Ocean IntroductionOcean Introduction

Science of voyagesScience of voyages

Applied marine Science began in Applied marine Science began in Alexandria—third century B.C.Alexandria—third century B.C.

Eratosthenes—second librarian was Eratosthenes—second librarian was first to calculate the circumference of first to calculate the circumference of the world. the world.

Invented celestial navigationInvented celestial navigation Cartography flourishedCartography flourished

The dark ages was a time of no real The dark ages was a time of no real scientific development scientific development

The Chinese and Arabs made the first The Chinese and Arabs made the first compass for navigationcompass for navigation

The Polynesians were famous for The Polynesians were famous for their seagoing voyages but resource their seagoing voyages but resource depletion became their downfall.depletion became their downfall.

They were some of the most skilled They were some of the most skilled navigators fig 1.1navigators fig 1.1

VikingsVikings

The Dark Ages were spotted with The Dark Ages were spotted with raids by Vikings in Europe. raids by Vikings in Europe.

Europeans finally banded together to Europeans finally banded together to stop them and this may have stop them and this may have brought about the renaissancebrought about the renaissance

ChineseChinese

Admiral Zheng had the largest fleet Admiral Zheng had the largest fleet of ships ever assembled in 1405of ships ever assembled in 1405

Explored the Indian Ocean, Explored the Indian Ocean, Indonesia, and tip of Africa and Indonesia, and tip of Africa and AntarcticaAntarctica

The primary purpose was to show the The primary purpose was to show the wealth of the new dynasty of the wealth of the new dynasty of the time.time.

They gave away things they did not They gave away things they did not pillage like the Vikings and the pillage like the Vikings and the Spanish.Spanish.

They wanted to show they were the They wanted to show they were the only truly civilized people on earth.only truly civilized people on earth.

Invented central rudder, watertight Invented central rudder, watertight compartments, multiple masts and compartments, multiple masts and sophisticated sails. sophisticated sails.

The chinese abndiopnded ocean The chinese abndiopnded ocean exploration in 1433. The cost was to exploration in 1433. The cost was to high. high.

The age of DiscoveryThe age of Discovery

Prince Henry the Navigator 1451-Prince Henry the Navigator 1451-1470 strong supporter of sea 1470 strong supporter of sea voyages (gave them compasses)voyages (gave them compasses)

Christopher ColumbusChristopher Columbus Ferdinand MagellanFerdinand Magellan James CookJames Cook John HarrisonJohn Harrison Sir John RossSir John Ross

Lt. Charles WilkesLt. Charles Wilkes Matthew MauryMatthew Maury Charles DarwinCharles Darwin Alfred Thayer MahanAlfred Thayer Mahan Fridtjof NansenFridtjof Nansen Robert E. PearyRobert E. Peary Captain William AndersonCaptain William Anderson

SCICEXSCICEX Meteor ExpeditionMeteor Expedition Tpoex/PoseidenTpoex/Poseiden JAMSTECJAMSTEC Jason 1Jason 1 SEASTARSEASTAR AquaAqua GPSGPS

II. Word oceans - II. Word oceans - Covers 70.8% of the surface Covers 70.8% of the surface of the Earth to a mean depth of 4kmof the Earth to a mean depth of 4km

A. Major ocean basins (fig 2.1)A. Major ocean basins (fig 2.1) 1. Pacific - almost as large as all others combined, 1. Pacific - almost as large as all others combined,

but shrinkingbut shrinking 2. Atlantic - growing2. Atlantic - growing 3. Indian - strongest winds, largest waves3. Indian - strongest winds, largest waves 4. Arctic - ice covered year round4. Arctic - ice covered year round 5. Southern ocean - sum of all other ocean basins 5. Southern ocean - sum of all other ocean basins

surrounding Antarctica - not really an ocean (fig. surrounding Antarctica - not really an ocean (fig. 1.2)1.2)

