Oceanography

HMS Challenger (1872-1876)

• British ship sent out to sea 

  • Oceanography origin story 

  • Seeked to look at properties of water (depth, organisms, stations)

  • Discovered Marianas Trench in the western Pacific

When did people start travelling by sea?

• Anatomically modern humans (Homo Sapiens) appear in fossil record of East Africa about 200,000 years ago 

• Agriculture and civilization wouldn't appear until about 10,000 years ago (roughly the start of the Neolithic)

Pesse canoe

• Oldest surviving boat about 10,000 years old, discovered in the Netherlands 

  • Wasn't really traveled by sea, this boat was probably for hunting on creeks and marshes 

  • Still used in Sepik River, Papua New Guinea

Wallace Line

• Separates the “tigers and elephants” (Indonesia) from the “wallabies and kangaroos” (Australia) 

• Humans left traces of being on land that requires open water crossing the wallace line 

• Evidence of hominins on Luzon island in Philippines as early as 700,000 years ago appears to require a much earlier open water crossing (Pre-Homo Sapians) 

4500 to 2500 BC

• Evidence from anthropology and archaeology suggest that the people who explored and populated the Pacific and Indian ocean basins migrated from Asia to Taiwan and then Luzon in the Philippines 

• The polynesians were the first known people to undertake regular, long distance voyages

  • They build elaborate canoes to take these voyages and developed navigational systems to move between islands 

    • Ex. Hokule’a, launched 1975 

Colonization

• Around 10,000 islands in the western pacific 

• Colonized new guinea around 30,000 years ago 

• Colonized Philippines around 20,000 years ago 

• Colonized Hawaii - the farthest away from any land masses around 1500 years ago 

How do you find your way to a distant landfall?

GPS and charts (maps)

Polynesian navigation

• Reflection of islands in the clouds 

• Followed birds - ex. Frigate and terns: dawn/dusk patterns 

• Stars (celestial navigation)

• Swells: large waves, distant from source of wind 

• Stick charts - gets memorized by the navigator, not brought on the boat

900 - 700 BC

• The Greeks and the Phoenicians had traveled, traded, and colonized around the Mediterranean 

• The Greeks called the Mediterranean “Thlassa” and thought it was surrounded by land, which in turn was surrounded by an endlessly circling river called “Oceanus”

AD 150: Eratosthenes (276 - 195 BC)

• Invented the study of geography and an early system of latitude and longitude

• First person to calculate the tilt of the Earth’s axis

• He calculated the Earth’s circumference without ever leaving Egypt

Ptolemy’s - Map of the Greco-ROman World (AD 150)

• Geocentric solar system guy (he was wrong) 

• His map of the world included latitude and longitude

900 AD

• Vikings explore and colonize Iceland, Greenland, and Newfoundland

• They are also among the first to use the North Star to determine their latitude 

• Latitude = east to west 

• Longitude = north to south 

• Each degree of latitude is divided into 60 minutes 

• A minute of latitude is equal to one nautical mile 

Captain James Cook - 1750 AD

• Led to colonization of Australia by British and the first contact between Hawaiians and Europeans 

  • Extensive Scientific Investigations 

  • Arctic to Antarctic 

  • Mapping of the Pacific Ocean

  • Depth soundings 

  • Winds and currents

  • Subsurface temperatures

  • Biological samplings 

  • General geography of pacific and atlantic 

When was Darwin’s Expedition?

Darwin's expedition on the Beagle in 1832-1836

What observation stations were set up on the Challenger?

• Depth 

• Sample of the bottom 

• A sample of the bottom water for chemical and physical examinations 

• The bottom temperature was recorded 

• Bottom fauna

• Fauna of the surface and of intermediate depths 

• Samples of sea water at different depths 

Which theory did the Challenger dispell?

• Azoic’s theory

• Challenger discovered 4700 new species of marine animals and plants

Famous institutions for ocean science

• Marine Biological Laboratory

• Scripps Institutions of Oceanography

• Woods Hole Oceanographic Institution (WHOI)

Tools to study water

• Plankton tow (bongo) 

• The Conductivity Temperature Depth (CTD) for pressure 

• Ponar Grab 

• Dredges 

• Ocean drilling 

• Multibeam SONAR for imaging the bottom 

• Submersibles

What is the top of the ocean called?

Water column = Pelagic

What is the bottom of the ocean called?

Sediments = Benthos