Lesson Outline

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Lesson Outline
I. 19th Century Contributions
II. The Challenger Expedition
III. The 20th Century
IV. Modern Oceanography
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Christian Ehrenberg (17951876)
Ehrenberg, a Professor of Medicine in Berlin,
Germany, and an amateur rock collector, examined
small particles of rocks under a microscope.
Looking at his rock samples under high
magnification, he found fossil evidence of small
plants and animals. He reasoned that if these
plants and animals were in the rock, and the rock
came from the sea floor, then the small plants
and animals might also be present in seawater.
He then examined a sample of concentrated sea
water under a microscope, and found live animals
similar to the fossils in the rock samples.
We now call this whole group of microscopic
plants and animals plankton.
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Johann Forchhammer (17941865)
Forchhammer was a geologist working on the
minerals in rocks that would dissolve in water.
He found seven minerals in rocks that would
dissolve easily in water, the same seven minerals
that make up the salt in salt water.
Forchhammers work showed that the salt in
seawater originated from the land.
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Matthew Maury (18061873)
Another man who made a significant contribution
to the knowledge of the sea was Matthew Maury.
As the director of the Navys Bureau of Charts
and Instruments, Maury studied the huge amount of
information contained in old ships log books
stored under his care.
Maury later represented the U.S. at the Brussels
Maritime Conference which convened to standardize
how oceanographers record weather and current
observations.
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Matthew Maury (18061873)
In 1847, Maury assembled all this information
into a chart of the wind and surface currents of
the North Atlantic.
Historians often refer to Maury as the Father of
Physical Oceanography for his work.
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Charles Darwin (1809-1882)
Remembered more for his theory of evolution than
for his work in oceanography, Darwin spent five
years on a British survey vessel observing coral
reefs and atolls.
Following the expedition, he proposed an
important theory on the formation of atolls and
coral reefs.
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Darwins Bulldog
Thomas Huxley (18251895 ) was a naturalist who
asked to analyze bottom samples from a survey
vessel, in some of which he found what appeared
to be a very primitive form of life.
He named it Bathybius Haeckelli, and even went so
far as to speculate how Bathybius reproduced.
As it turned out, there was no such animal as
Bathybius, it was an artifact. When the bottom
sample was preserved with alcohol, the alcohol
reacted with chemicals in the sample and produced
the jelly mass right there in the jar.
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Depth of No Life
In the 1840s, the British biologist Edward
Forbes was studying the zonation of life in the
sea. He observed that in shallow water, the sea
floor contained numerous kinds of sea life. But
as the water became deeper, the numbers of marine
life became less.
Forbes concluded that at a depth of 300 fathoms
(1800 feet) the water was too cold, the pressure
too great, and the environment too hostile for
life to exist.
In fact, Forbes was wrong. There is no such
thing as too deep for marine life to exist.
Life occurs at the bottom of the deepest ocean
trenches, almost 7 miles deep!
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John and James Ross
At the same time Forbes was proposing a depth of
zero animal life, two Canadian scientists, Sir
John Ross and his nephew, Sir James Clark Ross,
were bringing up samples of marine life from the
sea floor at far below the depth Forbes was
saying life ceased to exist.
Working off the coast of North America with a
bottom grab that had steel jaws and could be
lowered down on a cable to bring up a sample of
the bottom and its marine life, they were
collecting samples teeming with animal life, like
starfish, worms, clams, and other bottom-dwelling
animals.
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The Challenger Expedition
To settle the dispute in the scientific community
between Forbes on eastern side of the Atlantic
the Rosses on the western side, the British Royal
Society funded an ambitious oceanographic survey.

A steam and sail-powered naval ship, the H.M.S.
Challenger, was converted into the worlds first
oceanographic research vessel for the voyage.
The scientific party was composed of six
scientists under the direction of Wyville
Thompson.
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The Challenger Expedition
The ship left England in 1872, and returned in
1876, sampling the waters and marine life of
parts of the Atlantic and Pacific Oceans. They
took an enormous number of samples, from sea
water to bottom mud, from microscopic plankton to
fish and birds.
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The Challenger Expedition
Once back in England, these samples were sent to
experts in each field for analysis. It took some
15 years for these samples to be studied and
written up. Then one of the biologists from the
scientific party, John Murray, put all this
information together and had it published.
When finished, the Challenger Reports totaled
nearly 300,000 pages bound in 50 volumes. For
the next 40 years, this work was to be the
bible of oceanography.
History often dates the start of modern
oceanography with the Challenger expedition.
Many of the sampling techniques still in use
today were developed on this expedition.
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The Challenger Expedition
The major findings of the Challenger Expedition
include

