Chapter 2 Chapter 2 Knowing the Ocean WorldKnowing the Ocean World

Earth Is an Ocean World

The relative amount of water in various locations _______________________. More than _______of the water lies in the ocean. Of all water at Earth’s surface, ice on land contains about 1.7%, groundwater 0.8%, rivers and lakes 0.007%, and the atmosphere 0.001%.

Earth Is an Ocean World

The _________depth of the ocean is________ as great as average land elevation. Note the extent of the____________, Earth’s most prominent single feature.

Marine Science (or oceanography) integrates many different types of science:

•__________________– the study of Earth’s crust and composition

•___________________– the study of waves, currents, and climate prediction.

•______________________– the study of the nature and distribution of marine organisms.

•_____________________– the study of the dissolved gases and solids in the ocean.

•_____________________– the design and construction of structures used in or on the ocean.

Marine Scientists Use the Logic of Science to Study the

OceanWhat methods do marine scientists use to obtain and interpret data?

Scientific methods are not a simple set of steps followed by every researcher to answer every question. However, some questions can be answered by using the following method:

Ask a____________

Form a working__________

Observe or__________

Form theories and laws

Fig. 1-5, p. 6

Curiosity

A question arises about an event or situation: Why and how does this happen? Why are things this way?

Stepped Art

TheoryPatterns emerge. If one or more of the relationships hold, the hypothesis becomes a theory, an explanation for the observations that is accepted by most researchers.

ExperimentsTests are undertaken in nature or in the laboratory. These tests permit manipulating and controlling the conditions under which observations are made.

HypothesisA tentative explanation is proposed. Controlled experiments are planned to prove or disprove potential cause-and-effect relationships. A good hypothesis can predict future occurrences under similar circumstances.

Observations, measurements

Our senses are brought to bear: What is happening? Under what circumstances? When? How does it operate? Does there appear to be a dependable cause-and-effect relationship at work?

Law

Theories can evolve into larger constructs: laws. Laws explain events in nature that occur with unvarying uni-formity under identical conditions. Laws summarize experimental observations.

_______________________

Understanding the Ocean Began with Voyaging for Trade and Exploration

Voyaging on water was important to many early civilizations. The Egyptians, Cretans, and Phoenicians were all skille__________________________and maps that record details of the ocean d sailors. Since then and especially now - winds and currents, islands and their resources, and methodology for navigation.

_________________________, in Egypt, was founded in the third century B.C. This library stored information on every area of human endeavor. Many scholars came to live there and discuss scientific ideas_________________of Cyrene was the second _____________at Alexandria. He was the first to calculate the__________________________. He also invented a system of longitude and latitude.The _______________________________were

invented at the Library at Alexandria.

Library of Alexandria, Egypt

All that was left after the ____________burned it to the ground in 415

AD.

Newly rebuilt Library (2002) and scientific conference center.

Eratosthenes’sCalculation of the circumference of Earth

A diagram showing Eratosthenes’s technique for calculating the circumference of Earth.

As described in the text, he used simple geometric reasoning based on the assumptions that Earth is spherical and that the sun is very far away. Using this method, he was able to discover the circumference of Earth to within __________of its true value. 300 years later __________“improved “ on this but used flawed data – his estimate was___________– which led to Columbus ___________________when he really reached the Americas

Accurate to within__________________?

Latitude and Longitude

(LEFT) A third century B.C. chart showing the system of latitude and longitude developed by Eratosthenes.

(RIGHT) Diagrams showing the calculation of lines of

latitude and longitude.

Ocean Seafarers Colonized Distant Islands

(Right) The Polynesian Triangle.

Ancestors of the Polynesians spread from Southeast Asia or Indonesia to New Guinea and the Philippines by about __________________years ago.

The mid-Pacific islands have been colonized for about 2,500 years, but the explosive dispersion that led to the settlement of___________ occurred about___________________.

