Water_ Waves_ and Tides by chenmeixiu


									Water, Waves, and
Water, Waves, and Tides Terms
                          Global warming
   Adhesion
                          Halocline*
   Breaker
                          Hydrogen bond
   Capillary action
                          Mixed semidiurnal tide
   Capillary wave
                          Neap tide
   Deepwater wave
                          Northeast trade winds
   Diurnal tide*
                          Oxygen minimum
   Eastern boundary
                          Period
   Ebb tide
                          Progressive wave
   Ekman spiral*
                          Tide
   Salinity
                          Tidal current*
   Semidiurnal wave
                          Western boundary
   Spring tide*
   Because water covers approximately
    71% of the earths surface, it may
    seem that there would be so much
    water available that the way water is
    used would not be an issue. Water is
    actually NOT that easy to get and
    use for human purposes. Most water
    on earth cant be used directly for
    drinking, irrigation, or industry for
    the simple reason that most of it is
        Human usage of water
   Humans primarily need fresh water. There
    unfortunately just not as much around as
    we would like.
   Plenty of water can be found at the poles,
    but most if frozen and located far away.
   We can condense water from the
    atmosphere by artificial means, but only
    at an astounding cost.
   Most freshwater we get comes from
    underground streams and aquifers and
              Gases in water
   A main gas in seawater is Carbon Dioxide,
    CO2. It is prevalent due to photosynthesis
    from bacteria, algae, plankton etc. It
    produces oxygen as a by-product. Most living
    organisms require oxygen and produce CO2.
   To decompose an organism, respiration is
    required, and this also contributes O2 and
    CO2 to the water.
   Where oxygen is low in the marine
    environment- depleted naturally thru animal
    life/respiration, you will find the oxygen-
    minimal zone (just below the sunlit water
    surface). CO2 is often high here however,
    because it is added by those using up all the
        Gas Solubility in seawater

   O2 and CO2 is higher in surface seawater than it is in the
    atm. N is less.
   Combining CO2 with seawater allows the seawater to hold
    more CO2 than the other two gases.
   Acid- a solution that contains high number of hydrogen ions
    than hydroxyl.
   Base- a solution (alkaline) that has more hydroxyl ions than
   pH- a scale of 0-14 that measures the degree of acidity of a
   Examples: 1-gastric juice, 3 vinegar, 5 urine, 7 saliva, 11
    soap, 13 milk. Lower the #, stronger the acid. Higher #=
    stronger base.
             Latitude and Longitude
   To locate areas with precision, people draw a grid, or
    series of lines, over maps and globes. The equator is
    a vital line on this grid, it divides the world in half- the
    northern and southern hemisphere.
   The SH has 20% more ocean than the NH.
   Lines that run parallel to the equator are called lines
    of Latitude. Distances north or south of the equator
    are measured in degrees. Lat of eq is 0 degrees. Lat
    of N. Pole is 90 degrees N. The Lat of the S. Pole is 90
    deg. S.
   Longitude combines latitude measurements to find
    pinpoint locations. These lines run from NP to SP and
    intersect the lines of latitude. Longitude is measured
    in degrees east or west of the prime meridian, which
    runs thru Greenwich, England and that is the starting
    point of longitude. 0 degrees. Earth is divided into 24
    meridians, meridians are 15 degrees apart. Meridians
    cover 180 deg. E and W of the prime meridian.
    Location is given in precise statements. Example:
    Galapagos Islands are located at 85 deg. West
    Longitude. 0 deg. Latitude.
   The ocean surface water has about 10%
    that is involved in currents. Currents move
    the upper layers of the water, down to
    about 400m. Many organisms are carried
    by the currents. Because many organisms
    are carried by current, this also effects
    how predators move and follow their prey
    as well.
   Factors like El Nino, can greatly effect
    currents as phenomenon like that, have a
    large effect on our ocean systems.
   Wind is the result of horizontal air
    movements caused by temp. and
    density. Warm air=density
    decreases=air rises. Cool air=density
    increases=air falls. Density of air is
    determined by its temp, vapor, and
    atm. Pressure.
                Coriolis Effect
   What causes ocean currents to move in
    certain directions? The circular drift of oceans
    was first studied by the French Physicist
    Gaspard Coriolis (1792-1843). His findings
    are called the Coriolis Effect. It states that
    the spinning of earth causes winds and
    surface waters to move in a clockwise
    direction in the NH and in a CCW direction in
    the SH. The continents deflect the ocean
    currents, causing them to move in giant
    circles called SURFACE CURRENTS. These are
    important to marine life because they move
    drifting plankton thousands of km across the
   Answer this in your notes: What
    causes global ocean currents
    (surface) and RELATE this to Global
    warming. Please provide explanation
    and example.

