1. Chapter 1 Introduction to Planet “Earth”
Essentials of Oceanography
7th Edition

2. Geography of the oceans
Earth’s oceans:
Cover 70.8% of Earth’s surface
Are interconnected (“world ocean”)
Have huge size and volume (as a reservoir, contain 97% of Earth’s water)

3. The four principal oceans
Pacific
Atlantic
Indian
Arctic
Plus:
Southern or Antarctic Ocean
Figure 1-2

4. Comparing oceans to the continents
Figure 1-3

5. Comparing depth of the oceans to elevation on land
Figure 1-4

6. Early exploration of the oceans
Pacific navigators peopled many remote islands
Figure 1-6

7. Early exploration of the oceans
Advancements of European navigators
Phoenicians explored the Mediterranean Sea and beyond
Pytheas developed method to determine latitude
Eratosthenes calculated circumference of Earth
Ptolemy produced map that shows known land surrounded by largely unexplored oceans

8. Early exploration of the oceans
The Vikings explored the North Atlantic and established many colonies
Figure 1-7

9. Early exploration of the oceans
During the Age of Discovery, Columbus and Magellan make journeys of exploration
Figure 1-8

10. Early exploration of the oceans
Voyaging for science began with English navigator and explorer Captain James Cook
Mapped many unknown islands
Determined outline of the Pacific Ocean
Sampled ocean properties
Modified shipboard diet to eliminate scurvy
Used John Harrison’s chronometer to determine longitude

11. The scientific method
Figure 1-10

12. Origin of the Solar System and Earth
Cloud of gas and space dust (nebula) began to contract about 4.6 billion years ago
The Nebular Hypothesis
Figure 1-12

13. Origin of the Solar System and Earth
Protoplanets were created from the nebula
Protoearth was initially homogenous:
Larger in size than today’s Earth
Had lots of volcanic activity
No continents or oceans
No life

14. Density stratification
Protoearth experiences density stratification
Density = how heavy something is for its size
Density stratification causes high density material to sink while low density material rises
High density material = rock material and metals
Low density material = gases

15. Density stratification creates a layered Earth
Figure 1-13

16. Origin of the oceans
As a result of density stratification, water for the oceans is outgassed from inside Earth
Figure 1-14

17. Origin of the atmosphere
Density stratification caused Earth’s early atmosphere (water vapor and carbon dioxide) to be outgassed from inside Earth
The initial atmosphere was rich in hydrogen and helium
Earth’s present atmosphere is rich in nitrogen and oxygen

18. Photosynthesis releases oxygen to the atmosphere
Figure 1-16

19. Origin of life on Earth
Stanley Miller’s experiment simulating conditions of an early Earth showed that life probably began in the oceans
Figure 1-15

20. Major events in Earth’s development
Figure 1F

21. Essentials of Oceanography 7th Edition
End of Chapter 1
Essentials of Oceanography
7th Edition