Oceanography

Last Updated 2013 Miss Rabatin

WaterWorld…

What % of H20is in the Ocean?

Where is the Water?

Salinity of Oceans, What in there???

Surface of Salinity

As water travels through the water cycle, some water will become part of The Global Conveyer Belt and can take up to 1,000 years to complete this global circuit. It represents in a simple way how ocean currents carry warm surface waters from the equator toward the poles and moderate global climate.

Where did the Water Come From?

Volcanism and Outgassing

Mantle produced early atmospheric rich gasesEarth cooled and water condensed and oceans formedSee Pg 30 “Origin of the

Oceans” Extraterrestrial in Origin?

Boxed Reading: Origin of the OceansAge of Earth: approximately 4 billion years Water from interior of Earth

Mantle Gas that escape volcanoes is 70% water vapor4 billion years at current rate 100 times the volume of the oceans

Water from outer space10 million comets enter the atmosphere each yearLayer of water 0.0025 mm deep added each year4 billion years at current rate 2 to 3 times the volume of the oceans

World’s Ocean’s

Introduction:Ocean

70% of Earth is Water 97% of water

Moderates Temp. and Weather1/3 of PetroleumLife in ocean for 3 b.y. before coming to landWe are made of water

% of salt in our bodies proportional to ocean salt Live in water for 9 months

Formed by trapped water vapor Cooled and then condensed

Dissolved salts insea water (atoms):

55.3 % Chlorine

30.8 % Sodium

3.7 % Magnesium

2.6 % Sulfur

1.2 % Calcium

1.1 % Potassium

Earth’s Water 2.6Reservoirs and residence time

Large reservoirs long residence timeSmall reservoirs short residence time

Distribution of land and water Northern Hemisphere (land) Southern Hemisphere (water)

OceansHypsographic curve

Biological Oceanography

Light Causes the Food Chain

Physical Oceanography

World’s WaterN. Hemisphere

60.7% Sea 39.3% Land

S. Hemisphere80.9% Sea19.1% Land

Ocean’s Deepest Spot?Mariana Trench 11,022 m

Pacific OceanGoogle Earth

Northern Hemisphere

Southern Hemisphere

Location of Position on EarthLatitude- Imaginary gridlines on Earth that run east to west.

Known as parallels Equator = 0°Poles = 90°N and 90°S

Longitude- Imaginary gridlines on Earth that run north to south.Known as MeridiansPrime Meridian = 0°International Date Line = 180°Lines East of PM = +Lines West of PM = -

Location Systems 2.4Latitude and longitude

Latitudes (or parallels) are parallel to the equatorLongitudes (or meridians) are formed at right angles to the latitude lines

Prime meridian and international date line

Great CircleNautical mile

Chart and mapsDistorted images of Earth’s curved surfaceProjection types: cylindric, conic, and tangent

2.4 con’tMeasuring latitude

North Star, Polaris

Longitude and time Use of clocks to record the time the Sun is at its zenithGreenwich Mean Time (GMT) or Universal Time

Measuring LatitudeMeasure the angle between the horizon and polaris (the north star)

                                                                                                                                            

           

http://www.pbs.org/weta/roughscience/series1/challenges/latlong/page3.html

Measuring LongitudeDifficult!!Needed Chronometer

Clocks didn’t keep accurate time on ships! Why?

15° = 1 hourReference longitude = Prime meridian

Greenwich Mean Time GMT Now called Universal Time UT or Zulu Time for Zero Meridian

Time zones 15° of longitude wide

http://toi.iriti.cnr.it/img/timezone.gif

Identification of Point on Earth’s SurfaceCrossing of Latitude and Longitude

158°W, 21°N = Hawaiian Islands20°E, 33°S = Cape of Good Hope41.473°N, -81.537°W = Shaker Heights, Ohio

1° Latitude = 60 Nautical Miles1° of arc = 60’ minutes of arc1’ of arc = 60” seconds of arc

( °, ', " ) Shaker Heights is at 41° 47’ (minutes) 3” (seconds)

