History of Oceanography
A. Ancient people living along the coast must have been very curious about the regions underneath the ocean surface as well as waves, the rise and fall of the tides, and other coastal processes. Such people were actually the first oceanographers. For example, as long as 24 centuries ago, a Mediterranean captain on a voyage to Egypt knew that when the plummet at the end of his 10-fathom (1.83 m = 6 ft) sounding line reached a mud bottom he was over the toe of the Nile's delta and that another day's travel should bring him within sight of a port at the delta's head. The navigator, with only a short sounding line for a tool, had learned something about the bottom of the Mediterranean Sea.
B. Gathering food, fishing, trading, migrating to more promising regions, etc. are other endeavors that yielded lots of information about the sea. These early investigations of the sea were motivated by the requirements of daily survival rather than by the reasons driving oceanographic exploration today:
1. exploiting marine food, energy, and mineral resources
2. understanding climate change
3. minimizing the impact of natural disasters such as tsunami, hurricanes
4. assessing humanity's impact on our environment
5. understanding earth processes such as biogeochemical cycling, plate tectonics, etc.
C. Later in history conquest, enrichment of government treasuries, and enhancement of political power became pressing reasons for venturing out onto the seas.
D. A number of maps go so far back into antiquity that historians suggest that they originated in a prehistoric civilization much more advanced than Greece or Egypt. Their existence and accuracy is often difficult to explain in terms of what historians and anthropologists believe some ancient cultures knew about their world. For example, a Turkish map of 1559 is remarkable in that it draws the entire United States in almost perfect outline, including the west coast and Canada even up to the land bridge from Siberia to Alaska. This land bridge could only have existed during the Ice Age no less than 10,000 ybp.
1. Charts developed by early seafarers were jealously guarded and were destroyed before ships could be captured. Seafaring nations like Spain kept all their maps locked in the royal vaults, copies were distributed only to the most trustworthy captains. Often fake maps were made and allowed to fall into the hands of enemies, so that they would die of thirst and hunger in the middle of trackless oceans. Such secrecy caused many ancient maps to be lost making the job of the historian even more difficult.
2. Usually the state of cartography in any ancient nation was a barometer of that state's attainments. But sometimes a nation, despite its crude scientific status, charted its land and seacoast quite accurately. For instance, the Eskimos, without any surveying aids, have made maps of large areas of northern Canada which compare quite accurately to those made by scientists with modern instruments.
II. Chronology of great marine inventions, advances in cartography, great voyages and discoveries -- We haven't always had many of the devices, maps, and vessels we take for granted and I want to point out the things that contributed the most to our understanding of, and interactions with, the ocean. Advances in technology and our understanding of Earth have often influenced history. Such a chronology also gives you an idea of what different cultures were doing at different times in the past.
A. Early History - until about 150 AD.
1. 7250 B.C.-The earliest recorded sea voyage dates back to about this time, when there is evidence of sea trading between the Greek mainland and the Aegean island of Melos.
a. However early human migrations also argue for extensive seafaring. Around 10000 years ago western Europe was colonized by peoples from Africa who must have crossed the Strait of Gibraltar (6 miles or 10 kilometers).
2. 4000 B.C. – Egyptians develop arts of shipbuilding and ocean piloting.
3. 4000-2000 B.C. The Polynesians constructed elaborate vessels complete with living quarters for people and animals. These were used to transoceanic voyages to colonize islands in the Pacific, including Hawaii. They are believed to have first ventured out from the area of Borneo between 4000 and 2000 B.C. and to have reached Hawaii in about 500 A.D.
a. They navigated by the stars winds, tides, waves and currents.
4. 2500 B.C. - The oldest map known to man is a baked clay tablet engraved over 4500 years bp by an unknown Babylonian, however, people may have been drawing maps of even the poles as early as 10,000 years before this. Apparently the Babylonians were also producing sea charts by this time.
