Oceanographic Explorations

Topic of the lesson:
OCEANOGRAPHIC EXPLORATIONS
OceanographicOceanographic
ExplorationsExplorations
By
Prof.A. Balasubramanian
Centre for Advanced Studies in Earth Science
University of Mysore, India

Table of ContentsTable of Contents

 After attending this module, the user would be able to
understand the history behind oceanographic
explorations, the stages of development of oceanic
investigations, and the scholars who have contributed at
various stages.
 It will also be possible to comprehend the current trends
in the science of oceanography in terms of on-going
expeditions, technological improvements and the
involvement made by various countries.
ObjectivesObjectives

IntroductionIntroduction
 Throughout the subject of world history, sailing has been
instrumental in the development of human civilization. Sailing
afforded the humanity with greater mobility than travel over
land. Sailing was done for trade, for transport, for warfare,
and for fishing. The earliest representation of a ship under
sail, appeared on a painted disc found in Kuwait, dating back
to the late 5th millennium BC. The first boats are presumed
to have been originated from dugout canoes, developed
independently by various stone age populations. These were
used for coastal fishing and travel.
(…Contd)

 The earliest seaworthy boats might have been developed
as early as 45,000 years ago. Oceanographic explorations
and expeditions have been conducted by people for
several centuries. The birth of the oceanographic
navigation, dates back to several centuries. They all
contributed to the science of oceans.
 Understanding the sequences of Oceanographic
explorations is a very lengthy aspect. A few of the notable
contributions made in the historical past are highlighted
in this lesson.
IntroductionIntroduction

 Maritime history is the study of human activity at sea. It
covers a broad thematic element of history that often
uses a global approach, although national and regional
histories remain predominant.
 As an academic subject, it often crosses the boundaries
of standard disciplines, focusing on understanding
humankind's various relationships to the oceans, seas,
and major waterways of the globe.
Maritime HistoryMaritime History
(…Contd)

 The concepts of Nautical history records and interprets the
past events involving ships, shipping, navigation, and seafarers.
 Many parts of their observations and understandings are taken
for scientific studies or subsequent explorations and
navigations.
 Oceanographic explorations were started way back around
4000 BC.
 The details available on various visible forms and oral-cum-
written records of sailors and explorers made the subject to
grow as a separate science.
Maritime HistoryMaritime History

 It was during the period around 4500 BC, the Ocean
Diving habit was started by the ancient people.
 This was the time when, coastal cultures like those seen
in Greece and China begun with people diving into the
sea to gather food and engage themselves in commerce.
 In this period only, the ancient Egyptians developed their
first sailing vessels.
Ancient Explorations around 4000 BCAncient Explorations around 4000 BC
(…Contd)

 These vessels were probably used for sailing in the
eastern Mediterranean sea and near the mouth of the
Nile river.
 It was also recorded around 1000 BC, the Greek poet
Homer mentions about fishermen diving upto 30
meters by holding on to a heavy rock.
Ancient Explorations around 4000 BCAncient Explorations around 4000 BC

 In search of tin and other natural resources, the
ancient Phoenicians develop typical sea routes
around the Mediterranean sea , into the Red Sea
and into the Indian Ocean.
 They also reached England by sailing along the
western European coast.
First Sea Routes around 600 BCFirst Sea Routes around 600 BC
(…Contd)

 Treasure Diving was continued throughout these
periods.
 Diving for treasure created many wars between
the Persians and the Greeks.
 Around 414 BC the Diving was used in warfare.
 The Greek historian Thucydides writes about diving
used in warfare in his narration of the siege of
Syracuse.
First Sea Routes around 600 BCFirst Sea Routes around 600 BC

First Crude Diving Bell DesignFirst Crude Diving Bell Design
 It was around 360 BC, the Greek philosopher Aristotle
mentions about the use of a sort of crude, air-supply diving
bell.
 Aristotle wrote that "one can allow divers to breathe by
lowering a bronze tank into the water.
 Naturally the container is not filled with water but air,
which constantly assists the submerged man".
 It was around 325 BC, the first use of a Diving Bell was
observed. (…Contd)

 Alexander the Great made use of a crude diving bell to
employ combat divers during the siege of Tyre.
 The diving bell contained colored glass so that the divers
could see through it.
 The divers used the bell to clear debris from the
harbour.
 Alexander himself made several dives with the device to
check on the progress of the work.
First Crude Diving Bell DesignFirst Crude Diving Bell Design

 It was around 325 BC, the Greek astronomer and
geographer, Pytheas, sailed towards north from the
Mediterranean.
 He reached the coast of England.
 He was the first person, on record, who described
about the land of midnight sun and the north of the
Arctic Circle.
 He also developed methods for using the Sun and the
North Star to determine the location of latitudes.
The Voyage of PytheasThe Voyage of Pytheas