The Nautical Mile / Sea MileMeasurement of Length1 NM ~ 1.8 km = 1.15 mi1NM = 1’ of latitude

http://content.answers.com/main/content/wp/en-commons/7/79/Nautic_mile_definition_v2.png

Finding Distances Between Locations

Length of between longitudes at equator = 69.2 miLength of between longitudes at 80° = 10.47 mi0 mi at the polesLength of a degree of longitude =

cos (latitude) * 69.2 miles

EX 1 degree of longitude at 40°Distance = cos (40) * 69.2 miles

= .7660 * 69.2

Modern National Techniques 2.5Radar (radio detecting and ranging)Loran (long-range navigation)Satellite navigation systemGlobal Positioning System (GPS)Shipboard computers

Electronic atlas Surface charts Bathymetry Continuous tracking of ship’s position

Charts and Maps 2.4Topographic Maps (topography)

Maps that show lines connecting points of similar elevation

Bathymetric Maps (bathymetry)Charts of the ocean showing contour lines connecting points of the same depth below the sea surface

Physiographic Maps Color, shading, and perspective drawings may be added to simulate topography and produce visual representations or bird’s-eye views

Topographic Map

http://www.jesseshunting.com/images/topo-bench-saddle1.jpg

Bathymetric Map

Physiographic Map

The Water PlanetDistance from the Sun = 93 million milesEarth’s mean surface temperature = 16° C (61 °F)What protects Earth from temperature extremes

Moderated by rotation of Earth on axisAtmospheric Gases act like blanketOrbit of Earth around Sun

All of the above allow earth to have liquid water!Ocean’s cover 362 million km2 (140 million mi2)71% waterVolume of Ocean’s are 1.35 billion km3

Where’s the WaterOceanRiverLakesGround waterGlaciersVapor in atmosphereReservoir - place where water resides

Movement though the water reservoirs = hydrologic cycle

Hydrologic Cycle

Residence TimeAverage Length of time that a water molecule spends in any one reservoirWater is replaced in the atmosphere about 29 times every year

13,000 km3 of water in atmosphere at any one timeEvaporation from ocean/land

Ocean = 320,000 km3

Land = 60,000 km3

Precipitation returned from ocean/landOcean = 284,000 km3

Land = 96,000 km3

Excess runs off to rivers, streams, ocean and ground water

Hypsographic Curve

Seasons

Equinox’s

Scientific MethodUsing logical, systematic methods to investigate the world

Examples: Einstein's Theory of General Relativity Plate Tectonics Evolution Newton’s Law’s

HypothesisProposal intended to explain certain facts or observations

Tentative explanationTestableSpeculation about the worldQuestion

TheoryWell-substantiated explanation of some aspect of the natural world Examples:

Einstein's Theory of General Relativity

Plate Tectonics Evolution

LawSet of observed regularities expressed in a concise verbal or mathematical statementExamples

Newton’s LawsLaw of reflectionArchimedes PrincipleArchie’s Law

Origins13 b.y.a big bang

Mass and energy of the universe is thought to have been concentrated at a geometric point at the beginning of timeMoment of expansionOrigin of galaxies

5 b.y.aFormation of our Solar System

4.6 b.y.a.Formation of Earth

3.5 b.y.a Formation of water vapor, atmosphere

3.4 – 3.5 b.y.aComplex bacteria fossils

Origins 2.1Origin of the universe

Hubble Space Telescope (HST)Big Bang modelStars, galaxies, and clusters

Origin of our solar systemCollapse of a rotating interstellar cloudAccretion to form planets

2.1 con’t.Extraterrestrial oceans

Liquid oceans on Jupiter’s moons, Europa and Callisto

Early planet Earth Separation of dense and lighter compounds through repeated melting and solidifying layered system, ocean, and atmosphereNo free oxygen until photosynthetic organisms evolved

Elements in Universe

Age and Time 2.2Age of Earth

History of estimates Bible, cooling time, rate of addition of salt in oceans by rivers, radiometric dating