5. 1500-500 B.C. - The premier shipbuilders, sailors, and traders of the ancient world were the intrepid Phoenicians, who for 1000 years from 1500 B.C. to 500 B.C. ruled the Mediterranean after the decline of the Egyptian empire. They didn't conquer the world with swords but with manufactured goods and commerce. A great deal more would have been known of them if the Romans (146 B.C.) had not burned Carthage with its 100,000 volume library. Phoenicia was located on a narrow 100-mile wide strip of land where Syria and Lebanon stand today.
a. Phoenicians made sea maps from about 1200 B.C. and for a millennium were the world's greatest sailors, using charts to navigate their vessels between rocks, around shallows, and through channels and narrow straits. They were masters of celestial navigation too, and taught the Greeks how to use stars to guide ships at night. Any Phoenician captain who learned of a safer route passed the information on via hand-drawn maps to other Phoenicians but never to strangers.
b. Herodotus claims that the Phoenicians had circumnavigated Africa by 600 B.C. fully 2000 years before the Portuguese. In fact, the Phoenician navigator Hanno reported that he circumnavigated Africa in 500 B.C. and observed that the noon sun shone in the north at the southern end of Africa. Ancient learned men laughed at him, but today we accept this as proof that he did make the trip.
c. They are known to have gone as far as England in search of tin.
d. Phoenicia vanished as a separate country in 64 B.C. when the Romans took over and added her to their province of Syria. Their decline actually began even earlier when Alexander the Great rampaged through the area in 333 B.C. and captured a number of her cities. However, they left us an undeniable legacy. It was through the naval genius of the Phoenicians that the Greeks, rather than the Persians, came to power in the ancient world. Without the naval superiority that the Phoenicians passed on to the Greeks, western civilization (born in Greek culture) would not have developed as it did.
6. 600 B.C. - Pytheas of Massilia rounded Spain and circumnavigated Britain. Massilia is now the city of Marseilles on the southern coast of France.
7. 450 B.C. - A Greek map (made by Herodotus?) shows Thalassa, as the Mediterranean was called at the time, encompassed by land, and in turn surrounded by the endlessly circling river “Oceanus”. This was the perception learned Greeks had of the geography of their world.
a. Most of the maps surviving from the fourth century B.C. treat the Earth as a sphere and most intelligent Greeks strongly believed that the Earth was round. On many old Greek maps, the Earth was designated with poles, tropics, climatic zones, and the Equator.
8. 4th cent. B.C. - Alexander the Great reached the shores of the Caspian Sea, sailed down the Indus, and dispatched Admiral Nearchus with a fleet along the coast of southern Asia while he marched overland with his army.
9. Many ocean features and processes were known in European antiquity. Aristotle (384-322 B.C.) knew that evaporation = precipitation around the Earth since the sea didn't dry up. He believed the sea occupied the deepest parts of the Earth's surface and he began to catalog marine organisms.
10. By the 3rd century B.C. navigators were using the Pole Star to determine latitude.
11. 240 B.C. - Eratosthenes (a scientist in charge of the Library of Alexandria around 240 B.C.) determines circumference of Earth. He could do this because he knew that the distance between the city of Syene (south, now called Aswan) and Alexandria (north) was 500 miles on a straight north/south line. He also knew that the sun reached it’s highest point in the sky at the same time of day in both places. However, at Syene there were no shadows at midday, but in Alexandria the sun cast a shadow from a pole at an angle equal to one-fiftieth part of a circle. Therefore the curve, multiplied to the completion of a circle, came out to almost 25,000 miles (24,881mi.). Eratosthenes only missed a completely accurate measurement because the Earth is not a perfect sphere.
12. 2nd century B.C.- Navigational astrolabe (for determining the position of Sun and stars) invented by Greek. Such a device was necessary to permit navigation in the absence of landmarks (i.e., away from shore).
13. The art of navigational map making did not advance much under the Romans because Rome was intent upon land conquests and containing the uncouth Germanic tribes that threatened her borders.