The Polynesian colonization's are an example of knowledge of oceans and marine science used to colonize a vast number of islands.

“Red Arrows” show a possible direction and order of settlement.

The Vikings800 – 1300 AD ?

Viking Raiders using __________pillaged European countries prompting a _________________against the Vikings. They _____________colonizing Iceland, Greenland, and Newfoundland by the year 1000 AD. Long before Christopher Columbus was born!

Chinese Contributions

Chinese navigators (____________) set out in the 1400s to explore the Indian Ocean, Indonesia, Africa and the Atlantic. Their huge ships were laden with gifts designed to________________________________. The Chinese made significant contributions to ocean voyaging:

The_______________– essential in rough seas ____________________________– prevented sinking________________with _________________on multiple masts made sailing easier

The Age of Discovery

Europeans explored the world by sea during the Renaissance.

__________________________________– Explorers under his patronage compiled detailed charts and explored the west coast

of Africa. Established a ___________________________________________________.

_________________to aid in ocean navigation

Christopher Columbus 1490’s – Although he never saw the mainland of North America, his _________________explorers to

follow. Christopher Columbus did not discover North America, and he did not sail around the world, he estimated the Earth’s

circumference as______________________.

Ferdinand Magellan 1522 AD– Although Magellan died en route, the small surviving portion of his

crew_________________________. This proved to the world there was a ______________________________, and that you

could sail around it

Magellan Expedition

The journey of the Magellan expedition, the first voyage around the world. Only 18 out of 260 sailors managed to return after three years of dangerous travel.

Voyaging Combined with Science to Advance Ocean Studies

James Cook, a commander in the British Royal Navy, is credited with leading voyages that____________________________. Some of the accomplishments of James Cook and his scientists include:

Captain James Cook was perhaps the first ocean observer ____________________to be considered

a____________________

•Verification of calculations of ____________ made earlier by Sir Edmund Halley

•Charting of New Zealand and the Great Barrier Reef, Tonga and Easter Islands – 1768 AD – but__________________________________

Where in the World are you??Celestial Navigation

Latitude and Longitude

To accurately navigate, you need to know where you are at all times, Latitude and Longitude

The North Star is directly above the North Pole, and the Equator is exactly 900 degrees from there

-

so

– Use a simple protractor – measure

the_________________________________– and that is your Latitude –

at least in the Northern Hemisphere.

Where in the World are you??John Harrison –

Cabinet Maker and maker of watches

To accurately navigate, you need to know where you are at all times, Latitude and Longitude

The world is round – like a circle – it has 3600. There are 24 hours in

a day – so 3600 / 24 = 150Now_________________________, and at high noon, a ___________________is

directly under it. = 00 Long.

Wherever you are, ___________of high noon, ________________(150) it takes

to get to 12 o’clock noon in Greenwich time. Say 5 hours, so 5 * 150 = 750 Longitude. The problem was _____________of the

day were not___________.For a prize, John Harrison introduced the “Number Four” which was ___________enough – That is how John Cook ____________the

Ocean Blue

Voyaging Combined with Science to Advance Ocean Studies

James Cook, a commander in the British Royal Navy, is credited with leading voyages that greatly contributed to scientific oceanography. Some of the accomplishments of James Cook and his scientists include:

Captain James Cook was perhaps the first ocean observer _______________to be considered

a_________________.

•____________marine life, land plants and animals

•_________data concerning the ocean floor and_____________________

Scientific Sampling – not as easy as it sounds

• Sediment samples – both geological and biological– Early devices were___________________– Later came the scoop– Then the______________– Recent by very expensive_________________________

• Water samples – both chemical and biological– Problem with_________________– Early - upside cans lowered, then righted– Later________________________

• Depth readings- “soundings”– Early - ___________on__________– difficult in deep waters and rough seas –

very time consuming – ______________________– Later sonic waves – the German Expedition _____________used this method

successfully – _______________• Ocean Floor Geology

– Early – beach or shallow water, or by luck with scoop– Later coring devices penetrate the floor, the __________the ocean the

more_______________

The First Scientific Expeditions Were Undertaken by Governments

• The United States Exploring Expedition, led by_________________, launched in 1838 was an early naval and scientific expedition.

