GEOL 1080

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					                                    PRELIMINARY MIDTERM III STUDY GUIDE
                             GEOL 1080 • INTRODUCTION TO OCEANOGRAPHY • FALL 2010
                                                            Utah Valley University
READ THIS FIRST: this outline is not meant to be fully comprehensive. This lists all the major topics we discussed in class, but it
    does not completely cover everything involved with every topic, so use this as a guide to your notes, and to what to look at
    in the text.
WHAT THE EXAM WILL COVER: The exams will focus on seawater and air-sea interactions (Ch.’s 5 and 6).
WHEN THE EXAM WILL TAKE PLACE: The exam will be available in the CTC from Monday 11/22 through Wednesday 11/24
    Wednesday will be a late day and will cost $3. You must take the exam at the CTC.
INSURANCE: Insurance is 4 pm Tuesday 11/23 in the College of Science main office or delivered to me before class in PS 102.
    Make yourself a photocopy of your insurance work and be sure to follow the directions to ensure you get full credit.

1. Seawater!
    a. Atoms are the smallest particles that retain the characteristics of specific elements. They consist of:
         i. Nucleus:
               1) protons (+) charge, mass (of ‘1’)
               2) Neutrons, no charge, mass (of ‘1’).
         ii. Electrons: (-) charge (equal but opposite to proton), almost no mass. Electrons orbit around the nucleus in shells. It
               is energetically favored for atoms to have full outer shells.
         iii. In its neutral state an atom has the same number of electrons as protons and thus no net charge. If an atom obtains
               an extra electron, the atom has net negative charge; if and atom gives up an electron, it will have a net positive
               charge. Atoms not in base state are called ions
         iv. bonding: atomic bonding results from interactions between electrons of neighboring atoms. The electrons interact
               because it is energetically favored for atoms to have full outer shells. Consequently, atoms can give away or take
               electrons and then bond because of their resulting net charges (ionic bonding), or because atoms share electron(s)
               to produce a single full shell that surrounds both atoms (covalent bonding).
    b. Elements
         i. Atoms naturally come in 92 main varieties. These are the naturally occurring elements. The difference between
               atoms of different elements is the number of protons in the nucleus. The number of electrons or neutrons in
               atoms of the same element can vary. E.g., all Carbon atoms have 6 protons, but some have 6 neutrons, a few have
               7, and a very few have 8 (these are the three isotopes of carbon). Similarly, the number of electrons varies, and in
               fact the same atom can give up and take electrons easily and repeatedly. The number of protons is the basic control
               on the chemical and physical behavior of an atom.
    c. The water molecule
         i. What is the water molecule?
               1) H2O
               2) The smallest amount of water you can have (definition of a molecule).
               3) Two hydrogen atoms bonded to an oxygen atom by sharing of electrons.
         ii. Geometry and bonding of the water molecule.
               1) Both H atoms are on the same side of the O atom! – 105o angle between the H atoms.
               2) Covalent bond between H and O.
                     a) Covalent bonds result from sharing of electrons; each H atom shares its electron with O.
                     b) Covalent bonds are a very strong type of chemical bond.
                         i) Ionic bonds (see above)
         iii. Polarity of the water molecule. The end of the water molecule on which the H atoms reside has a net (+) charge;
               the O end has a net (–) charge. This is because the electrons that are shared between each H and O atom are not
               evenly shared – they spend more time around the O atom than the H atom. The polarity of the water molecule
               gives water its special qualities and is very important.
         iv. Interactions between water molecules - they are attracted to each other because they’re dipolar
               1) The connection between water molecules is called a hydrogen bond. Do not confuse this with the covalent
                     bond between H and O within and individual water molecule.
               2) These hydrogen bonds are much weaker than the covalent bonds that hold individual water molecules together.
               3) This attraction between water molecules creates surface tension. Causes drops to form, water to bead-up on
                     some surfaces; lets water stick-up a bit above the top of a glass.
               4) This attraction gives water the remarkable properties that are described below.
         v. Water as a solvent
               1) Why is water such a good solvent? (the ‘Universal Solvent’).
                     a) Many materials are ionically bonded, and even many of those that are covalently bonded show some
                         polarity.
GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                     page 1 of 8
                b) Water is strongly polar, can latch onto edges of polar solids, and breaks them apart
                c) Dissolved substances become hydrated, and are held ‘in solution’ in the water.
                d) Water can dissolve more of more materials than any known solvent; hence its name ‘The Universal
                      Solvent.’
                e) 3.5% of ocean mass is dissolved substances = 50 quadrillion tons = 50x1015 tons = 100x1018 pounds
                f) But why doesn’t water dissolve oil better? Oil is highly nonpolar. To a certain extent, organisms evolved
                      that way to prevent us from getting dissolved by water.
       vi. Water’s (Remarkable) Thermal Properties
            1) Water is remarkable in that it stays solid and liquid to high temperatures (considering its low molecular mass),
                and in that can hold very large amounts of heat - in two ways. Its ability to hold heat energy greatly influences
                ocean circulation, weather & climate, and daily and yearly ocean temperature changes – hence it influences life
                greatly.
            2) First some background ideas and terminology: (know these)
                a) Heat
                b) Temperature .
                c) calorie
                d) States of matter – solid, liquid, gas (at least the ones we need to know here)
 State     Bonding           Distance between             Motion of            Temperature
           between           Molecules                    molecules            (relative to
           molecules                                                           other states)
 Solid     Strong            Close, in contact            Vibration, but       Low
                                                          no real
                                                          displacements
                                                          accumulate
                                                          between atoms
                                                          or molecules
 Liquid       Weak                In contact                     Vibration and      Medium
              To                                                 moderate lateral
              None                                               displacements
                                                                 between atoms
 2. Gas       3. None             4. Very far apart              5. Rapid lateral   6. High
                                                                     motion and
                                                                     vibration

