Unit 1: Ocean Exploration Chapter 1: Introduction to Marine Science Chapter 2: History of Ocean Exploration

Unit 1: Introduction to Marine Science Chapter 1: Introduction to Marine Science Chapter 2: History of Ocean Exploration

Marine Scientists at Work 4 main branches Biological Oceanography – studies life in ocean Chemical Oceanography – studies chemistry of seawater Geological Oceanography – studies geology of ocean Physical Oceanography – studies the physics of the marine environment

Thinking Like a Scientist Begin with an observation (process of gathering information) Information gathered from observations is data 2 Types of Data Qualitative data: descriptions Quantitative data: expressed as numbers

Thinking Like a Scientist Use data to make inferences (logical interpretation based on prior knowledge) After initial observations, make a hypothesis Hypothesis: proposed scientific explanation for a set of observations

How Scientists Work Designing an experiment: Asking a question Forming a hypothesis Setting up a controlled experiment Independent variable – variable that is changed Dependent variable – depends on the independent variable Record / analyze results Draw a conclusion

Variables and the scientific method

Using the scientific method: Inductive and deductive reasoning

Repeating Investigations Key assumption in science is that experimental results can be reproduced because nature behaves in a consistent manner In other words, you should be able to do someone else’s experiment and get the same results Sometimes you can not test a hypothesis To study animal behavior, one must do a field survey Ethical considerations Surveys

How A Theory Develops As evidence from numerous investigations builds up, a hypothesis may become so well supported it becomes a theory Theory applies to a well tested explanation that unifies a broad range of observations Sometimes you may need more than 1 theory to explain something Ex. Marsupials STOP

Unit 1: Introduction to Marine Science Chapter 1: Introduction to Marine Science Chapter 2: History of Ocean Exploration

History of Ocean Exploration Why study it? History of oceanography is connected to Earth’s history Past helps us understand why / how we apply marine science today It is interesting

History of Ocean Exploration Can be divided into 4 stages: Ancient uses (5000BC – 800AD) Middle Ages (800AD – 1400AD) European Voyages (1400AD – 1700AD) Birth / Growth of Modern Marine Science (1700AD – present)

Prehistory & Rise of Seafaring 3 primary reasons for early civilizations to interact with ocean: Obtain food Discover new lands Means of trade Earliest recorded voyage was 3200BC under Egyptian Pharaoh Snefru

Prehistory & Rise of Seafaring Phoenicians – established 1st trade routes through Mediterranean Polynesian – earliest known regular, long distance, open ocean sailing Greeks – piloting (using constellations / North Star) Pytheas (314BC) – predict tides, determine how far N/S Eratosthenes (264BC – 194BC) – latitude / longitude, Earth’s circumference

Latitude & Longitude Used to identify specific location on Earth Called meridians Run North-South Prime Meridian is the longitude of the Royal naval Observatory in Greenwich, England Latitude Called parallels Run East-West 0 degrees = Equator

Middle Ages Dark Ages Little exploration, mainly trade Advancements in science and geography were suppressed Viking Explorations Established trade routes (Britain, Ireland, S. Europe, N. Africa, Central Asia) 9th Century global warming freed the north of ice allowing exploration of Iceland, Greenland, and N. America

Middle Ages Chinese Magnetic compass Shipbuilding – central rudders, watertight compartments

End of Middle Ages / Route to Africa Renaissance – new interest in science, economics, politics, religion Explorers: Prince Henry the Navigator of Portugal (1440s) – down west coast of Africa Bartholomeu Diaz (1487AD) – around Cape of Good Hope but not to India Vasco de Gama (1497AD) – 1st expedition around Cape to India

Exploration of the New World Christopher Columbus (1492AD) 4 voyages to find Asia / landed in the Caribbean

Exploration of the New World Amerigo Vespucci (1454 – 1512AD) S. America, Amazon, 1st European to recognize it was a new continent

Exploration of the New World Vasco Nunez de Balboa (1500s) – crossed isthmus of Panama & discovered the Pacific

Exploration of the New World Ferdinand Magellan (1519AD) – circumnavigate the globe (260 men / 5 ships – ended w/ 18 men / 1 ship), died in the Philippines

Exploration of the New World Francis Drake (1577AD) – 2nd circumnavigation, treasure, spices

James Cook’s Expeditions October 27, 1728 - February 14, 1779 1st sea exploration devoted to methodical, scientific oceanography Discovered Australia, New Zealand, S. pacific Islands, Hawaii, W. Coast of US and Canada, Bering Straight, Antarctic Circle Used chronometer to determine longitude

US Exploring Expedition 1st significant scientific expedition launched by US led by Lt Charles Wilkes Explored S. Pacific and S. Atlantic Proved the existence of Antarctica

Father of Physical Oceanography Matthew Maury Published The Physical Geography of the Sea which is now considered the 1st textbook on modern oceanography (1855AD) detailed works on sea navigation

Charles Darwin The HMS Beagle began its 5 year voyage in 1831 1859 published The Origin of Species Theories on natural science and evolution of species

Voyage of the Beagle On a five-year voyage on the Beagle, Charles Darwin visited several continents and many remote islands. Darwin’s observations led to a revolutionary theory about the way life changes over time.

The Challenger Expedition 1872 – 1876AD 1st expedition devoted to marine science Took 1st soundings deeper than 4,000m (13,123 ft) – 8,200m (26,900 ft) Collected biological samples Discovered marine organisms in the deep Sampled plankton Catalogued and identified 715 new genera & 4,717 new species

The Challenger Expedition

Oceanography Explosion 3 Expeditions of Industrial Revolution German Meteor Expedition (1925) Water circulation, nutrient dispersal, plankton growth Mapping Atlantic seafloor with echo-sounding tech United States Atlantis Expedition (1931) 1st ship designed for ocean studies Added to Meteor work and mapped the mid-Atlantic ridge HMS Challenger II Expedition (1951) Measure depths of Atlantic, Pacific, and Indian Oceans Used echo-sounding Found deepest part of the ocean – 10,838m (35,558ft) known as Challenger Deep

Submersibles / Self Contained Diving Bathysphere – operated only vertically Bathyscaphe – much like a blimp by releasing ballyst, limited horizontal movement (Trieste) Deep-diving submersible – state of the art, some have robotic arms, easier to use in rough seas (Pisces V)

Submersibles / Self Contained Diving Augustus Siebe (1840) – hard hat diving, air supplied from surface Henry Fleuss (1878) – first workable scuba Jacques Cousteau (1943) – first practical scuba

ROVs, AUVs, Electronic Navigation, Satellites Remotely Operated Vehicle (ROVs) Small unmanned submarine, umbilical to surface Autonomous Underwater Vehicles (AUVs) Piloted by onboard computer, sample the ocean on preprogrammed path LORAN (Long Range Navigation) – later replaced by GPS Radio transmitters Satellites Global observations Understand influence and effect of oceans on global climate system