 Around 200BC, the Greek astronomer,
Eratosthenes, became the first person to determine
the circumference of the Earth.
 It was a breakthrough in the history of geography.
 He used the angles of shadows and the distance
between Alexandria and Syene to arrive at a value of
40,000 km.
Circumference of the Earth DiscoveredCircumference of the Earth Discovered
(…Contd)

 The actual circumference of the Earth was found to
be 40,032 km.
 The world’s all geographic, earth and atmospheric
sciences got a turning point after these observations.
Circumference of the Earth DiscoveredCircumference of the Earth Discovered

 In the year 150 BC, the Greek astronomer and
geographer, Ptolemy, produced the first map of the
ancient world.
 It was showing the distribution of continents of Europe,
Asia, and Africa as well as the surrounding oceans.
 This early map was one of the first known maps
developed to include the lines of latitude and longitude.
Ptolemy's Map of the WorldPtolemy's Map of the World
(…Contd)

 Around the year 100 BC, Salvage diving operations were
continued around the major shipping ports of the eastern
Mediterranean.
 It was around 200 AD, the First Indicated Use of Goggles
were found from the artworks on Peruvian pottery.
 They have shown the divers wearing goggles and
holding the fish with them.
 Fishery was an important occupation of people from time
immemorial.
Ptolemy's Map of the WorldPtolemy's Map of the World

 It was around 900 AD, the Vikings begun to explore and
colonize the Iceland, Greenland, and Newfoundland.
 They were among the first groups to use the North Star
to determine their latitude.
 In the year 1002, Norse explorer Leif Erikson became
the first European to land in the North America.
Viking Expeditions and Voyage of Leif EriksonViking Expeditions and Voyage of Leif Erikson
(…Contd)

 His voyage took place almost 500 years before that of
the Christopher Columbus.
 He called the new land as Vinland and established a
Norse settlement in what is now seen in the northern
tip of Newfoundland in Canada.
 This paved the way for oceanographic explorations for
territorial ownership, at a later stage.
Viking Expeditions and Voyage of Leif EriksonViking Expeditions and Voyage of Leif Erikson

 Chinese exploration includes exploratory Chinese
travels abroad, on land and by sea, from the 2nd
century BC until the 15th century.
 Before the advent of the Chinese-invented mariner's
compass in the 11th century, the seasonal monsoon
winds controlled Chinese navigation.
ChineseChinese ExplorationExploration
(…Contd)

 In the year 1405, the Chinese made seven voyages
consisting of over 300 ships with a combined crew of
nearly 37,000.
 These voyages were designed to extend the Chinese
influence and impress their neighboring states.
 Their economic pressures back home made them to
put an end to these expensive voyages of the
Chinese.
ChineseChinese ExplorationExploration

 Chinese envoys sailed into the Indian Ocean in the
late 2nd century BC.
 They reportedly reached Kanchipuram, known as
Huangzhi to them.
 During the late 4th and early 5th centuries, Chinese
pilgrims like Faxian, Zhiyan, and Tanwujie, began
travelling by sea to India, bringing back Buddhist
scriptures and sutras to China.
Indian Ocean and beyondIndian Ocean and beyond
(…Contd)

 By the 7th century, as many as 31 recorded Chinese
monks including I Ching managed to reach India the
same way.
 In 674, the private explorer, Daxi Hongtong, was
among the first to end his journey at the southern
tip of the Arabian Peninsula, after travelling through
36 countries west of the South China Sea.
(…Contd)

 Chinese seafaring merchants and diplomats of the
medieval Tang Dynasty (618—907) and Song Dynasty
(960—1279) often sailed into the Indian Ocean after
visiting ports in South East Asia.
 Chinese sailors would travel to Malaya, India, Sri Lanka,
into the Persian Gulf.

 The Spanish explorer Christopher Columbus sets out
on his historic voyage across the Atlantic Ocean in
search of a passage to China and India, in the year 1492.
 Instead, he discovered the North and South America,
which eventually led to the establishment of European
colonization in these newly discovered continents.
Voyages of Columbus and Vasco da GamaVoyages of Columbus and Vasco da Gama
(…Contd)

 Similarly, in the year 1498, they Voyage of Vasco da
Gama made some unique findings.
 The Portuguese explorer, Vasco da Gama, sailed
his ships around the Cape of Good Hope, located on
the southern tip of Africa.
(…Contd)

 He became the first European to reach India by
boat.
 The expedition later returned to Portugal with a
huge valuable cargo of rare spices and valuables.
 This has opened a new dimension in oceanographic
explorations.

