY 37

Features

ASSOCIATES' NEWS 18

GIFTS AND GRANTS 16

CURRENTS AND TIDES 16

A BREACHING HUMPBACK 17

Published by

WOODS HOLE OCEANOGRAPHIC INSTITUTION

WOODS HOLE, MASSACHUSETTS