Chapter 1: Knowing the Ocean World
An Ocean World
• Ocean creatures provide 2% of humanity’s food
• 1/3 of the world’s petroleum and natural gas are pumped from beneath the ocean floor • ~ 71% world is covered by water
• Ocean – vast body of saline water that occupies the depressions of the earth’s surface • 97% of the water on or near the earth’s surface is contained in the ocean; less than 3% is held in land ice, groundwater, and freshwater lakes and rivers • [pic]
Marine Science, Oceanography, and the Nature of Science
OCEANOGRAPHY – PROCESS OF DISCOVERING UNIFYING PRINCIPLES IN DATA OBTAINED FROM THE OCEAN, ITS ASSOCIATED LIFE FORMS, AND THE BORDERING LANDS. It draws on several different principles... • Marine geology – the study of the earth’s crust and compositions • Physical oceanography – the study of waves and currents, climate predictions • Marine biology – study of nature and distribution of marine organisms • Chemical oceanography – the study of the gasses and solids dissolved in the ocean • Marine engineering – the design and construction of structures used in or on the ocean
SCIENCE – SYSTEMATIC PROCESS OF ASKING QUESTIONS ABOUT THE OBSERVABLE WORLD BY GATHERING AND STUDYING DATA… • Curiosity – a question arises about an event or situation • Observations
• Hypothesis – a tentative explanation is proposed
• Experiments – test are undertaken in nature/laboratory • Theory – explanation for observers that is accepted by most researchers • Law – principles explaining events in nature that have been observed to occur with unvarying uniformity under the same conditions
Early Voyaging and Discovery
- Voyaging – traveling on the ocean for a specific purpose • Chinese – engineered an extensive system of inland waterways (commerce) o Invented the central rudder, water tight compartments, and sails on multiple masts • Settlement of the pacific islands
• The Polynesian colonies are an example of knowledge of oceans and marine science used to colonize a vast number of islands
SCIENCE OF VOYAGING
Pythagoras – said that the earth was round and taught that the universe followed mathematical laws Maybe Pythagoras was a keen observer at the beach….
1. As you stand at the seashore and contemplate the horizon, the edge out there, you are contemplating the roundness of the earth. If the earth were flat, you could see a long ways. But because it is round (spherical), objects are “hidden” below the horizon. 2. If you can estimate the distance to the horizon, you can use the simple math of the Pythagoras and his right triangles to calculate the circumference of the earth with surprising accuracy. All of that by just looking at the horizon at the seashore; circumference = 24,500 miles.
Latitude – imaginary line on the earth’s surface running parallel to the equator Longitude – imaginary lines on the earth’s surface running north and south and converging at the pole
THE AGE OF DISCOVERY
• Henry the navigator – explorers under his patronage compiled detailed charts and explored the west coast of Africa • Christopher Columbus – although he never saw the mainland of North America, his stories inspired other explorers to follow. o He estimated that the earth was only half of its actual size. The smallest estimate in history. • Ferdinand Magellan – although Magellan died en route, the small surviving portion of his crew, circumnavigated the world
JAMES COOK – 1768 HMS Endeavor
A commander in the British royal navy, is credited with leading voyages that greatly contributed to scientific oceanography… • Verification of calculation of planetary orbits
• Charting of New Zealand and the Great Barrier Reef, Tonga, and the Easter Islands • Initiation of friendly relations with many native populations • Sampling marine life,...