• the first systematic plot of currents and
  temperatures in the ocean

• a map of bottom deposits that has not been
  changed much by more recent studies

• an outline of the main contours of the ocean
  basins

• the discovery of the mid-Atlantic Ridge

• the then record 26,900 feet (8,200 meters)
  Challenger Deep in the Mariana Trench

• the discovery of 715 new genera and 4,717 new
  species of ocean life forms

• the discovery of prodigious life forms even at
  great depths in the ocean!

According to the Environmental News Network
Daily News.
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Nansen and the Voyage of the Fram
An important expedition at the end of the 19th
century was led by Fridtjof Nansen (18611930) of
Norway.
In the 1890s, Nansen was interested in Arctic
exploration. At that time it was thought that
there was land under the North Pole, but Nansen
was convinced otherwise.
To prove this, he had the Fram custom built with
a rounded hull so that when it became frozen in
the pack ice, it would slip up on top of the
forming ice and not be crushed as the ice later
shifted.
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Nansen and the Voyage of the Fram
In 1893, Nansen and his crew of twelve, with a
five years supply of provisions, sailed up to the
edge of the pack ice and allowed the ship to be
frozen into the ice.
While frozen into the ice, Nansen took twelve
samples of the Arctic waters beneath the ice,
measured the depths of the Arctic Sea, and
developed a sampling device later called the
Nansen Bottle.
The Fram then drifted with the ice pack for three
years, but never made it to the North Pole, one
of Nansens goals.
The Fram finally broke free of the ice off the
coast of Greenland, proving that the Arctic Sea
was all ice which drifted with the polar winds.
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The 20th Century
In 1905, Walfred Ekman, a Scandinavian physicist,
used Nansens information about the movements of
polar ice sheets and developed a mathematical
model describing the response of surface water
flows to winds.
This led the way for much of our physical
oceanography in the early 20th century.
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The Meteor Expedition
In 1925, scientists aboard the German ship Meteor
were the first to use of the echo sounder for
measuring the depth of the sea floor.
With the echo sounder, a pulse of sound is
transmitted downward to bounce off the sea floor
and return to a special receiver set in the
bottom of the ship.
Since the speed of sound in water is about 1500
m/s, the time interval between the transmission
and reception of the sound pulse could be
converted to a depth measurement.
The best thing about the echo sounder is that it
could be used while the ship was in motion,
giving continuous readings that were recorded on
a fathometer.
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Modern Oceanography
Knowledge of the ocean increased rapidly in the
latter half of the 20th-century for a variety of
reasons

• The funding of civilian scientists interested in
  basic research with naval applications.

• The establishment of academic institutions
  specifically for advanced oceanographic research.

• The founding of the National Oceanic and
  Atmospheric Administration (NOAA).

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Deep-Sea Drilling Programs
The Deep Sea Drilling Project (19681975) was
conducted to confirm a compelling theory about
the history of the ocean floor.
The 122-meter drilling ship, the Glomar
Challenger, was designed to drill into the sea
floor more than 6,000 meters below the sea
surface and recovering samples of sea floor
sediments.
In 1985, the JOIDES Resolution was built to take
over the deep-sea drilling functions as part of
the International Ocean Drilling Program, a joint
oceanographic research effort between the United
States, France, the United Kingdom, Germany, and
Japan.
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Technological Advances
Deep-sea submersibles, both manned and unmanned,
have provided researchers with stunning
discoveries from the deepest and most remote
regions of the sea floor.
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Telemetry
At the sea surface, real-time data from sensors
mounted on buoys and ocean platforms are
transmitted to researchers at coastal and inland
research facilities.
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Space Technology
Satellites in space carry special instruments
that can measure the sea surface height, water
temperature, and the concentration of organic
material in the upper layer of the ocean.
These remote sensing data are then transmitted in
real time back to laboratories on earth and
disseminated quickly via the Internet.
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Computer Technology
In the laboratory, super fast computers have
enabled scientists to formulate mathematical
models of complex ocean processes and test them
through computer simulation.
Many of these modelers input real data into their
models to try to predict the course of future
events, such as the weather patterns resulting
from an El Niño event or the coastal response to
the passage of a hurricane.