14. 150 A.D. - Ptolemy of Egypt's map of the world endured and served mankind for over 1200 years. Some of his mistakes did not disappear from maps until the late 18th century.
a. It's major flaws were that he accepted a value of 18,000 miles for the circumference of the Earth and, of course, that he was unaware of the existence of the Americas.
b. It designated latitudes and longitudes.
B. The Middle Ages (150 AD to late 1400's)
1. Not much happened in Europe for the first 1000 yrs A.D. to advance Man's knowledge of the sea although shipbuilding improved significantly in the latter part of the Middle Ages.
2. 673-735 A.D. - An English historian, the Venerable Bede, figured out that the moon controlled the tides.
3. 700-1000 A.D.-The Vikings discover Greenland and America, although their voyages are largely unrecorded and they left no permanent settlements.
4. 9th cent. A.D.- Arabs invent compass.
a. Obviously, the compass is a much more recent invention in navigation than maps.
b. In a Chinese manuscript of the late 11th century the compass is discussed, but we have no evidence of any application of this knowledge by the Chinese at the time.
c. The earliest mention of the compass being used in Europe occurs in a Latin treatise written about 1187.
d. In the 1500's compasses were still very crude and of highly variable accuracy.
e. It wasn't until the mid 1800's that sailors recognized that iron objects placed too close to the compass could cause severe errors.
5. 12th cent. A.D.-Normans invent ship's rudder.
6. By the 1300’s Europeans had established successful trade routes including some partial ocean crossings, especially around the Mediterranean.
7. 1400's - Three-masted ship-rigged vessels are developed
8. 1405-1433 A.D.-The Chinese (Ming dynasty) took seven peacetime voyages to show the magnificence of the Chinese empire. The ships were far larger than anything in Europe at the time. The largest had 9 masts, was 444 feet long and 180 feet wide. They had transverse bulkheads, and used magnetic compasses and elaborate, detailed navigation charts. They did not seek to conquer, collect treasure, or gather scientific information. Because these voyages were so costly and did not contribute anything to Chinese culture they were abandoned in the early 1400's and made no lasting contribution to improving our understanding of the ocean.
C. The Age of Discovery (Latest 1400's to early 1700's)
1. The great age of ocean exploration began in the 15th century probably stimulated by the new knowledge gained from the rediscovery of Ptolemy's (150 A.D.) maps as well as by:
a. Portugal's early efforts to explore the Atlantic.
1) Explored the Canary Islands off NW Africa in 1416.
2) In 1418 Prince Henry the Navigator founded a school for the study of navigation and sent ships out to explore the world.
3) Azores (~24oW & 37oN in Atlantic) were discovered between 1427 and 1432.
4) The African slave trade began in 1441.
b. The development of 3-masted ships.
c. The need to replace the overland trade routes to China and India. The decline of the Mongol Empire in central Asia and the fall of Constantinople to the Turks in 1453 had cut off these ancient trade routes. And the eastern end of the Mediterranean was dominated by hostile Islamic peoples. Also for centuries sea transport was far easier and cheaper than the overland routes.
2. The Portuguese explorer, Diaz, rounded the tip of Africa (Cape of Good Hope) in 1488.
3. ~1492 - Martin Behaim, a German who worked for Portugal during the great age of discoveries, made a globe (the oldest in existence) based on the flawed maps of Ptolemy. This globe pictured the west coast of Europe and the east coast of Asia facing each other across the Atlantic. His globe showed a width of only 126o of longitude separating Spain from Asia. (The distance is actually about 230o of longitude, but of course the Americas are “in the way”.) This error shortened distances considerably and convinced Columbus that the trip to Asia across the vast, uncharted, western ocean could be accomplished.
a. Eratosthenes (240 B.C.) had been right about the circumference, but along came someone named Posidonius (135-50 B.C.). He revised the estimate downwards by 25%. Ptolemy, 200 years later, chose the Posidonius estimate, thus perpetuating the error all the way into the fifteenth century.