Radiometric dating 4.5-4.6 billion yearsGeologic time

Eons, eras, periods, epochsImportant events

Natural time periodsTime required for Earth to complete one orbit around the SunLength of day and seasonsLunar monthSolar daySidereal day

Shape of Earth 2.3Gravity

Earth is nearly spherical

Spin Earth bulges at equator

Distribution of continentsSlightly pear shaped

Topographic relief Minor compared to planet’s size

BiosynthesisEvolution of early life1950’sEvaporation of water lead to concentration of amino acids in coastal tidal poolsSunlight = energy for rxns

Now this theory is put aside researchers don’t think the sun was bright enough for rxns to take place

Isotopes- Atoms of the same element having different # of neutrons.Although this theory was debunked, Oceans are where scientist think life started on Earth

Summary of Chapter 2Expansion of universeFirst stars produced the elements and galaxies Radiometric datingLatitude and longitude

Grid systemClocks

Modern navigational techniquesRadar, radio signals, computers, satellites

Hydrological cycleReservoirs and residence time

Vocab TermsOcean- Single entity, subtly different characteristics at different locations.Marine Science/Oceanography- Applying the scientific method to study the ocean, its surroundings, and the life forms within it.Science- Systematic process of asking questions about the observable world and then testing the answers to those questions.

Hypothesis- Speculation of the natural world that can be tested and verified or disproved by further observations and controlled experiments.Theory- Statement of relationship accepted by most scientist.Laws- Principles explaining events in nature that have been observed to occur with unvarying uniformity under the same conditions.Outgassing- Volcanic venting of volatile substances including water vapor.Biosynthesis- Popularized in the 50’s, life may have originated in shallow tidal pools at the ocean’s edge.

Electromagnetic Spectrum- Waves of energy formed by simultaneous electrical and magnetic oscillations; the spectrum is all the radiation from low to high energy.Big Bang- A widely accepted view of how the universe was created. Accepted age of universe 13.7 billion years old.Galaxy- Huge aggregate of stars held together by mutual gravitation.Light year- Distance light travels in 1 year = 9.46 E12 km or 5.87 E12 mi.Nebula- Large dense cloud of gas and dust in spaceIsotope- Atoms of the same element having different numbers of neutronsHalf-Life- Time required for half o an initial quantity of a radioactive isotope to decay.

Vertebrates- Animals with backbones or spinal columns.Tropic of Cancer/Capricorn- Latitudes 23 ½ º N and 23 ½ º S respectively, marking the max angular distance of the Sun from the equator during the summer and winter solstice.Summer Solstice- Time of the year when the Sun stands directly above 23 ½ º N and 23 ½ º S latitude. Around June 22.Artic/Antarctic Circle- Latitudes 66 ½ º N and 66 ½ º S, marking the boundaries of light and darkness during the summer and winter solstices.Autumnal Equinox- Days of the year when the Sun stands directly above the equator, so that the day and night are equal length around the world. This occurs about march 21st, and September 23rd.

Lunar Month- Time required for the Moon to pass from one new Moon to another new Moon (approx. 29 days).Solar Day- Time period determined by one rotation of the Earth relative to the Sun; the mean solar day is 24 hours.Sidereal Day- Time period determined by one rotation of the Earth relative to a far-distant star, about four minutes shorter than the mean solar day.Latitude- Distance north or south of the equator. Latitude is the angle between the equatorial plane and a line drawn outward from the center of Earth to a point on the surface. Latitude varies from 0° to +90 ° north of the equator and -90 ° south of the equator.Longitude- Distance east or west of the prime meridian. Longitude is the angle in the equatorial plane between the prime meridian and a second meridian that passes through a point on the surface of Earth whose location is being specified.

