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History of Oceanography

History of Oceanography. Why study historic oceanography? . Connected to the world’s overall history Commerce, warfare, resources, weather The oceans have shaped humanity’s past. Why study Oceanographic History?. Understand how and why people apply marine sciences today

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History of Oceanography

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  1. History of Oceanography

  2. Why study historic oceanography? • Connected to the world’s overall history • Commerce, warfare, resources, weather • The oceans have shaped humanity’s past

  3. Why study Oceanographic History? • Understand how and why people apply marine sciences today • Oceanography’s history is about people, not just oceans and test tubes.

  4. Branches of Oceanography • Physical Oceanography - study of the motions of seawater, particularly waves currents and tidal motion. • Chemical Oceanography - chemistry of seawater and reactions between the atmosphere and hydrosphere. More recently looks at how changes in seawater temperature (El Nino) and salinity affect global climate.

  5. Branches of Oceanography • Biological Oceanography - study of life in the oceans, includes marine biology and ecology. • Geological Oceanography - study of the shape and geologic features of the ocean floor.

  6. Ancient Uses and Explorations (5000 B.C. to 800 A.D.) • Not sure when ocean voyages actually began • Fish hooks and spears dated approximately 5000 B.C. • Paleolithic and Neolithic periods • Earliest humans: 1.6 million yr ago (mya) • Food gathering

  7. Early Times: • Earliest recorded sea voyage – Egyptians about 3200 B.C. • Egyptians: • Offshore fishing • Exploration • Boat builders

  8. Phoenician Explorations • Most important early Western seafarers • Motivated by trade, Phoenicians traveled incredible distances • Established first trade routes throughout the Mediterranean and as far north as Great Britain

  9. Phoenician Navigation • Stayed within sight of land • Traveled at night – steered by observing constellations and the North Star (called the Phoenician Star in ancient world) • Had a Navy

  10. Polynesian Exploration • Between 2000 and 500 B.C. • Often traveled thousands of kilometers across open ocean • Open canoes cut from tree trunks • Developed stick maps with ocean currents • Settled most of the islands in the Pacific Ocean hundreds of years before Europeans reached Pacific Ocean through observations of waves, cloud formations, stars

  11. Polynesian Significance • Earliest known regular, long-distance, open-ocean seafaring beyond sight of land • Early celestial navigators (followed stars)

  12. Greek Exploration • First who used mathematical principles and developed sophisticated maps for seafaring (used science & math) • Pytheas – Greek explorer, noted that he could predict tides in Atlantic based on phases of moon • He also measured angle between horizon and the North Star to determine position – improved navigation

  13. Eratosthenes (264-194 B.C) • 2 major contributions that furthered Pytheas’ work: • Calculated Earth’s Circumference ~40,000 km • Invented first latitude/longitude system

  14. Map of World – According to Eratosthenes

  15. Ptolemy (100-168 A.D.) • Created map of Earth that showed a portion of the Earth as a sphere on flat paper. • Produced first world atlas Improved longitude/latitude system • System still used today

  16. Middle Ages (800 A.D.-1400)

  17. Vikings (790 A.D. to 1100) • Vikings of Scandinavia were active explorers during The 9th century • Discovered Iceland and Greenland • Leif Eriksson – son of Eric The Red, set off in search of timber for Greenland Colony and discovered North America (Newfoundland, Canada)

  18. Vikings: • Improvements in shipbuilding • Established trade and colonization through the North Atlantic

  19. The Viking Voyages

  20. Arabs: • Description of currents associated with seasonal monsoons • Trade routes to China from the Persian Gulf • Preserved and improved Greek and Roman knowledge

  21. China: • Development of the compass • Established trade routes to Persian Gulf

  22. China: cont. • 7 epic voyages of Admiral Zheng He • Exploration of the western Pacific and Indian Oceans to east Africa • Short period of intense outreach to other cultures • Voyages ended and China turned inward

  23. Chinese Exploration • The Chinese Ming Dynasty sent large convoys of ships out on missions in which seven voyages were made • There ships were more technologically advanced than anything in Europe, consisting of five masts and magnetic compasses and navigational charts • The Ming Dynasty reached as far as Africa

  24. Silk and Spice Trade Route

  25. European Exploration and the Renaissance

  26. Prince Henry the navigator, (1420’s) • Founded the first school of navigation • Established a naval observatory • Trained other navigators and sailors

  27. Christopher Columbus (1490’s) • Was attempting to find a west-ward route to India when he reached the Bahama Islands • Conducted 4 trans-Atlantic voyages to find a route to the east Indies

  28. Columbus

  29. Ferdinand Magellan (1520) • Led the expedition that was the first successful circumnavigation of the Earth • Established the length of a degree of latitude and measured the circumference of Earth • Was killed in the Philippines (battled with the natives)

  30. Magellan’s Circumnavigation of World

  31. Sir Francis Drake (1570’s) • Followed Magellan and explored the western US coast as far north as the Canada border • Circumnavigated the globe