 In the year 1519, Ferdinand Magellan and his fleet
departed from Portugal to start a daring voyage of
discovery, in history.
 The fleet became the first to sail around the whole
world.
 Magellan's expedition of 1519–1522 became the first
expedition to sail from the Atlantic Ocean into the
Pacific Ocean.
First Circumnavigation of the WorldFirst Circumnavigation of the World
(…Contd)

 The Magellanic Penguin was named after him, as he
was the first European to note it.
 In March 1505, at the age of 25, Magellan enlisted in
the fleet of 22 ships sent to host D. Francisco de
Almeida as the first viceroy of Portuguese India.
 Although his name does not appear in the chronicles,
it is known that he remained there eight years,
in Goa, Cochin and Quilon.
(…Contd)

 He participated in several battles, including the battle of
Cannanore in 1506, where he was wounded.
 In 1509 he fought in the battle of Diu.
 But unfortunately, Magellan could not live to see the
entire accomplishment.
 He died on the Island of Mactan in the Philippines, in
1521, from the poison arrows sent by the local natives.

 An English mathematician, named William Bourne,
drew up the first known plans for an underwater
boat, in the year 1578.
 These plans called for a leather-covered wooden
frame craft that would be rowed from the inside.
Later, in the year 1620, the First Submarine was
made.
 Dutch physician, Cornelis Drebbel, built the
world's first submarine.
First Plans for a SubmarineFirst Plans for a Submarine
(…Contd)

 The boat was made of wood reinforced with iron and
covered with leather.
 It was a 12 seater submarine in two rows inside.
 They rowed with oars that stick out the sides through
tight fitting leather sleeves to keep the water out.
 Drebbel made several trips in his submarine in the
Thames River, near London , at a depth of about 4 to 5
meters.
First Plans for a SubmarineFirst Plans for a Submarine

 In 1690, the first Air-replenished Diving Bell was
made.
 The English astronomer, Edmund Halley, developed
a diving bell in which the atmosphere in the bell can
be replenished by sending weighted barrels of air
down from the surface.
Voyage of Edmund HalleyVoyage of Edmund Halley
(…Contd)

 In 1698, Edmund Halley made what was called as
the first scientific voyage to study the variation of
the magnetic compass.
 During his voyages, he also made very important
contributions to the understanding of the trade
winds.
Voyage of Edmund HalleyVoyage of Edmund Halley

 In the year 1715, the First Waterproof Suit was
made.
 Chevalier de Beauve, a guard in the French Navy,
developed a waterproof suit with lead shoes.
 Air gets supplied from the surface by two leather
tubes fastened to the helmet.
Waterproof Suit and Diving DevicesWaterproof Suit and Diving Devices
(…Contd)

 In 1715, the First Enclosed Diving Device was made.
 It was Englishman John Lethbridge who developed a
completely enclosed, one-man diving dress.
 The device was made from a reinforced, leather-
covered barrel of air, equipped with a glass porthole
for viewing, and two arm holes with watertight
sleeves.
Waterproof Suit and Diving DevicesWaterproof Suit and Diving Devices

 It was in 1768, Lieutenant James Cook, left the port
of Plymouth, England on a voyage to observe a transit
of the planet of Venus across the Sun.
 During this and other two voyages, he could explore
and map the Pacific Ocean.
 He was the first person to use a chronometer to
accurately determine his longitude at sea surface.
The First Voyage of EndeavourThe First Voyage of Endeavour
(…Contd)

 In the year 1785, the American patriot and inventor,
Benjamin Franklin, writes a lengthy letter to a scientific
colleague in France.
 Known as his Sundry Maritime Observations, the letter
announces the discovery of the Gulf Stream and
touches on a wide range of maritime subjects such as
ship propulsion methods, hull design, and causes of
disasters at sea.
The First Voyage of EndeavourThe First Voyage of Endeavour

 In the year 1800, Robert Fulton, the inventor of the
steamboat, built an early submarine called The Nautilus.
 This cigar-shaped craft was made of wood over iron plates,
and used a horizontal rudder to control the up-and-down
movement of the submarine.
 This system is still in use even today.
 President Thomas Jefferson signs a law establishing the
United States Coast Survey, in 1807.
The NautilusThe Nautilus

 In the year 1831, the English naturalist, Charles Darwin,
departed England aboard in the H.M.S. Beagle.
 The goal of the expedition was to perform a survey of
Patagonia and Tierra del Fuego. Darwin studied the
plants and animals at each new stop.
 He discovered many unique species on the Galapagos
Islands off the coast of Peru in South America.
The Voyage of the H.M.S. BeagleThe Voyage of the H.M.S. Beagle
(…Contd)

 These discoveries led to his groundbreaking theory
of evolution.
 In his book, The Origin of Species, Darwin suggested
that the deep ocean may be a sanctuary for living
fossils.
 In the year 1840, the first Modern Sounding was
done.
(…Contd)

 Sir James Clark Ross conducted the first open ocean
deep-water sounding in 2425 fathoms in the south
Atlantic ocean at Latitude 27 S Longitude 17 W.
 The sounding was made using the traditional method
of lowering a hemp rope over the side of the ship.