   Western boundary currents- fastest/deepest of
    currents; found along western boundaries of
    ocean basins. Move warm water toward poles.
    Gulf Stream is largest of these currents. Moves at
    speed of about 5 miles per hour. ( 2m per sec)
   Eastern boundary currents- opp. Of west bound
    currents. Carry cold water toward equator. Slow.
    6-12 miles per day. Volume of water of these
    currents is small. Very wide currents.
   Transverse currents- E and W boundary currents
    are connected by transverse currents. Current
   WBC carry little in way of nutrients cause they
    move fast and with lots of water. Not really a
    productive current. Fast water does make for
    more O2 in the water however. EBC move slow
    so they are very productive and nutrient rich.
          Sub-surface currents
   Winds at the surface continues to force its
    way down deeper and deeper, indirectly
    cause more currents at greater depths.
    The surface movement causes water to
    move beneath it and so forth, cause
    currents to travel down. This movement of
    deep water is deflected to the right in the
    NH and to the left in the SH. This keeps
    effecting all layers of the water due to the
    friction it causes. Each layer slides over
    the other layer horizontally, the spiral
    pattern this causes is known as the Ekman
                 WARM UP
   1) Would it be easier for a planktonic
    organism to float in water with a high
    salinity or a low salinity? Explain
   2) How would photosynthesis and
    respiration play a role in the distribution of
    marine organisms? Explain
   3) Explain the navigation/map system we
    use. Include terms about latitude,
    longitude, prime meridian, equator.
           Depth Variations
   Temp’s of the ocean, vary with
    depth, especially in the middle
    latitudes. Typically, the deeper you
    descend, the colder/cooler it gets.
    The decrease is not uniform
    however. There is a very steep drop
    between 200-1000 meters. This
    ocean layer is called the thermocline-
    a permanent boundary that
    separates warmer water above from
    the colder, denser water below.
        Seasonal Thermocline
   A seasonal thermocline between
    100-200 meters deep can also occur.
    This is more common in summer,
    when water is heated more by the
    sun. Because of this, the surface
    water is less dense than the cold
    water below, so it floats on top of the
    distinct layer. To get a temperature
    profile of the ocean, oceanographers
    use a bathythermograph, a reversing
    thermometer, and thermistors.
      Halocline and Pycnolcline
   Halocline is a zone below surface waters
    to about 1000 m in depth where salinity
    increases. The change in temp and
    salinity in this region from 100-1000m
    produce a pycnocline, a zone where
    density rapidly increases with depth.
    Thermocline, halocline, and pycnocline are
    permanent ocean features because they
    are too deep to be effected by the mixing
    action of winds.
   The tide is the daily rise and fall of the ocean
    along the shore. High tide is the oceans highest
    point, low tide, the lowest. The vertical distance
    between the low and high tides is called the tidal
    range. This range varies depending on the shape
    of the coastline. Typically 1-2 m high on the east
    coast, but in Canada’s Bay of Fundy, a boat
    docked at a pier may rise as much as 20m from
    low to high tide. This bay has a high tidal range.
    The time between high and low tides is about 6
    hours and 20 minutes. (varies slightly per
   SPRING TIDE- the highest and lowest tides,
    produced twice each month by strong
    gravitational pull when sun, moon, and earth
   NEAP TIDE- weaker tides ( not to high or too low)
    produced twice each month.
              Key Points- WWT
   The tide is the daily predictable rise and fall of sea
    level and is the most important factor influencing life
    in the intertidal zone.
   Tides are formed due to the interaction of the
    gravitational attraction of the sun and moon on the
    earth and the centrifugal force generated by the
    rotating earth-moon system.
   Extreme spring tides occur when the sun and moon
    are directly aligned, whereas minimal neap tides occur
    when the sun and moon are at right angles to each
   Differences in the # of high and low tides per day and
    in their heights are due to the peculiarities of the
    basins in which the tides occur.
   Tides with a single high and low per day are diurnal,
    tides with 2 H and 2 L per day are semidiurnal.
               KEY CONCEPTS- Ct’d
   Tides can have 2 direct effects on organisms. The first involves
    the duration of exposure to the air. Since the organisms are
    primarily marine, the longer they are exposed to air, the
    greater is the chance that they will become desiccated beyond
    their limits of tolerance or that they will encounter a lethal
    temperature. Intertidal organisms differ in their tolerance to
    exposure and this difference contributes to their patterns of
   The second effect is the result of the time of day that exposure
    to air occurs. Exposure to air during midday in the tropics
    could lead to lethal temperatures; exposure at night in cold
    temperate zones in winter could lead to the organisms freezing
    to death.
   The great predictability of tides induces certain rhythms, such
    as feeding and reproduction, in intertidal organisms.
   Air temps always have a greater range than water temps and
    extremes may either kill organisms or weaken them, making
    them susceptible to death by other factors, such as
   Wave action directly affects organisms in 2 ways. First, on
    sedimentary shores it moves entire substrate around,
    smashing org. and tearing them apart. Second, waves throw
    water higher on the shore than the water level due to tides;
    therefore, wave action allows marine organisms to live higher
    than the tides would permit them to.
   Wave Terms:         Types of Waves
   Crest               Ripple
   Trough              Chop
   Wave Length         Sea
   Wave Height         Swell
   Wave Period         Surf Beat
   Wave Frequency      Tsunamis
                        Tides
         Wave History- Studies
   1802- Franz Gerstner       1825- Ernst and
   Studied water               Wilhelm Weber
    particles in waves=        Used a wave channel
    move in circles             to study waves- filled
   Surface trace of a          it with a variety of
    wave is approximately       liquids (mercury,
    a trochoid (like sine       water, alcohol, etc)
    waves)                     3 important
                                discoveries: 1) waves
                                reflected with no
                                energy loss. 2)
                                suspended particles
                                trace circles in wave.
                                3) near bottom orbits
                                are nearly flat.
    Wave Height and Wind Related
   Wave Height: Appears        Orbital motion:
    at first to be               Movement of water
    independent of wave          molecules studied
    period and length.           found that molecules
   Repeated experiments         travel in circular
    show that wave crest         motion in waves.
    angle cannot be more        Surface particles make
    that 120 degrees.            orbit=wave height,
   FACTORS                      deeper orbits are
    DETERMINING WAVE             progressively smaller.
    DEVELOPMENT: 1)              Deep orbits become
    Wind velocity 2)             more and more
    length of time wind          flattened.
    blows 3) Length of          At bottom, the
    fetch 4) wind is never       particles simply move
    constant 5) erratic          back and forth.
    wind direction shifts
            Wave/Water Facts