– This expedition incorporated the __________________since the large Chinese Voyage of Adm. Zheng He in 1431

– This was a broad exploration event which also explored portions of the continental United States –such as the Oregon Territory, and lasted 4 years

– One topic of investigation was to see if the__________, and _____________were at the Poles! This myth was___________

Wilkes is most famous for confirming _____________________________.

The First Scientific Expeditions Were Undertaken by Governments

• First Benjamin Franklin (1769) and his cousin Tim Folger, then US Navy Officer _________________1840’s plotted, and charted the ocean’s____________________

• Franklin published a basic “Gulf Stream Map” explaining why sailors could travel faster in the direction of (down – current)

• Maury collected data from the Navy’s Depot of Charts and Instruments and sensed a __________________of these currents. Many voyagers realized ___________ ____________________, thus making oceanic voyaging more efficient due to this .

• Maury’s significant contribution to Oceanic Expeditions was his book “The Physical Geography of the Seas” which explained his theories, published in 1855.

M.F.M. - or Mathew Fontaine Maury is considered by many to be the

___________________________________

The First Scientific Expeditions Were Undertaken by Governments

• (BELOW) HMS Challenger expedition of 1872-1876 was the first oceanic expedition dedicated to pure scientific research.

• Samples obtained for scientific study include:

– Biologic evidence at different depths and temperatures (discovered _________– _______________– Temperature– ____________– Current direction and velocity– ___________– Sediments

•A 50 volume report was produced, and is still used extensively today.

•Positive financial “spin-offs” proved Exploration can be a good investment!

The HMS Challenger expedition remains as

the _____________________

_ oceanographic expedition to this

day

• The quest for scientific knowledge for purely scientific reasons is always a good thing.

• Sometimes it is used for other reasons as well. Alfred Mahan (1892) used the history of previous conflicts, coupled with the new data collected and analyzed through Marine Science Exploration, and prepared a very ______________ entitled “The

Influence of Sea Power Upon History”. This clear and practical analysis of _________________influenced the

strategies used in the last centuries_________________________.

_______________= is the means by which a nation _____________________capacity into the ocean

Voyages for Science in the Twentieth Century• Polar Exploration – explorers reached both

the North and South poles in the twentieth century– Norwegian explorer Fridtjof Nansen used his

small but extrememly sturdy ship the Fram to get “____________” in the North Polar Sea.

– The __________Fram “_____________

This proved there was no_________________

Others include:

North Pole -Peary, Henson, Anderson (with Nuclear Submarine), and now modern subs that rise through the ice.

South Pole – Amundsen (on the Fram) Scott, Wilson

The “Fram”

Voyages for Science in the Twentieth Century

The ____________Expedition – 1925 – the first expedition to use modern optical and electronic equipment for oceanographic investigation

(right) ______________________ ________________of the seafloor by beaming sound waves to the bottom and measuring the time

required for the sound waves to bounce back to the ship.

If the round-trip travel time and wave velocity are known, distance to the bottom can be calculated. This technique was first used on

a large scale by the German research vessel ____________in

the 1920s.