 In 1842, Charles Darwin publishes The Structure and
Distribution of Coral Reefs.
 In the year 1843, British naturalist Edward Forbes
stated about his belief that the life cannot exist below
300 fathoms (1800 feet) in the deep sea.
 This declaration made a 20-year debate about the
possible existence of a lifeless zone in the ocean known
as an azoic zone.
Observations of early 19Observations of early 19thth
centurycentury
(…Contd)

 In the year 1849, Coast Survey soundings in support
of Gulf Stream investigations resulted in the
discovery of the continental shelf break and the
continental slope.
 In 1853, Louis F. de Pourtales of the U.S. Coast
Survey found indications of life in depths over 1000
fathoms (6000 feet), inside the deep sea.
(…Contd)
centurycentury

 In 1857, the first Deep Sea Canyon was discovered by
James Alden, a commanding officer of the Coast Survey
Steamer Active, in the center of the Monterey Bay, off
the coast of California.
 It is, now, known as the Monterey Canyon.
 In 1860, the first Chart of the Gulf Stream was published
by the U.S. Coast Survey.
 In 1861, the first U.S. Navy Submarine, Known as the
Alligator, was designed and used.
centurycentury

 In 1872, the most popular Voyage of the H.M.S.
Challenger happened.
 The H.M.S. Challenger sailed from Portsmouth, England
and begun its four-year trip around the world.
 During the voyage, scientists tested the salinity,
temperature and density of the seawater.
 Information was also collected about the ocean
currents, sediment, and meteorology.
Observations of the late 19Observations of the late 19thth
centurycentury
(…Contd)

 The crew discovered underwater mountain chains
and hundreds of species previously unknown.
 This research was eventually consolidated into a fifty-
volume research report known as The Challenger
Report.
 This research formed the basis of modern
oceanography.
Observations of the late 19Observations of the late 19thth
centurycentury

 In 1874, the Sigsbee Sounding Machine was invented. This
new machine became the basic model for wireline sounding
in the deep sea for about 50 years.
 In 1882, the first Oceanographic Research Vessel,
Albatross, was sailed.
 In 1888, the first Modern Electric Submarine, Gymnote,
was designed by the French Navy. This steel-hulled craft
was powered by a 204-cell battery.
Other developmentsOther developments
(…Contd)

 The Marine Survey of the Pacific, made in 1899, by the
Swiss Zoologist Alexander Agassiz , was yet another
milestone.
 In 1912, the Scripps Institute of Oceanography became
affiliated with the University of California.
 The Scripps is one of the world's leading marine research
centers, today.
 In 1914, the first Acoustic Exploration of the Sea Floor was
attempted by the Canadian inventor Reginald Fessenden.
Other developmentsOther developments

 On the 15th
April 1912, the White Star Liner, Titanic,
sunk after striking an iceberg in the North Atlantic
Ocean.
 Over 1500 passengers lost their lives during one of
the worst peacetime maritime disasters in the history
of mankind.
 This tragedy led to a concerted effort to devise an
acoustic means of discovering the objects in the under
water zone, well ahead of a moving vessel.
The Titanic EpisodeThe Titanic Episode
(…Contd)

 In 1985, Dr. Robert Ballard, with the help of a tiny
robotic submarine named, Jason, discovered the
wreck of the Titanic.
 The wreck was found in 3850m of water column at
about 500 km off the coast of Newfoundland in
Canada.
 Titanic was found in two separate pieces.
The Titanic EpisodeThe Titanic Episode

 In 1925, the German vessel, Meteor, sailed around the
Atlantic Ocean and took detailed measurements of the
ocean floor, using modern echo sounding equipment.
 These voyages revealed new information about the
shape and structure of the ocean floor.
 Subsequently, in 1935, the Researchers at the Coast
and Geodetic Survey invented an automatic
telemetering radio sonobuoy.
Mapping the Ocean FloorMapping the Ocean Floor
(…Contd)

 This instrument was considered to be the first offshore
moored telemetering instrument.
 In the year 1937,Geophysicist and oceanographer,
Athelstan Spilhaus, invented the first bathythermograph.
 It was a good measuring device that can continuously
record the ocean water temperature.
 This was a remarkable development, in oceanography, at
that time.
Mapping the Ocean FloorMapping the Ocean Floor