6. Seas/gulfs6. Seas/gulfs

B. Oceanic climactic regions B. Oceanic climactic regions (figs)(figs)

- regional winds and precipitation - regional winds and precipitation (global climate) due to intertropical (global climate) due to intertropical convergence and Hadley cells, which convergence and Hadley cells, which I will not cover in detail in this I will not cover in detail in this course, but you should be familiar course, but you should be familiar with the regional winds and with the regional winds and precipitation levels/salinity)precipitation levels/salinity)

1. 1. EquatorialEquatorial - 0° to 10° N/S of - 0° to 10° N/S of equatorequator

a. Doldrumsa. Doldrums b. Low salinity waters due to b. Low salinity waters due to

high precipitationhigh precipitation

2. 2. TropicalTropical - 10° N/S to 23°N/S - 10° N/S to 23°N/S a. Tradewinds - NE in north, SE in a. Tradewinds - NE in north, SE in

southsouth b. Hurricanes/Typhoons b. Hurricanes/Typhoons

(Atlantic/Pacific) severe seasonal (Atlantic/Pacific) severe seasonal cyclonic storms that transfer lots of cyclonic storms that transfer lots of heat and precipitation into the heat and precipitation into the subtropical regions subtropical regions

c. Monsoons - seasonal wind shifts c. Monsoons - seasonal wind shifts and heavy rains in Indian Oceanand heavy rains in Indian Ocean

(not cyclonic, active for a whole season)(not cyclonic, active for a whole season)

3. 3. SubtropicalSubtropical - 23° N/S of equator to - 23° N/S of equator to approx 40° N/Sapprox 40° N/S

a. Dry, high pressure, little windsa. Dry, high pressure, little winds b. High salinity watersb. High salinity waters

4. 4. TemperateTemperate - 40° N/S - 60° N/S - 40° N/S - 60° N/S a. Westerly winds(SW in N and a. Westerly winds(SW in N and

NW in S)NW in S)

5. 5. SubpolarSubpolar - 60° N/S -80° N/S - 60° N/S -80° N/S a. Winter - ice, summer - open watera. Winter - ice, summer - open water b. Surface temps rarely above 5°Cb. Surface temps rarely above 5°C c. High salinity - due to freezing - salt c. High salinity - due to freezing - salt

leaves water as it freezes, being leaves water as it freezes, being forced in to the surrounding water forced in to the surrounding water making it more saline.making it more saline.

6. Polar >80° N/S6. Polar >80° N/S a. Ice covereda. Ice covered b. Lightless polar winters b. Lightless polar winters - due to 23° axial tilt of Earth (also - due to 23° axial tilt of Earth (also

reason for seasons)reason for seasons) - show sun clock images- show sun clock images i. Arctic - no sunlight Dec - Febi. Arctic - no sunlight Dec - Feb ii. Antarctic - no sunlight Jun - Augii. Antarctic - no sunlight Jun - Aug

C. Seasonality of oceanic C. Seasonality of oceanic temperatures - figstemperatures - figs

- ocean temperatures vary - ocean temperatures vary seasonally, as do air temperatures, seasonally, as do air temperatures, due to the axial tilt of the earthdue to the axial tilt of the earth

- you can see the shift in warm - you can see the shift in warm temps from sorth of the equator temps from sorth of the equator during June to south of it in during June to south of it in DecemberDecember

C. Seasonality of oceanic temperaturesC. Seasonality of oceanic temperatures- - ocean temperatures vary seasonally, as do air ocean temperatures vary seasonally, as do air temperatures, due to the axial tilt of the earthtemperatures, due to the axial tilt of the earth

- you can see the shift in warm temps from south - you can see the shift in warm temps from south of the equator during June to south of it in of the equator during June to south of it in DecemberDecember

(fig - surface temp images from internet) (fig - surface temp images from internet) a. Warm water from equator N and S (Gulf a. Warm water from equator N and S (Gulf

stream) - effects climate of Northern Europestream) - effects climate of Northern Europe b. Cold water return - deep b. Cold water return - deep

currents/upwelling - effects climate of currents/upwelling - effects climate of shorelines, shorelines,

e.g. California (dry) and West. S.A.e.g. California (dry) and West. S.A.