Introduction to Oceanography

1. Introduction to Oceanography Dr. Marianne E. McNamara

2. First, An icebreaker… • Your major • Your year/Part time or full time • Your plans • Your objectives • Your interests

3. What is oceanography? • Oceanography is the study of the ocean • An interdisciplinary science: • Geology • Geography • Chemistry • Physics • Biology • Astronomy

4. What is oceanography? • Oceanography consists of several specialized disciplines • Marine Biology (Biological oceanography) • Chemical Oceanography • Geological Oceanography • Physical Oceanography • Marine Engineering • Marine Ecology • Marine Management

5. Oceanography ≠ Dolphins! Chemical Oceanography Biological Oceanography Physical Oceanography Geological Oceanography

6. …but it is one way to unleash your inner dolphin hugger…

7. Got Ocean? • The ocean covers 71% of the Earth’s surface • Accounts for >97% of the Earth’s water! • The average depth of the ocean is 3,800 meters (12,500 feet) and at its deepest depth is 7,000 ft greater than the highest elevation on land (Mt. Everest 29,000 ft; Mariana Trench 36,163 ft) • The average temperature of the ocean is only 3.9 ̊C (39 ̊F)

10. Oceanography • For our convenience, the oceans are separated into 5 named ocean basins (and many smaller seas), but they all constitute one world ocean; one great intermixing mass of saline (salty) water • All oceans are, in fact, interconnected with one another

11. One World Ocean • Pacific Ocean (the largest) • Atlantic Ocean • Indian Ocean • Arctic Ocean • Southern Ocean

12. One World Ocean Arctic Ocean Atlantic Ocean Pacific Ocean Indian Ocean Southern Ocean http://www.gebco.net/data_and_products/gebco_world_map/images/gda_world_map_large.jpg

13. The Ocean’s Origins • The Earth is believed to be 4.6 billion years old • During the Earth’s formation, heavy (dense) metals such as iron and nickel gravitated towards the hot center in a molten state • At the same time, lighter elements such as aluminum and silicon rose towards the surface, forming the Earth’s crust

14. The Ocean’s Origins • Crust is made up of different rock types, and so is thinner and thicker in places • Thick = land; thin = ocean!

15. The Ocean’s Origins • Eventually, the young Earth cooled enough such that water vapor condensed and collected in the ocean basins • As water collected, it dissolved minerals within the rocks • After 20 million years of rain, the oceans were born!

16. Why study oceanography? • ~80% of all Americans live within 1 hour of an ocean or Great Lake • 100% of all Long Islanders live within 1 hour of the Atlantic Ocean • 50% of the world’s population live on a coastline

17. Why study oceanography? We live on Long ISLAND; The ocean is our backyard!!!

18. Why study oceanography? • Our Earth is a BLUE planet • Why blue?

19. Why study oceanography? • More than half of the oxygen we breath is produced in the ocean! http://www.nasa.gov/centers/goddard/images/content/95573main_plankton_satellite.jpg

20. Why study oceanography? • Oceans moderate the Earth’s climate

21. Why study oceanography? "Old Inlet" breach in Fire Island caused by Sandy. Photo by National Park Service

22. Why study oceanography? • Because it’s the stuff of legends (and nightmares…)

23. Why study oceanography? • Because it’s the stuff of legends (and inspirations)

24. Why study oceanography? • So you can understand this on a deeper level http://www.youtube.com/watch?v=hwlZUKv57B4

25. Why study oceanography?

26. Why study oceanography?

27. Why study oceanography? WHY NOT???!!!

28. Oceanography • Oceanography deals with understanding the complex relationships between physics, geology, chemistry and biology • Oceanography must consider the relationships between land and sea, and within the ocean itself

29. The History of Oceanography • Explorers and scientists have been studying the oceans for millennia and centuries, respectively 1769 chart of the Gulf Stream by Benjamin Franklin

30. History of Oceanography • In fact, the units of latitude and longitude were developed by Alexandrian (Greek) scholars ~200 years BCE • Latitude and longitude are systems of imaginary lines dividing the surface of the Earth • Essential for navigation

31. Latitude and Longitude • Latitude lines run parallel to the equator • Longitude lines run from pole to pole

32. The History of Oceanography • The most famous and extensive study of the ocean was conducted by the British in the 19th century • The HMS Challenger sailed the seas between 1872-1876 • Motivated by economic and military interests • Explored nearly every all parts of the world’s ocean • Seawater samples, biological samples, depths, sediment composition

33. The Challenger expedition • Voyage track from 1872-1876; remains the longest continuous oceanographic survey

34. History of Oceanography • The Challenger expedition successfully disproved the Azoic hypothesis – the belief that no life existed below 550 meters • Collection of life in the depths launched the science of marine biology!

35. Oceanography: The Final Frontier?