Oceanography - intro

What percent of the Earth’s surface is covered in oceans?

70.8

oceans are Earth’s _________ habitat

largest

__% of water is in oceans

97

where is the rest of water on Earth?

Groundwater > Ice & Snow > Lakes > Atmosphere > Swamps > Rivers > Biological Water

Biggest and deepest ocean

Pacific

Most dominant ocean in atmospheric conditions

Atlantic

Warmest ocean

Indian

Smallest and shallowest ocean

Arctic

“Newest” (described) ocean

Southern

list the oceans from largest to smallest

Pacific > Atlantic > Indian > Arctic > Southern

global ocean

there is only one world ocean

the Pacific is the world’s largest ____________ feature

geographic

the Atlantic plays a crucial role in global ________ and ______

climate and trade

where is the largest mountain range on Earth

the Atlantic (mid-Atlantic ridge)

why is the Indian ocean less productive?

it’s warmer — increased temperature decreases biomass

how thick is the sea ice in the Arctic?

up to a few meters

what is another name for the Southern ocean?

Antarctic

what makes seas different than oceans?

smaller, shallower, saltier; usually enclosed by land and directly connected to an ocean

we used to think there were seven seas, now we know that there are way more than ____ seas, bays, etc

100

Ancient 7 seas (Greek)

Adriatic

Arabian

Black

Caspian

Mediterranean

Persian

Red

Deepest ocean

Mariana Trench

the average ocean depth is ______ meters, while the average continental elevation is ___

3,682 vs 840

the deepest ocean trench is ________ meters, and the highest mountain is ______

11,022 vs 8,850

Early exploration of the ocean

people used boats to seek new fishing grounds for food → trade and interaction between cultures

Pacific Navigators

No human evolution on Pacific islands — populated by voyagers traveling 1000s of miles across open ocean to widely scattered islands.

Phoenicians

first people from the Western Hemisphere to develop navigation arts — explored seas and circumnavigated Africa

Greek Pytheas

Sailed northward (toward North Star) to determine latitude

Eratosthenes determined Earth’s circumference

Claudius Ptolemy

Produced fairly accurate world map around

Tried to correct Eratosthenes’s estimated circumference and failed bad, leading to Columbus thinking he landed in Asia

When were Arabs the dominant navigators in the Mediterranean

The Middle Ages

Arabs traded extensively with East Africa, India, and Southeast Asia. They learned to use ___________________ for travel

Indian Ocean monsoon winds

What did the Vikings find when they explored North Atlantic Ocean in the Middle Ages

They found and settled Iceland and Greenland, and designated part of eastern Canada

Erik “the Red” Thorvaldson

'discovered’ Greenland

Bjarni Herjólfsson

first to find Newfoundland, Greenland (previously called Vinland)

The Age of Discovery in Europe (1492–1522)

Search for new Eastern trade routes by sea

Prince Henry (Portugal) sought trade routes around __________

Africa (Bartholomeu Diaz rounded southern tip of Africa in 1486)

Europeans explored North and South America:

Columbus was financed by the Spanish to find new trade routes to Asia

Myth about Columbus

Widely credited with discovering North America, but never set foot on the continent

Italian Giovanni Caboto (John Cabot)

landed on northeastern coast of North America

Vasco Nuñez de Balboa

attempted land crossing at Isthmus of Panama

Spaniard Ferdinand Magellan

Began circumnavigation of the globe in 1519, killed on a Pacific Island in 1521

Juan Sebastian del Caño

completed Ferdinand Magellan’s global circumnavigation in 1522

Voyages paved the way for the Spanish to…

steal gold from the Incas and Mayas

Spain’s maritime dominance ended when…

England defeated the Spanish Armada in 1588

After they defeated the Spanish Armada in 1588, the English wanted to retain maritime superiority, so Captain James Cook (1728–1779) undertook three scientific voyages:

HMS Endeavour, Resolution, and Adventure — mapped many islands in the Pacific and systematically measured ocean characteristics, creating a marine chronograph (longitude)

high-technology Oceanography tools available today

Sonar

Robotics

Computers

Satellites

NOAA

National Oceanographic and Atmospheric Administration

What is Oceanography

Scientific, interdisciplinary study of all aspects of the marine environment: geology, astronomy, geography, biology, chemistry, and physics