 In 1941, during World War II, the electronic navigation
systems were developed for precision bombing.
 A few years later, the Coast and Geodetic Survey,
conducted its first hydrographic survey using these
systems.
 Research during the war led to many new tools for ocean
exploration, including deep-ocean camera systems, early
magnetometers, sidescan sonar instruments, and early
technology for guiding Remotely Operated Vehicles
(ROVs).
The World War II ResearchThe World War II Research
(…Contd)

 This was a turning point in all modern oceanographic
explorations.
 In 1943, the Aqua-Lung, the first modern scuba system
was designed.
 In 1951, the British ship, Challenger II, bounced the
sound waves off the ocean bottom and located the
sea's deepest point.
 It was subsequently named as the Challenger Deep.
The World War II ResearchThe World War II Research

 It was in 1953, the American geologist, Marie Tharp,
studied the sounding profiles from the Atlantic Ocean
and discovered a rift valley.
 Later studies revealed that it is a continuous rift
valley extending over 40,000 nautical miles along the
ocean floor.
 This discovery provided the most useful evidences for
the newly formed theory of continental drift, known
today as plate tectonics.
Discovery of Mid-Atlantic RidgeDiscovery of Mid-Atlantic Ridge
(…Contd)

 Later in 1961, the Scripps Institution of Oceanography
developed the Deep Tow System.
 This sonar system became the forerunner of all
remotely-operated and unmanned oceanographic
systems, which is used even today.
 In 1963, the first operational multi-beam sounding
system was installed on the USNS Compass Island.
Discovery of Mid-Atlantic RidgeDiscovery of Mid-Atlantic Ridge

 Alvin, a new deep submergence vehicle, was constructed in
1964-by the Woods Hole Oceanographic Institute.
 It was the first U.S. deep diving submersible and the first deep-
sea submersible capable of carrying passengers.
 In 1965, the first Underwater Robotic submarine, Halibut,
which can lower miles of lengths of its cables bearing lights,
cameras, and other gear to spy on enemy armaments and find
the other materials that were once lost on the bottom of the
sea.
Robotic SubmersiblesRobotic Submersibles

 In 1968, the deep sea research vessel, Glomar
Challenger, departed on a 15 year expedition
known as the Deep Sea Drilling Program.
 The ship criss-crossed the entire Mid-Atlantic
Ridge between Africa and South America and took a
lot of core samples.
Deep Sea Drilling ProgramDeep Sea Drilling Program
(…Contd)

 The ages of the samples provided solid evidences
for the theory of seafloor spreading, which late gave
rise to the modern theory of plate tectonics.
 In 1969, the first Long Duration Submersible
Expedition was made off the coast of Palm Beach,
Florida.
 Hydrothermal Vents were discovered in 1977.
Deep Sea Drilling ProgramDeep Sea Drilling Program

 In 1977, the deep-sea submersible, Alvin, was sent to
explore a part of the mid-ocean ridge north of the
Galápagos Islands known as the Galápagos Rift.
 Alvin was following in the tracks of an unmanned vehicle,
towed by the research vessel Knorr, that had detected
unusually high bottom-water temperatures and had
taken photographs of odd white objects among the
underwater lava flows—tantalizing clues about curious,
possibly biological features.
Deep -sea submersible-Deep -sea submersible-AlvinAlvin

 In 1990, a program known as, Argo, was started by
deploying 3,000 robotic probes throughout the world's
oceans to monitor the climate, weather, and sea surface
height.
 It was named after the mythical ship from the story of
Jason and the Argonauts. The last probes were
successfully placed in 2007.
 In 1993, the undersea Laboratory, Aquarius, began its
operation off the coast of Key Largo, Florida.
Argo ProjectArgo Project

 The worldwide mapping of the sea floor from space
was done in 1995.
 In 2010, the Census of Marine Life was Completed.
 This 10 year project involved 2,700 scientists from 80
nations.
 The census revealed what, where, and how much
lives and hides were there in the global oceans.
Seafloor Mapping from SpaceSeafloor Mapping from Space
(…Contd)

 The data is made available in the online directory
that allows anyone to map the global addresses of
species, today.
 In 2012, a Japanese expedition and film crew
captured the first video of a giant live giant squid in
its natural environment.
Seafloor Mapping from SpaceSeafloor Mapping from Space

 Citizens, sailors, and scientists have observed the seas and
oceans for several hundred years
 First from the shore, then from ships and submersibles, and
recently from satellites.
 While carrying out these explorations, scientists and
engineers learned that they could sometimes leave some
sophisticated instruments in the ocean, secured by wires,
buoys, weights, and floats and allow them to systematically
map the ocean floors.
Modern trends in OceanographyModern trends in Oceanography
(…Contd)