4. 1492-Columbus sails to the Bahamas
5. 1497-Genoa-born and Henry VII-backed John Cabot sails to Labrador, Nova Scotia, and Newfoundland giving England a claim to North America.
6. 1498- Vasco da Gama reached India in May 1498. His discovery opened up a profitable trade route from Portugal to India.
7. Maps began to improve after 1500 when compasses and better ships did much to encourage exploration. Also, when sea adventurers penetrated the "unknown" seas of Africa and the Americas in the 15th and 16th centuries, new information became available to cartographers. Upon visiting Java, the Portuguese obtained a Javanese map showing lands all the way to China and as far away as Brazil.
8. 1519-1521-Ferdinand Magellan's expedition circumnavigates the globe.
9. Other important explorers included Balboa, Ponce de Leon, and Vespucci
10. Mercator (1512-1594) developed his projection, which is the basis of map-making today. The Mercator projection (a rectangular grid system showing distances north and south of the equator and east and west of the prime meridian was available after 1599 and permitted projection of the spherical Earth onto a flat piece of paper.)
11. 1529 - Portuguese cartographer made a map of the entire world. This was the first map to show the huge expanse of the Pacific with India and China properly located, and it included both the North and South Poles! In 1532 another world map showed Antarctica almost exactly as it exists today, complete with mountain ranges. AND YET History tells us that it wasn't until the 19th century that sailors began to explore the polar regions???
12. 1542-Portuguese ships visit Japan for the first time.
13. 1577-1580-Sir Francis Drake, with the encouragement of Queen Elizabeth I, sails around the world capturing Spanish ships and cargoes enhancing development of British maritime traditions.
14. 1576-1610 – Forbisher and Hudson search for a Northwest Passage to the Orient.
15. 1602 - The British East India Company is chartered.
16. 1608 - Telescope invented by Lippershey of Netherlands.
17. 1607-1611 Henry Hudson among many others explored North America as the major western European nations established colonies and divided up the New World.
18. 1620 - The Pilgrims land at Plymouth Rock.
19. 1643 - Torricelli of Italy invents barometer.
a. Told mariners when big storms were coming
b. They couldn't just turn on the weather radio could they?
20. 17th century - The English took over leadership in the field of mapmaking.
21. 1731-Hadley of England perfects the sextant that measures the distance between two objects and permits determination of latitude. His invention was called "Hadley's octant" because of the arc it measured-i.e. one eighth (45o) of a complete circle. The name fell out of use, but Hadley's Octant lives on as the designation the French astronomer La Caille gave in 1752 to a group of stars in the Southern Hemisphere.
a. Allowed mariners to locate themselves in a north/south direction with respect to the equator and the poles.
22. 1735 – John Harrison of England invents chronometer. This was the first clock that could keep time to within a few seconds over the course of a year-long sea voyage.
a. The Yorkshire inventor won the British Admiralty contest offering 20,000 pounds to anyone who could devise a method of determining longitude within a half degree. This meant that the device could not gain or lose more than 3 seconds/day.
1) ($40,000 then and several million dollars today) - if you try to imagine how much money this represented ~270 years ago I think you can appreciate what an important breakthrough this was.
2) He finally claimed his prize in 1773 after 40 tumultuous years of political intrigue, international warfare, academic backbiting, scientific revolution, and economic upheaval. He was a watchmaker with no formal education or apprenticeship.
b. The offer was authorized by Queen Anne in 1714 as a result of the great tragedy near the Scilly Islands (off the SW tip of England) in 1707 when 4 homebound British warships miscalculated longitude and ran aground with the loss of 2000 men.
1) The vast majority of sailors couldn't swim
c. Because the Earth rotates it is necessary to know what time of day it is in order to determine longitude.