   Water covers about 71% of Earth’s
   Vast majority of water cant be used
    for drinking, irrigation, or industry
    because its mostly all salt water.
      Some of the deadliest and most
    famous civilian maritime disasters:
   Dec. 20, 1987 - In the world's worst peacetime shipping disaster, 4,340
    drown when the ferry Dona Paz collides with the tanker MT Victor in the
   Aug. 31, 1986 - Soviet passenger ship Admiral Nakhimov collides with a
    merchant vessel in the Black Sea, sinking both ships and killing up to 448
   Jan. 27, 1981 - 580 killed when Indonesian passenger ship Tamponas II
    catches fire and sinks in Java sea.
   July 25, 1956 - Two passenger liners, the Andrea Doria and the
    Stockholm, collide off Massachusetts, sinking the Andrea Doria and killing
    46 of its 1,706 passengers and crew.
   May 7, 1915 - The British ocean liner Lusitania is torpedoed and sunk by a
    German U-Boat while crossing the Atlantic Ocean, killing 1,195 people.
   May 29, 1914 - A Canadian Pacific steamship, the Empress of Ireland,
    collides with a Norwegian freighter near Quebec, sinking in 14 minutes
    and killing 1,012 people.
   April 12, 1912 - The Titanic - the world's largest passenger steamship at
    the time- strikes an iceberg in the Atlantic and sinks on its maiden
    voyage, killing at least 1,496 people.
   June 15, 1904 - The steamship General Slocum catches fire in New York's
    East River, killing more than 1,000 people.
   April 27, 1865 - The steamboat Sultana sinks after its steam drum
    explodes on the Mississippi River, killing at least 1,700 people.
                  Currents- QUIZ
   1. What is the location of these currents? Identify using the
    ocean they exist in, and N, S, E, W of the continent/state
    they are nearest, and the direction they are moving. (ex: S
    off the Coast of Florida- moving west).
   - a) Gulfstream b) South Indian c) Antarctic subpolar d)
    Antarctic circumpolar
   2. The current east of Japan is the ___________.
   3. The current running south, off the coast of Madagascar is
    the _____________.
   4. The Peru current runs S to N, up the South American
    coast and originates from what other current?
   5. Which current, off the E coast of the United States,
    greatly effects our weather patterns? ____________

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