 This method is known as the moored observatory.
 This approach has advanced the understanding of the
oceans and their interaction with the Earth and the
atmosphere.
Modern trends in OceanographyModern trends in Oceanography

 In order to understand the ocean, scientists often find that they
have to get themselves or their instruments into very specific
parts of it.
 Traditionally, researchers have used ships to photograph the
depths.
 They used to drop floats and drifters into the currents, and to
collect samples of water, rock, and marine life, for their analysis.
 In recent years, the spectrum of available observing tools has
grown to include human-occupied submersibles, remote-
controlled vehicles, autonomous, and towed robots.
Underwater VehiclesUnderwater Vehicles

 In the year 1957, the Soviet Union successfully
launched its satellite, Sputnik I.
 It was the world's first artificial satellite.
 About the size of a basketball, and weighing only 183
lbs, Sputnik took about 98 minutes to orbit the Earth.
Earth's first Artificial SatelliteEarth's first Artificial Satellite
(…Contd)

 This was the Earth's first artificial satellite ushered in
an age of exploration, not only of space, but of the
Earth's land masses and oceans as well.
 Satellites that detect and observe different
characteristics and features of the Earth's
atmosphere, lands, and oceans are often referred to
as environmental satellites.
Earth's first Artificial SatelliteEarth's first Artificial Satellite

 POES (Polar Operational Environmental Satellites)
maintain an orbital height of about 500 miles(900km)
and take about 100 min to complete an orbit.
 Sea surface-temperature is one important type of
data that these satellites provide.
 Knowing the temperature of ocean water is an
important aspect in oceanography.
Polar Operational Environmental SatellitesPolar Operational Environmental Satellites
(…Contd)

 Temperature changes influence the behaviour of fish.
 It can cause the bleaching of corals, and affects the
weather all along the coast.
 Satellite images of sea-surface temperature also show
patterns of water circulation.
Polar Operational Environmental SatellitesPolar Operational Environmental Satellites

 In addition to temperature, satellites also provide
information about the color of the ocean.
 This allows scientists to detect the presence of algal
blooms, river plumes, and other events.
 Satellite imagery is also being used to map features in
the water, such as coral reefs.
 Sensors such as Landsat-7 and IKONOS provide
detailed information on local areas.
Mapping ocean surface indicatorsMapping ocean surface indicators
(…Contd)

 LANDSAT-7 is part of the LANDSAT program, one of the
longest existing environmental satellite programs.
 Satellites providing environmental imagery are used jointly
with other organizations that receive data from various
sensors.
 For example, marine animals, such as sea turtles and manatees,
can be fitted with transmitters that relay information about
their location.
 Satellites are becoming a standard tool for studying the oceans.
Mapping ocean surface indicatorsMapping ocean surface indicators

 The purpose of the Sea-viewing Wide Field-of-view Sensor
(SeaWiFS) Project is to provide quantitative data on global ocean
bio-optical properties to the Earth science community.
 Subtle changes in ocean color signify various types and quantities
of marine phytoplankton (microscopic marine plants), the
knowledge of which has both scientific and practical applications.
 The SeaWiFS Project will develop and operate a research data
system that will process, calibrate, validate, archive and distribute
data received from an Earth-orbiting ocean color sensor.
Background of the SeaWiFS ProjectBackground of the SeaWiFS Project

 The concentration of microscopic marine plants, called
phytoplankton, can be derived from satellite observation
and quantification of ocean color.
 This is due to the fact that the color in most of the
world's oceans in the visible light region, (wavelengths of
400-700 nm) varies with the concentration of chlorophyll
and other plant pigments present in the water, i.e., the
more phytoplankton present, the greater the
concentration of plant pigments and the greener the
water.
Ocean Color Reflecting Marine BiotaOcean Color Reflecting Marine Biota
(…Contd)

 Since an orbiting sensor can view every square
kilometer of cloud-free ocean every 48 hours, satellite-
acquired ocean color data constitute a valuable tool for
determining the abundance of ocean biota on a global
scale and can be used to assess the ocean's role in the
global carbon cycle and the exchange of other critical
elements and gases between the atmosphere and the
ocean.
Ocean Color Reflecting Marine BiotaOcean Color Reflecting Marine Biota

 GOES satellites provide the kind of continuous monitoring
necessary for intensive data analysis.
 Because GOES satellites stay above a fixed spot on the
surface, they provide a constant vigil for the atmospheric
"triggers" for severe weather conditions such as tornadoes,
flash floods, hail storms, and hurricanes.
 When these conditions develop the GOES satellites are able
to monitor storm development and track their movements.
Geostationary Operational Environmental Satellites (GOES)
(…Contd)