  32. The Beginning of Ocean Science

  33. 17th Century • The Beginning of Earth Science • Curiosity about Earth flourishes • Johannes Kepler • Described planetary motion • Galileo Galilei • Mass, weight, and acceleration • Isaac Newton • Principia and law of gravity

  34. The Importance of Charts and Navigational Information • Enabled trade, travel, and exploration • Development of more accurate navigational charts and instruments • Relationship between time and longitude • John Harrison; first chronometer to keep accurate time at sea • First hydrographic offices to map the oceans established in France (1720) and Britain (1795)

  35. The Importance of Charts and Navigational Information, continued • Voyages of James Cook • Used Harrison’s chronometer to update and correct navigational charts • Explored and charted the South Pacific, regions of Antarctic waters, east Australia and New Zealand, and sailed through the Bering Strait • European discoverer of Hawaii • Benjamin Franklin • Published a chart of Gulf Stream and helped establish a more rapid sailing route between the Europe and the US east coast • Compare Figures 1.10 and 1.11 • National and commercial interests • U.S. Survey of the Coast set up in 1807 by Thomas Jefferson (now known as the National Ocean Survey)

  36. Cook’s Expedition(1768 – 1779) • Made 1st accurate maps of many regions in the ocean w/ new invention • Chronometer invented by John Harrison • Chronometer is a time piece capable of keeping accurate time aboard ship at sea

  37. The Three Voyages of Captain James Cook

  38. Ben Franklin and the Gulf Stream (1777) • Noted northerly routed ship from Europe took longer than ships that came by a longer more southerly route • Learned about gulf stream from nephew, who gave his uncle a chart • Franklin had the chart printed and distributed to the captains of mail ships. • They shortened their inbound voyages by avoiding the current and they shortened their outbound voyages by using the current.

  39. Chronometer and Ben Franklin’s published Gulf Stream Chart

  40. 18th Century • Previous exploration driven by military, trade, or conquest objectives • Royal Navy of Britain launched voyages with objectives of exploration, mapping and projecting British presence around the world

  41. Ocean Science Begins • Botanists and naturalists go to sea • Collect, describe, and classify organisms • Investigations of microscopic drifting plants and animals (plankton) • Scientific interest based on practical reasons • Navigation, tide prediction, and safety • Importance of government support • Laying of transatlantic telegraph cables

  42. Father of Oceanography… Matthew Maury • Matthew Maury, in charge of the Depot of Naval charts and instruments. • Organized first international meteorological conference to establish uniform methods • Published a summarized version of data in first Oceanographic textbook in 1855

  43. Ocean Science Begins, continued • Charles Darwin serves as naturalist aboard the Beagle • Develops a theory of atoll formation • Charles Wyville Thompson publishes The Depths of the Sea (1873), now regarded as the first oceanography textbook • Thomas Henry Huxley investigates deep sea sediments for signs of primitive life to support Darwin’s theory of evolution

  44. Darwin, Coral Reefs and Biological Evolution • From 1831 to 1836 a naturalist for the HMS Beagle circumnavigated the southern oceans and oceanic islands. • Darwin observed birds and other organisms on isolated islands, most of his research took place in the Galapagos Islands. • In 1859, his observations were published in the book “On the origin of Species”.

  45. Voyage of the Beagle (Charles Darwin)

  46. The Rosses, Edward Forbes, and life in the deep sea • John Ross took samples and animals in Baffin bay (Canada) Later James Ross took samples from Antarctic ocean bottom at 4.3 Miles • John Ross and James Ross found that there are some bottom dwelling creatures in Baffin Bay and Antarctic Ocean. They discovered that deep Atlantic is uniformly cold. • Forbes – Oceans divided into life-depth zones; concluded that ocean life decrease as depth increases. This contrasted with Rosses finings and created dispute for decades in Britain.

  47. The Challenger Expedition • Comprehensive oceanographic expedition • Naval corvette refitted with laboratories, winches, and sounding scope • Circumnavigation • 361 sounding stations • Collected deep-sea water samples • Investigated deep-water motion • Temperature measurements at all depths • Thousands of biological and sea-bottom samples • Analysis and compilation of data continued for 20 years • Began oceanography as a modern science • Prestige stimulated expeditions by other nations

  48. The Ocean as Laboratory : The Challenger Expedition (1872-1876) • The expedition covered 79,178 miles. • Directed by C. Wyville Thompson • 2 contributions: • Discovery and classification of 4,717 new marine species • Measurement of record water depth at the Mariana Trench of 26,847 feet.

  49. The Challenger Expedition, continued

  50. Oceanography as Science • Transformation of oceanography • Descriptive science  quantitative science • Hypothesis testing by gathering data • Theoretical models of ocean circulation • Fridtjof Nansen • Voyage of the Fram to reach the North Pole • Nansen bottle for deep water sampling • International scientific cooperation • Motivated by fluctuations in commercial fish • Advances in theoretical oceanography • Development of new instruments

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