Parallels- Circle on the surface of the Earth parallel to the plane of the equator and connecting al points of equal latitude; a line of latitude.Equator- 0º latitude, determined by a plane that is perpendicular to Earth’s axis and is everywhere equidistant from the North and South Poles.Meridians- Circle of longitude passing through the poles and any given point on Earth’s surface.Prime Meridian- Meridian of 0 º longitude, us3ed as the origin for measurements of longitude; internationally accepted as the meridian of the Royal Naval Observatory, Greenwich, England

International Date Line- An imaginary line through the Pacific Ocean roughly corresponding to 180 º longitude, to the east of which by international agreement, the calendar date is one day earlier than the west.Great Circle- The intersection of a plane passing through the center of Earth with the surface of Earth. Great circles are formed by the equator and any two meridians of longitude 180 º apart.Nautical Mile- Unit of length equal to 1852 m, or 1.15 and miles or 1 minute of latitude.Contours- line on a chart or graph connecting points of equal elevation, temperature, salinity, or other property.

Topography- General elevation pattern of the land surface.Bathymetry- Study and mapping of seafloor elevations and the variations of water depth; topography of the sea floor.Polaris- also known as the North Star, is located less than 1 º from the celestial pole, a line corresponding to the extension of Earth’s axis of rotation into the sky from the north geographic pole. The angular elevation of Polaris above the horizon corresponds to the latitude of an observer in the northern hemisphere.Zenith- Point in the sky that is immediately overhead.Greenwich Mean Time (GMT)/Universal Time/Zulu time- solar time along the prime meridian passing through Greenwich, England.

Reservoir- A source or place of temporary residence for water; such as the oceans or atmosphere.Hydrologic Cycle- Movement of water among the land, oceans, and atmosphere due to vertical and horizontal transport, evaporation, and precipitation.Transpiration- Process by which plants return moisture to air. Plants take up water through roots and lose water through pores in their leaves. An actively growing plant daily transpires five to ten times as much water as it holds at one time.Sublimation- Transition of a substance from its solid state to its gaseous state without becoming a liquid.

Residence Time- Mean time that a substance remains in a given area before being replaced, calculated by diving the amount of a substance by its rate of addition or subtraction.Hypsographic Curve- Graph of land elevation and ocean depth versus area.Mean Earth Sphere Depth- Depth below sea level of the surface of the solid Earth if it was perfectly smooth with no variation in elevation. This is 2403 m (7884 ft) below present sea level.Mean Ocean Sphere Depth- Depth of the ocean if the solid Earth was perfectly smooth with no variation in elevation. This is 2646 m (8682 ft).

Global Position System- a worldwide radio-navigation system consisting of twenty-four navigational satellites and five ground-based monitoring stations. GPS uses this system of satellites as reference points for calculating accurate positions on the surface of Earth with readily available GPS receivers.Universal Time- Solar time along the prime meridian passing through Greenwich, England; aka Greenwich Mean Time (GMT) or Zulu Time.

Homework Within Chapter 2 - BookRead chapter2Write out Vocab Terms 10 timesRewrite PPT notes 10 times

Review QuestionsWhich hemisphere contains the greatest percentage of ocean? Is most of Earth’s water in the ocean?Can the scientific method be applied to speculations about the natural world that are not subject to test or observation.What element makes up most of the detectable mass in the universe.

What is biosynthesis? Where do researcher think it might have occurred on our planet? Could it happen again today?

Critical Thinking QuestionsMarine biologists sometimes say that all life forms on Earth, even desert lizards and alpine plants, are marine. Why?Where did Earth’s surface water come from?How do we know what happened so long ago?

CitationsArmbrust,V., Sverdrup,K. An Introduction to the World’s Oceans. 2008. McGraw-Hill. Chapter 2.http://content.answers.com/main/content/wp/en-commons/7/79/Nautic_mile_definition_v2.pnghttp://www.pbs.org/weta/roughscience/series1/challenges/latlong/page3.htmlhttp://toi.iriti.cnr.it/img/timezone.gifhttp://www-istp.gsfc.nasa.gov/stargaze/Slatlong.htmhttp://www.ec.gc.ca/water/images/nature/grdwtr/a5f5e-rev.gifhttp://apollo.lsc.vsc.edu/classes/met130/notes/chapter3/graphics/equinox.jpg