Oceanography

Oceanography Oceanography – the application of all science to understanding the phenomena of the ocean Oceanography involves chemistry, physics, geology, biology in addition to the study of resources and maritime law and policy

Oceanographic fields or careers Chemical Oceanography – the study of seawater, its composition, and the chemical reactions it undergoes Biological Oceanography - the study of living organisms and how they interact with the ocean. This is very similar to marine biology Physical Oceanography – study of the physical aspects of the ocean, including motion, temperature, density and salinity

Marine Geology – study of the rock and sediment layers on the ocean floor and how the continents drift and oceans form Ocean Engineering – concerned with how to utilize the ocean for man’s benefit (collecting resources, generation of energy, etc.), or how to overcome the challenges the ocean creates Marine Policy – the application of law or political science to the oceans

Characteristics of the Ocean Are economically and recreationally important Almost all international trade moves by shipping on the oceans Climate and weather are strongly influenced by the ocean Is the principal source of the water that goes into the water cycle (rain, surface water, evaporation, etc.) Important source of food

Importance (cont.) Source of many resources – phosphates, tin, manganese, sand, oil deposits and even the water itself May someday be a major source of energy Control of oceans is a major aspect of warfare

In the US, 50% of the population lives within 50 miles of an ocean The oceans and other sources of water cover 72% of the Earth’s surface Less than 35% of the total land is found below the equator – therefore the Southern Hemisphere is over 65% of the Earths’ oceans

The oceans have a volume of 318 million cubic miles Have an average depth of 2.3 miles The oceans’ deepest depth is deeper than the Earth’s highest height Mt. Everest – 8,848 meters (29,029 feet) Challenger Deep in the Mariana Trench – 11, 035 meters (36,204 feet)

Historical Oceanography

Voyaging – traveling on the oceans for a specific purpose seeking Earliest “oceanography” was not out of curiosity, but out of practical purposes Voyaging – traveling on the oceans for a specific purpose seeking New lands to claim and / or conquer Trade routes

The Phoenicians First regular ocean traders – around 1200 B.C. Sailed the Mediterranean, north to the British Islands, and south to the west coast of Africa This was quite an accomplishment due to the simple, primitive ships they used

The Greeks Began to explore the open seas around 900 – 700 B.C Noticed a current flowing out of the Mediterranean Sea – through the Straits of Gibraltar

Mediterranean Sea Straits of Gibraltar Greece

Straits of Gibraltar Satellite imagery where you can actually see the current flowing into the Mediterranean Sea

They believed that only rivers had currents, so the ocean must be one immense river okeanos – Greek word for river oceanus – Latin variant – origin of the word “Ocean”

Neither the Greeks nor the Phoenicians ever ventured far from land

Cartographer – chart maker Slowly over time, sailors began to keep detailed charts showing landmarks, harbors, currents, times between points Cartographer – chart maker Earliest were probably Mediterranean traders First chart drawn around 800 B.C. Chart is to water, as map is to land

Portuguese Nautical Chart, c.1504

Modern Nautical Chart

Library of Alexandria Founded in 3rd Century A.D. In Alexandria, Egypt By Alexander the Great Considered by many to be the worlds first University Site where students and scholars from all over the region studied and researched

Much of the knowledge gained was kept there – both scientific knowledge and extensive charts

Calculated the circumference of the Earth Eratosthenes – Greek astronomer, philosopher, poet and 2nd Librarian of Alexandria Calculated the circumference of the Earth This led to celestial navigation (using stars) Gave rise to the idea of latitude and longitude Was improved upon by Ptolemy (East / West / North / South, degrees and minutes)

400 A.D. – the library was burned under Roman rule Virtually all the charts and records were lost This began a period known as the Dark Ages, which lasted nearly 1000 years

The Vikings Flourished during the Dark Ages Established colonies in Iceland and Greenland Evidence suggests they may have had settlements in North America (1000 A.D.) Were masterful navigators, sailors and ship builders

Polynesians Sailed the South Pacific Considered to be master sailors

One theory is that the South Pacific Islands (Polynesia) were actually colonized by Native South Americans This theory was tested in 1947 by Norwegian explorer and writer Thor Heyerdahl. Sailed from South America to Polynesia in a hand built reed craft – the Kon Tiki

Chinese Made and used practical compass Widely used by 1000 AD This allowed for navigation without using the stars

Improved sail design Used ships with multiple masts Used moveable sails and rudders Developed the watertight bulkhead

Prince Henry the Navigator Portuguese – 1394-1460 Was a patron of sailing – was not himself a sailor Sponsored voyages and financed shipbuilding Led to exploration of Coast of Africa

Christopher Columbus 1492 expedition “Discovered” new world Navigated using “dead reckoning”, his attempts at celestial navigation were flawed and inaccurate Dead reckoning - determining position by measuring time and speed (to calculate distance traveled) and direction (using a compass)

Dead Reckoning

Ferdinand Magellan Was first to circumnavigate the globe – 1519 – 1522 First to sail the Pacific from the Atlantic (via the Strait of Magellan) Gave the Pacific ocean it name - Mar Pacifico (Pacific Ocean) because of its apparent stillness Magellan didn’t complete the journey – was killed in the Philippines

Captain James Cook Explored the pacific, Australia, New Zealand, discovered Hawaii, circumnavigated Antarctica (1768-1779)

Benjamin Franklin Another non-sailor who made a tremendous contribution While postmaster in the US, heard tales of mail reaching US took longer than mail being delivered to Europe Took readings of water temperature on various trans-Atlantic crossings Identified, mapped (and even named) the Gulf Stream

James Clark Ross British Explorer Explored Arctic as part of expedition to reach North Pole (with his uncle Sir John Ross and Admiral Perry) Led Expeditions exploring South Pole (1839 & 1843) Ross ice shelf, Ross seal and RRS James Clark Ross (British Arctic Survey Ship) named for him

HMS Challenger Considered to be the first true oceanographic expedition – set sail for purely research purposes Set out from England in 1872, circled the globe for 4 years Had a crew of 243, and a science party of 6 (Physicists, chemists, and biologists) Collaborated with expert navigators to map the sea

Observation were made at 362 “stations” water depth temperature at various depths weather conditions water conditions at surface and sometimes at depth seafloor samples water samples samples of plant and animal life at various depths

Establishment of Research Facilities and Organizations 1888 – Marine Biological Laboratory - Wood’s Hole, MA 1906 – Musee’ Oceanographique – Monaco 1912 – Scripps Institution of Oceanography – La Jolla, CA 1930 – Wood’s Hole Oceanographic Institution (WHOI) 1970 – National Oceanic and Atmospheric Administration (NOAA) founded by US Gov.