HISTORICAL OCEANOGRAPHY
Around 200 B.C., Eratosthenes
calculated the circumference of the earth with a unique experiment. His estimate of 40,000 km is very close to
the 40,032 km accepted today.
Starting in 1522 Magellan's crew
circumnavigates the world. Magellan was killed in the Philippines.
An early map of the world shows a
surprising resemblance to present day maps.
An impediment to early exploration of the oceans was the ability to
determine latitude and longitude, particularly longitude.
Latitude can be determined by the angle between
the horizon and the North Star. The North Star essentially remains fixed in position.
Longitude is a function of time. Since a circle
is 360 degrees and earth rotates once every 24 hours, the earth rotates through
15 degrees of longitude every hour.
In 1760, John Harrison invented a third generation of a seagoing chronometer which was reliable, but quite
large. A fourth generation chronometer
finally allowed reliable and practical determination of longitude.
One of the earliest maps of the Gulf Stream
was published by Benjamin Franklin in 1769.
The five year cruise of the BEAGLE began
in 1831. The Chief Scientist was a naturalist named Charles Darwin. It was on this cruise that he
formulated his ideas concerning evolution. The crucial observations were made
in the Galapagos Islands.
In 1872 The HMS CHALLENGER set sail
from England for a three and one-half year around the world.The CHALLENGER was
the first major oceanographic expedition from 1872-1876 to systematically
collect data from a large part of the worlds oceans under the direction of the
chief scientist Sir Charles Wyville Thomson (no 'p').
The expedition took 3 1/2 years and covered over 65,000 nm. They occupied 362
stations and took the first soundings over 12,000' using a 200 lb. weight.
They used hemp lines for towing nets and dredges as well as the
soundings.
At each station they took soundings and measured
the temperature of the surface and the bottom and fairly frequently the
intermediate layers as well. Usually they made one or more hauls with the
dredge or trawl and towed nets and measured surface currents.
They found that at a depth of about 3000 fms the
sediments contained little or no globigerina ooze (the carbonate compensation
depth). They collected manganese nodules.
They discovered the Puerto Rico Trench when their
self-registering thermometers came up fractured from the great pressure at a
station 90 miles north of St. Thomas. In a crossing from the Cape Verde Islands
to Brazil they found the deepest temperatures change from 36 degrees C on the
east to 34 degrees C in the west. Nares, the captain, speculated that the
Atlantic was divided down the middle by a bank or series of banks from Dolphin
Rise in the north to Ascension Island or even St. Helena in the south. At their
furthest station south, 153, they measured the surface temperature at 29.5
degrees C and a reading of 32 degrees C at 300 fms and 32.8 degrees C at 500
fms. This apparent temperature inversion is the sinking of the Antarctic
Intermediate Water.
A 50 volume series of reports was eventually
produced which described over 4000 new species. A complete set is in the TAMU
library.
1888 - The Marine Biological Laboratory is founded in Woods Hole,
Massachusetts.
1893 - Nansen sets adrift in the FRAM
to prove that the Arctic Ocean is entirely ice
covered with no continent under the ice.
1912 - Alfred Wegner begins a series of
lectures on continental drift, a radically new concept at the time.
1912 - Scripps Institution of Oceanography
becomes affiliated with the University of California. SIO is located in La Jolla, California, just
north of San Diego.
1949 - Texas A&M Department of Oceanography and Lamont-Doherty
Geological Observatory (in Palisades, New York) are founded.
1960 - The bathyscaphe TRIESTE
descends to 10,915m in the Marianas Trench
1965 - Scripps Institution of Oceanography develops a new type of ship
called FLIP or Floating Laboratory and
Instrument Platform. It is towed to the working area where one end is flooded
and it starts to tip up, finally reaching
its full, upright position. In this position
it has remarkable vertical stability.
1968 - Monster Bouys are located
across the Pacific to collect oceanographic and meteorological data.
1968 - The GLOMAR CHALLENGER starts
operations for the Deep-Sea Drilling Project. Over the years the OPD (Ocean
Drilling Project) has drilled many sites.
Many different drill bits are used under
various conditions. The rig that sits
on the bottom has a re-entry cone that
allows a site to be revisited and re-entered if necessary. This program is an
international effort and the U.S. budget alone is about $40m. At present, the
program is operated from the Texas A&M campus with offices on the West
Campus.
1977 - ALVIN, the only U.S. manned,
scientific deep submersible (at that time), locates and documents deep-sea
hydrothermal vents in the eastern tropical Pacific.
1978 - SEASAT, a dedicated oceanographic
satellite, is launched.
Satellites allow the measurement of global sea surface temperature (SST)
over a period of about two weeks, so that fall
SST and summer SST can be subtracted to
get seasonal differences.
Satellites also allow the measurement
of surface
chlorophyll concentrations to
be measured over similar periods.
1985 - JOIDES RESOLUTION replaces
the GLOMAR CHALLENGER as the flagship of the Ocean Drilling Program.
1985 - JASON finds and documents the
wreck of the TITANIC. Bob Ballard, the designer, goes on to explore other
wrecks such as the BISMARK and the LUSITANIA.
1992 - TOPEX is launched to measure sea
surface altimetry.
Since the turn of the century many major oceanographic expeditions have
been mounted, but the costs have escalated and alternative modes of data
collection are being explored. TODAY a large vessel (250 ft) costs about
$18,000/day while a smaller vessel such as the TAMU GYRE 170 ft) runs about
$8,000/day
Specialized vessels are used for special applications at added expense.
These include ships like the JOIDES RESOLUTION for deep-sea drilling (more in
the geological section) and ALVIN for manned exploration of the deep-sea floor.
It requires a dedicated surface support vessel and can cost a total of
$20,000/day. ALVIN and the RESOLUTION are operated by consortia.
Satellites are very expensive also and collect near-surface data only, but
can cover large sections of the oceans in very short periods of time.
Additional information on satellites can be obtained from the home page for Goddard Space Center,
the SeaWiFS
Project Home Page,or the TOPEX/Poseidon
Home Page.
There have also been major changes in sources of funding -
in the early days of oceanographic exploration
funding came from governments such as in the case of the CHALLENGER, but they
were few in number. Most was funded by private sources and was necessarily
limited in scope.
With the onset of W.W.II, it became very clear
that the United States had insufficient knowledge of the seas, the tides and
coastal processes. The Navy began to fund a significant amount of research.
In 1950 the National Science Foundation was
formed and began to fund oceanographic research. Presently its total level of
support is approximately $3.16B (FY96), while the research appropriation is
$2.254B.
Other funding comes from sources such as Minerals
Management Services, the National Marine Fisheries Service (NOAA) and the
Department of Energy. As awareness of the complex interactions of the oceans,
the atmosphere and the land increase, so will the diversity of potential
funding sources.
Job opportunities - in the past a major destination for oceanographers was
academia, but this has changed with more openings in the government (strongly
influenced by the environmental position of the administration in power) and
the private sector (consulting firms, oil companies etc.).
Increased competition for both positions and
funding have resulted from the relatively young age of oceanography as compared
to, say, chemistry (just reaching a stable age distribution) and the historical
trend for us to clone ourselves through our graduate students.
The number of Ph.D.'s produced yearly
in oceanography rose sharply early in the 60's and 70's and then leveled out
somewhat. The cumulative number of Ph.D.'s
in oceanography has shown an almost exponential increase.
A "family" tree will
illustrate part of this dilemma.
Important Terms: Magellan, latitude,
longitude, Charles Darwin, , Nansen, FRAM, Wegner
Summary Time Line for 1825-2000
Top of Page