 GOES satellite imagery is also used to estimate rainfall
during the thunderstorms and hurricanes for flash flood
warnings, as well as estimates snowfall accumulations and
overall extent of snow cover.
 Such data help meteorologists issue winter storm
warnings and spring snow melt advisories. Satellite
sensors also detect ice fields and map the movements of
sea and lake ice.
Geostationary Operational Environmental Satellites (GOES)

 The LANDSAT Program provides the longest
continuous space-based record of Earth’s land in
existence.
 Since 1972, LANDSAT satellites have collected
measurements of Earth’s continents and surrounding
coastal regions that have enabled people to study
forests, food production, water and land use,
ecosystems, geology, and more.
The Landsat ProgramThe Landsat Program
(…Contd)

 The long data record allows scientists to evaluate the
dynamic changes caused by both natural processes and
human practices.
 The LANDSAT Program is jointly managed by the U.S.
Geological Survey and NASA.
 Every day, LANDSAT satellites provide essential
information for land managers and policy makers to
support wise decisions about our resources and
environment in the places we live and work.
The Landsat ProgramThe Landsat Program

 The large ocean ecosystems are called as biogeographic
provinces.
 Biogeographic provinces provide useful categories for
comparing and contrasting important ocean processes
such as primary production, carbon flux, and species
distribution and diversity.
 Climatological provinces have been identified using a
priori expert knowledge.
Global Ocean BiomesGlobal Ocean Biomes
(…Contd)

 The global remote sensing data automatically produce the
time and space resolved province distributions.
 Today, 3D mapping of ocean water masses and biomes are
being done in oceanographic analysis.
 Satellite oceanographic products provide an unequalled view
of the global ocean surface allowing us the opportunity to map
important biogeochemical processes in the ocean such as
primary production and carbon export to the deep ocean.
Global Ocean BiomesGlobal Ocean Biomes

 At least 20,000 new biochemical substances from
marine plants and animals have been identified during
the past 30 years, many with unique properties useful
in fighting disease.
 “Biodiscovery” researchers have had success in all
types of ocean environments.
Ocean Exploration and Human HealthOcean Exploration and Human Health
(…Contd)

 A 1991 expedition by the Scripps Institution of
Oceanography’s Paul Jensen and William Fenical resulted in
the discovery of a new marine bacterium, Salinispora tropica,
found in the shallow waters off the Bahamas.
 This bacterium produces compounds that are being
developed as anticancer agents and antibiotics.
 It is related to the land-based Streptomyces genus, the source
of more than half of our current suite of antibiotics.
Ocean Exploration and Human HealthOcean Exploration and Human Health

 Researchers are now looking at the ocean through a new lens:
the science of ”Metagenomics.”
 In the ocean, as on land, thousands of species of tiny microbes
play a key role in nutrient cycles, including the carbon cycle,
and in maintaining Earth’s atmosphere, among other important
functions.
 Metagenomics enables researchers to quickly sequence the
DNA of all microbes in a given sample, in this case seawater,
revealing how microbes function and how they may work in
different environments.
““Metagenomics”Metagenomics”
(…Contd)

 After mapping 64 million base pairs (units of DNA),
thousands of new genes and also variations in the
genetic composition of microbes at different depths
were also discovered.
 Genomes from organisms in the deep ocean had many
“jumping genes,” or pieces of DNA that can move from
one part of the genome to another.
““Metagenomics”Metagenomics”

 Two other U.S. academic and research organizations
operate human-occupied submersibles: the University
of Hawaii has two Pisces submersibles capable of diving
to 2,000 meters (1.2 miles), and Harbor Branch
Oceanographic Institution in Florida has two Johnson
Sea-Link submersibles that can dive to approximately
1,000 meters (0.6 miles).
Human-Occupied SubmersiblesHuman-Occupied Submersibles
(…Contd)

 France and Russia operate HOVs that can dive to a
depth of 6,000 meters (3.7 miles), and Japan’s
Shinkai 6500 is able to dive down 6,500 meters (4.0
miles).
 China is building an HOV that will be able to dive to
7,000 meters (4.3 miles).
Human-Occupied SubmersiblesHuman-Occupied Submersibles

 The Autonomous Benthic Explorer, more commonly
known as ABE, is the first underwater robotic vehicle of
its kind.
 ABE was designed and built at the Woods Hole
Oceanographic Institution (WHOI) in the mid 1990’s.
 ABE weights approximately 1200 pounds and is a little
over 2 meters long.
 ABE's top cruising speed is 2 knots.
Autonomous Benthic ExplorerAutonomous Benthic Explorer
(…Contd)

 As an Autonomous Underwater Vehicle (AUV), ABE
is a true robot, able to move on its own without a
pilot or tether to either ship or submersible.
 This gives ABE the advantage of covering large areas
of underwater terrain.
 ABE was invented to address scientists' frequent need
to monitor underwater areas over long periods of
time.
(…Contd)

 ABE is designed to perform a predetermined set of
maneuvers, take photographs, and collect data and
samples within an area about the size of a city block.
 After accomplishing its mission, ABE “goes to sleep,”
conserving its power supply for months at a time,
allowing for future missions without recharging its
batteries.

