7 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.
8 Where did the Water Come From? Volcanism and OutgassingMantle produced early atmospheric rich gasesEarth cooled and water condensed and oceans formedSee Pg 30 “Origin of theOceans”Extraterrestrial in Origin?
10 Boxed Reading: Origin of the Oceans Age of Earth: approximately 4 billion yearsWater from interior of EarthMantleGas that escape volcanoes is 70% water vapor4 billion years at current rate 100 times the volume of the oceansWater from outer space10 million comets enter the atmosphere each yearLayer of water mm deep added each year4 billion years at current rate 2 to 3 times the volume of the oceans
13 Dissolved salts in sea water (atoms): Introduction:Ocean70% of Earth is Water97% of waterModerates 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 saltLive in water for 9 monthsFormed by trapped water vaporCooled and then condensedDissolved salts in sea water (atoms):55.3 % Chlorine30.8 % Sodium3.7 % Magnesium2.6 % Sulfur1.2 % Calcium1.1 % Potassium
14 Earth’s Water 2.6 Reservoirs and residence time Large reservoirs long residence timeSmall reservoirs short residence timeDistribution of land and waterNorthern Hemisphere (land)Southern Hemisphere (water)OceansHypsographic curve
23 Location of Position on Earth Latitude- Imaginary gridlines on Earth that run east to west.Known as parallelsEquator = 0°Poles = 90°N and 90°SLongitude- 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 = -
24 Location Systems 2.4 Latitude and longitude Chart and maps Latitudes (or parallels) are parallel to the equatorLongitudes (or meridians) are formed at right angles to the latitude linesPrime meridian and international date lineGreat CircleNautical mileChart and mapsDistorted images of Earth’s curved surfaceProjection types: cylindric, conic, and tangent
25 2.4 con’t Measuring latitude Longitude and time North Star, Polaris Use of clocks to record the time the Sun is at its zenithGreenwich Mean Time (GMT) or Universal Time
30 Measuring Longitude Difficult!! Needed Chronometer 15° = 1 hour Clocks didn’t keep accurate time on ships! Why?15° = 1 hourReference longitude = Prime meridianGreenwich Mean Time GMTNow called Universal Time UT or Zulu Time for Zero MeridianTime zones15° of longitude wide
33 Identification of Point on Earth’s Surface Crossing of Latitude and Longitude158°W, 21°N = Hawaiian Islands20°E, 33°S = Cape of Good Hope41.473°N, °W = Shaker Heights, Ohio1° Latitude = 60 Nautical Miles1° of arc = 60’ minutes of arc1’ of arc = 60” seconds of arc( °, ', " )Shaker Heights is at41° 47’ (minutes) 3” (seconds)
34 The Nautical Mile / Sea Mile Measurement of Length1 NM ~ 1.8 km = 1.15 mi1NM = 1’ of latitude
35 Finding Distances Between Locations Length of between longitudes at equator = 69.2 miLength of between longitudes at 80° = mi0 mi at the polesLength of a degree of longitude =cos (latitude) * 69.2 milesEX 1 degree of longitude at 40°Distance = cos (40) * 69.2 miles= * 69.2
38 Modern National Techniques 2.5 Radar (radio detecting and ranging)Loran (long-range navigation)Satellite navigation systemGlobal Positioning System (GPS)Shipboard computersElectronic atlasSurface chartsBathymetryContinuous tracking of ship’s position
39 Charts and Maps 2.4 Topographic Maps (topography) Maps that show lines connecting points of similar elevationBathymetric Maps (bathymetry)Charts of the ocean showing contour lines connecting points of the same depth below the sea surfacePhysiographic MapsColor, shading, and perspective drawings may be added to simulate topography and produce visual representations or bird’s-eye views
44 The Water Planet Distance from the Sun = 93 million miles Earth’s mean surface temperature = 16° C (61 °F)What protects Earth from temperature extremesModerated by rotation of Earth on axisAtmospheric Gases act like blanketOrbit of Earth around SunAll 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
49 Residence TimeAverage Length of time that a water molecule spends in any one reservoirWater is replaced in the atmosphere about 29 times every year13,000 km3 of water in atmosphere at any one timeEvaporation from ocean/landOcean = 320,000 km3Land = 60,000 km3Precipitation returned from ocean/landOcean = 284,000 km3Land = 96,000 km3Excess runs off to rivers, streams, ocean and ground water
61 Origins 13 b.y.a big bang 5 b.y.a 4.6 b.y.a. 3.5 b.y.a 3.4 – 3.5 b.y.a Mass and energy of the universe is thought to have been concentrated at a geometric point at the beginning of timeMoment of expansionOrigin of galaxies5 b.y.aFormation of our Solar System4.6 b.y.a.Formation of Earth3.5 b.y.aFormation of water vapor, atmosphere3.4 – 3.5 b.y.aComplex bacteria fossils
62 Origins 2.1 Origin of the universe Origin of our solar system Hubble Space Telescope (HST)Big Bang modelStars, galaxies, and clustersOrigin of our solar systemCollapse of a rotating interstellar cloudAccretion to form planets
63 2.1 con’t. Extraterrestrial oceans Early planet Earth Liquid oceans on Jupiter’s moons, Europa and CallistoEarly planet EarthSeparation of dense and lighter compounds through repeated melting and solidifying layered system, ocean, and atmosphereNo free oxygen until photosynthetic organisms evolved
69 Age and Time 2.2 Age of Earth Geologic time Natural time periods History of estimatesBible, cooling time, rate of addition of salt in oceans by rivers, radiometric datingRadiometric dating billion yearsGeologic timeEons, eras, periods, epochsImportant eventsNatural time periodsTime required for Earth to complete one orbit around the SunLength of day and seasonsLunar monthSolar daySidereal day
72 Shape of Earth 2.3 Gravity Spin Distribution of continents Earth is nearly sphericalSpinEarth bulges at equatorDistribution of continentsSlightly pear shapedTopographic reliefMinor compared to planet’s size
73 Biosynthesis Evolution of early life 1950’s Evaporation of water lead to concentration of amino acids in coastal tidal poolsSunlight = energy for rxnsNow this theory is put aside researchers don’t think the sun was bright enough for rxns to take placeIsotopes- Atoms of the same element having different # of neutrons.Although this theory was debunked, Oceans are where scientist think life started on Earth
74 Summary of Chapter 2 Expansion of universe First stars produced the elements and galaxiesRadiometric datingLatitude and longitudeGrid systemClocksModern navigational techniquesRadar, radio signals, computers, satellitesHydrological cycleReservoirs and residence time
75 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.
76 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.
77 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.
78 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.
79 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 ° 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.
80 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
81 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.
82 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.
83 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.
84 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).
85 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.
86 Homework Within Chapter 2 - Book Read chapter2Write out Vocab Terms 10 timesRewrite PPT notes 10 times
87 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.
88 What is biosynthesis? Where do researcher think it might have occurred on our planet? Could it happen again today?
89 Critical Thinking Questions Marine 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?
90 CitationsArmbrust,V., Sverdrup,K. An Introduction to the World’s Oceans McGraw-Hill. Chapter 2.