D. Beginning of Voyaging for Science (Late 1700's to 20th century)
1. 1769 - Benjamin Franklin publishes one of the earliest maps of the Gulf Stream - the strong current system along the U.S. Atlantic coast.
2. 1775 - Perier of France invents steamship.
3. 1768-1779 - Captain James Cook makes his three great voyages of exploration to chart the Pacific--the first truly scientific expeditions of the century
4. 1776-Bushnell of America invents first workable submarine.
5. 1807- Development of commercial steamship.
6. Early 1800's - US Congress established and funded various institutions to study the oceans.
7. 1831-1836-The voyage of the Beagle under Captain Fitzroy along the coasts of Patagonia, Chile and Peru, during which Charles Darwin, the ship's naturalist, makes observations providing the basis for his Theory of Evolution.
8. It was about this time that Edward Forbes (1815-1854) developed his AZOIC theory. He had collected animals in the Aegean Sea and noticed that fewer and fewer species were caught as his nets went deeper. He concluded that most deep- ocean waters were devoid of animal life. This theory was not refuted until the 1860's when a trans-oceanic cable from 2000 meters (6600 feet) in the Mediterranean Sea raised for repairs had on it living animals.
9. 1838-42-An American scientific expedition led by Captain Charles Wilkes, with J.D. Dana as naturalist, makes important studies of tides and currents of the Antarctic and the western North American coast.
10. Matthew Maury, a naval officer, was appointed Superintendent of a Depot of charts and Instruments in 1842. His activities and information gathering revolutionized navigation and cut weeks off transoceanic runs by U.S. clipper ships, the fastest ships of their time. His sounding and bottom-sampling projects were used to make maps of the Atlantic Ocean floor. In 1853 he organized the first international meteorological conference, which led to international cooperation in collecting weather information at sea. His popular and influential book, The Physical Geography of the Sea (1855), was the first major oceanographic work in English. He is called the father of physical oceanography.
11. In 1871 the U. S. established the U.S. Fish Commission to assist in the regulation and protection of fish stocks. The first U.S. research vessel, (1882) built especially for ocean studies was the Albatross and belonged to the U.S. Fish Commission.
12. 1872-1876 - A scientific party under Sir Wyville Thomson and financed by the Royal society of London embarked in a ship provided by the British Admiralty to investigate "everything about the sea" aboard the CHALLENGER. They planned to study physical and biological conditions in every ocean, recording whatever might influence the distribution of marine organisms They took water samples and temperature measurements, recorded currents and barometric pressures and collected bottom samples. Fishes were caught in nets dragged behind the ship. Traveled 109,000 km (68,000 miles) and sampled all ocean basins except the Arctic. Brought back data that eventually filled 50 large volumes and represented a major turning point in the development of ocean science.
a. Some of the methods devised on this cruise are still used today.
13. 1888 - Baird established a research center in Woods Hole on Cape Cod, which stimulated the later development of the Marine Biological Laboratory (1888) and the Woods Hole Oceanographic Institution (1930), probably the world's premier oceanographic research center.
14. 1893-1896 - A Norwegian scientist Fridtjof Nansen collected valuable oceanographic, magnetic, and meteorological information in the Arctic. The rest of his career was equally as distinguished including the invention of a water-sampling bottle that permits isolation of water samples from various depths. This lays the groundwork for future Arctic research. He also tested hypotheses about Arctic currents.
15. 1895-Marconi of Italy invents wireless telegraph.
16. " - Diesel of Germany invents diesel engine.
E. The Age of Modern Oceanographic Exploration (1900's to early 21st century)
1. In the early 1900's a number of federal government agencies were established and funded to advance oceanography.
2. 1909 Admiral Robert Peary reaches the North Pole.
3. 1909-Evinrude of U.S. invents outboard engine.
4. 1912-Captain Roald Amundsen reaches the South Pole.