 Although ships have been crisscrossing the ocean for
centuries, Earth observations from satellites provided the
first truly global view of the ocean and its processes.
 Recent improvements in satellite communications on ships
are fundamentally changing the nature of sea-going science.
Many oceanographic ships now have Internet connections
through a network known as HiSeasNet.
 With this network, shipboard scientists can work in real
time with their land-based colleagues.
Satellite CommunicationsSatellite Communications

 The International Indian Ocean Expedition (IIOE) resulted
from a cascade of effects.
 The International Geophysical Year of 1957-1958 had
shown the value of coordinated multinational efforts in
ocean science.
 This realization resulted in the International Council of
Scientific Unions (now the International Council for
Science) creating the Scientific Committee on Oceanic
Research (SCOR) to continue to stimulate international
cooperation in ocean sciences.
International Indian Ocean Expedition (IIOE)International Indian Ocean Expedition (IIOE)
(…Contd)

 The International Indian Ocean Expedition (IIOE) was
one of the greatest international, interdisciplinary
oceanographic research efforts.
 It involved forty-six research vessels (under fourteen
different flags) that carried out an unprecedented
number of hydrographic surveys (and repeat surveys)
of the entire Indian Ocean basin from 1960 – 1965.
International Indian Ocean Expedition (IIOE)International Indian Ocean Expedition (IIOE)

 In the last 50 years, since the formation of IIOE, there
have been two fundamental developments in ocean
science.
 The first one is the emergence of new components of
the ocean observing system - most notably remote
sensing and Argo floats.
Emergence of InnovationsEmergence of Innovations
(…Contd)

 The second one is the emergence of ocean modelling
in all its facets - including short-term forecasting,
seasonal predictions and climate projections.
 These developments have revolutionised our
understanding of the global oceans.
 Ocean exploration continues to illuminate details
about Earth processes.
Emergence of InnovationsEmergence of Innovations

 Space-borne radar altimeters are superb tools for
mapping the ocean-surface topography, the hills and
valleys of the sea surface.
 These instruments send a microwave pulse to the
ocean’s surface and determine the time taken by the
waves to return.
 A microwave radiometer corrects any delay that may be
caused by water vapor in the atmosphere.
Ocean altimetryOcean altimetry
(…Contd)

 Combining these data with the precise location of the
spacecraft makes it possible to determine the sea-surface
height very accurately.
 The strength and shape of the returning signal also
provides information on the wind speed and height of
ocean waves.
 These data are used in ocean models to calculate the
speed and direction of ocean currents and the amount and
location of heat stored in the ocean, which, in turn,
reveals the global climatic variations.
Ocean altimetryOcean altimetry

 The Ocean Surface Topography Mission (OSTM) on
the Jason-2 satellite is an international Earth
observation satellite mission that continues the
measurement of sea surface height, which was started
in the year 1992.
 It was followed by the NASA/CNES Jason-1 mission
launched in the year 2001.
Ocean Surface Topography MissionOcean Surface Topography Mission
(…Contd)

 The two previous altimetry missions, TOPEX/Poseidon and
Jason-1, have led to major advances in the science of physical
oceanography and in climate studies.
 Their 15-year record of ocean surface topographic data has
provided the first opportunity to observe and understand the
global change of ocean circulation and sea level.
 The results have improved the understanding of the role of
the ocean in climate change and improved both weather and
climate predictions.
Ocean Surface Topography MissionOcean Surface Topography Mission

 Oceanographic exploration and Maritime history are the two
broad overarching subjects. They include the aspects like fishing,
whaling, international maritime law, naval history, the history of
ships, ship design, shipbuilding, the history of navigation, the
history of the various maritime-related sciences (oceanography,
cartography, hydrography, etc.), sea exploration, maritime
economics and trade, shipping, yachting, seaside resorts, the
history of lighthouses and aids to navigation, maritime themes in
literature, maritime themes in art, the social history of sailors
and passengers and sea-related communities.
ConclusionConclusion
(…Contd)

 Jacques Yves Cousteau, an Oceanographer said “The future
is in the hands of those who explore... and from all the
beauty they discover while crossing perpetually receding
frontiers, they develop for nature and for humankind an
infinite love."
 Oceanographic explorations continue even today in the
form of underwater surveys, expeditions and mission for
sustainable development.
ConclusionConclusion

Oceanographic Explorations

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