Voyages for Science in the Twentieth Century

HMS Challenger 2 1951A new ship named after the first Challenger

Discovered the _______________known to man – named it the “________________________”

______________ – a blimp-like bathyscaphe which descended into the ____________________area of the __________Trench on a later voyage

Glomar Challenger 1968 Samples obtained by scientists on this drilling ship provided _________________for seafloor spreading and _________________

20th Century Voyages Contributed to Oceanographic Knowledge

More Exploration Ships•JOIDES Resolution 1985 drilling

•R / V Chikyu 2007 drilling operated by IODP (_____________________________)

The Rise of Oceanographic InstitutionsWith all the new scientific data being obtained, it makes since that large “study centers” would emerge

___________– Japan Marine Science and Technology Center, home of the two deepest diving

submersibles. A major contributor to the IODP program

Woods Hole Oceanographic Institution , associated with_________, located on Cape Cod, Massachusetts._________________Institution of Oceanography, associated with the__________________________, located in La Jolla, CALamont-Doherty Earth Observatory of_______________________

Along with many US Govt. agencies – including the US Navy, and the National Oceanic and Atmospheric

Administration (NOAA)

Today – and the SatellitesThe National Aeronautic and Space Administration NASA

Modern day satellites now constantly record information about the earth and it oceans, and

transmit these data to researchers, some of these are:TOPEX / Poseidon 1992 - monitors ________________accurate to within 1

cm (½ inch)

Jason 1 2001 - monitors

global________________

SEASTAR 1997 - color scanner of the oceans,

measures______________, a measure of _____________

AQUA, TERRA, AURA, PARASOL, and CloudSat 2002 - a team of satellites designed

to measure Earths_________________

GPS - Global Positioning System – a group (constellation) of 24 satellites that team up with Earth born receivers that will calculate your latitude and longitude. This has

____________________________worldwide!!

End of Chapter 2

With all the progress, and International co-operation on exploring and discovering the Worlds Oceans - I am sure Alexander the Great and all the scholars of the Library

of Alexandria would be proud !

Chapter in Perspective

In this chapter you learned that science is a process of asking and answering questions. Decisions are made based on observable information, not on preconceived ideas or submission to authority. There is no “absolute truth” in science – explanations of natural phenomena will vary as our powers of observation change. The scientific process depends on an open mind, the collection of information, consistent experimentation, and the assumption that nature “plays fair” – that is, that the rules governing natural processes don’t capriciously change.

Science and exploration have gone hand in hand. Voyaging for necessity evolved into voyaging for scientific geographical discovery. The transition to scientific oceanography was complete when the Challenger Report was completed in 1895. The rise of the great oceanographic institutions quickly followed, and those institutions and their funding agencies today mark our path into the future.

In the next chapter you will learn about our place in the universe and about the origin of Earth and the ocean. Earth is about 4.6 billion years old (that’s 4,600 million years). The ocean formed early in Earth’s history, and life followed almost immediately thereafter. Earth is density stratified – that is, its inner layers are heavier than its outer layers. Indeed, the origin and interaction of those layers occupy our attention for the next few chapters.

Look For The Following Key Ideas in Chapter 1

The world ocean may be considered as a single entity with temporary partitions. It covers about 71% of Earth’s surface.

Marine science, or oceanography, is the process of discovering unifying principles in data obtained from the ocean.

Science is the process of asking questions about the observable world and then testing the answers to those questions. The external world, not internal conviction, is the testing ground for scientific beliefs.

The ocean did not prevent humans from occupying nearly every place on Earth that could sustain them.

The origins of marine science lie in voyaging – traveling on the ocean for a purpose. Technological advances made during voyaging and later marine exploration led to the rise of scientific oceanography.

Earth’s shape and circumference were accurately estimated around 230 B.C. at the Library of Alexandria, Egypt. The use of latitude and longitude for positioning and navigation also began there.

Key Ideas Continued… Christopher Columbus did not discover North America, and he did not sail

around the world.

Captain James Cook, Royal Navy, was perhaps the first ocean observer careful enough to be considered a marine scientist.

The Challenger expedition was the first purely scientific voyage of oceanic exploration.

Polar Studies greatly advanced marine science at the beginning of the twentieth century.

Nearly all research is conducted not by individuals but by teams of specialists working in large, nationally funded oceanographic or military institutions.

The tools of modern oceanography include satellites, manned remotely controlled vehicles, and computer modeling.