5. 1912 – Wegener proposes Continental Drift
6. 1917-Mason of U.S. invents the ECHO-SOUNDER , which was used as a submarine detector.
7. Virtually all civilian ocean research ceased in 1939 with the outbreak of World War II, when scientific resources were mobilized. However, many advances were made in instrumentation, and our understanding of the ocean was greatly improved. These results were made available after the war to the scientific community.
a. For example, there were major advances in predicting wave conditions (important for amphibious invasions). Mapping features of ocean basins, such as the magnetic field, was greatly expanded to improve the ability to detect submarines.
8. Beginning in the early 1950's, as a result of university contributions to the war effort, government support for academic ocean research and education was greatly increased. This permitted universities to play a major role in ocean studies for the first time. Ships and scientists from many countries cooperated to collect oceanographic data starting with the International Geophysical Year (IGY) of 1957-58.
a. The next major event was the International Decade of Ocean Exploration (IDOE), led by US. The 10 years of studies involved countries around the world in learning more about the ocean before it became a major source of food, fuel, and minerals as traditional land-based supplies of these commodities were used up.(One IDOE project showed the distribution and characteristics of deep-sea manganese nodules (Cu,Ni,Co).
9. 1955-U.S. scientists develop 1st nuclear submarine.
10. 1959- " " " " " surface ship.
11. 1960’s - Deep ocean floor exploration and the beginnings of Plate Tectonic Theory. Adaptation of the World War II echo sounder to measure ocean depths was a major breakthrough. It permitted the rapid, accurate determination of ocean depths.
a. Systematic mapping of deep-ocean basins began in the late 1940's. Scientists at Columbia University's Lamont Doherty Geological Observatory carried out pioneering surveys, guided by Maurice Ewing. These surveys dramatically improved the maps of the sea floor. (E.G. the Midocean Ridges were shown to be part of world's longest mountain range.)
b. Using data from these surveys, Harry H. Hess of Princeton University theorized in 1962 that movements deep in the Earth slowly moved the crust causing continents to break apart, land masses to move, and new ocean basins to form. Hess hypothesized that new oceanic crust was formed by volcanic eruptions at Midocean Ridges and moved toward the trenches, where it was destroyed. i.e., Seafloor spreading.
12. 1960's ? Loran navigational system based on radio signals developed. Using two or more sets of land stations, an estimate of position accurate to within 165-1300 feet is possible.
13. In 1967 the use of drill ships began. These supplied samples of rocks and sediments on the ocean bottom providing the final evidence to prove the Theory of Plate Tectonics.
14. 1970's and 1980's - evolution of satellite navigation (GPS). Good to within a few hundred feet.
15. 1977 - Robert Ballard from WHOI discovers the thriving benthic habitats at Mid-ocean Ridge hydrothermal vents.
III. Instrumentation of modern oceanographic research
A. Meters used to measure current velocities and directions.
B. Floats used to track water movements.
1. Swallow float developed from IGY activities. It is a metal cylinder precisely weighted to float at a predetermined depth in the ocean. It carries a "pinger", a device that emits sound pulses so that its movements can be tracked by listening stations on ships or islands
2. Placed in a selected water mass and sends back loci and temperature information on that mass.
C. Nansen and now Niskin bottles for water sampling.
D. Thermometers and now electronic devices called thermistors
E. Earth-orbiting satellites to map slopes of the ocean surface, movement of surface currents, sea surface temperatures or other rapidly changing ocean features that could not be adequately studied from ships travelling slowly over the surface of the sea.
1. Before 1980, when such satellites became more commonly available, oceanographers were "data poor". Now they receive such quantities of data that the largest and fastest computers are needed to store and manipulate the satellite data streams.
F. Unmanned and manned submersibles to sample, study and photograph the depths of the ocean.
G. Drill ships and specialized research ships.
1. Glomar Challenger (1967-1984) and Joides Resolution
2. Ships equipped with special engines to maintain their position precisely without anchoring.