               1) Freezing and Boiling Points of water
                   a) Definitions of melting/freezing and boiling/condensation
                       i) When enough heat energy is added to a solid, it melts. The temperature at which this happens is called
                             the melting point or melting temperature.
                       ii) When enough heat energy is removed from a liquid, it will freeze. The temperature at which this
                             happens is called the freezing point or freezing temperature. The freezing point always exactly
                             equals the melting point. This temperature is 0oC (32oF) for water at sealevel. [oF = oC x 9/5 + 32].
                       iii) Similarly, when enough heat energy is added to a liquid, it boils. The temperature at which this
                             happens is called the boiling point or boiling temperature.
                       iv) When enough heat energy is removed from a gas, it will condense. The temperature at which this
                             happens is called the condensation point or condensation temperature. The condensation point
                             always exactly equals the boiling point. This temperature is 100oC (212oF) for water at sealevel.
                   b) Water has very unusually high melting and boiling points for its molecular weight. This is because it is
                       (di)polar and forms hydrogen bonds that tend to keep it as a solid or liquid. If it wasn’t polar, it would
                       freeze at –90oC [-130oF] and boil at –68oC [-90oF]. Note that not only are these temps lower, but that the
                       range over which it would be liquid is much less. If water wasn’t polar, all water on Earth would be
                       gaseous and the skiing would suck!
               2) Water’s Heat Capacity
                   a) The heat capacity of a substance is the amount of heat that is required to raise the temperature of 1 gram of
                       a substance by 1oC. [1 g is ~1/28 oz; 1oC = 1.8oF].
                   b) So a substance with a large heat capacity can absorb large amounts of heat without its temperature
                       changing much. A substance that gets hot readily when heat is added has a low heat capacity.
                   c) Q- Name substances with high and low heat capacities. A- Think of the microwave (e.g., butter vs. water).
                       Most all oils and metals have low heat capacities.


GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                      page 2 of 8
                   d) Water has a heat capacity of 1 calorie; nearly all other substances have lower heat capacities. This is
                         because hydrogen bonds must be broken to get the water molecules moving and that takes lots of heat
                         energy. Remember, temperature directly measures the movement of molecules/atoms in a substance.
              3) Water’s Latent Heat of Melting and vaporization.
                   a) It takes lots of energy to break hydrogen bonds and transform water from solid to liquid or liquid to gas.
                         These are the latent heats of melting and vaporization.
                   b) The amounts of energy required are 80 calories for melting (to melt 1 gr of ice; more technically, to
                         transform 1gr of ice to water at 0oC), and 540 calories for vaporization (to boil 1 gr of water; more
                         technically, to transform 1gr of water to vapor at 100oC)
                   c) Called latent because it is hidden. Adding heat, but temperature is not being raised. Heat energy is going
                         into the change in state of the water (from liquid to gas or from solid to liquid).
                   d) The energy (latent heat energy, that is) is available to be given back: during condensation and freezing,
                         identical amounts of heat energy are released.
                   e) Evaporation vs. Vaporization. The transformation of a substance, such as water, from a liquid to a gas at a
                         temperature less than its boiling point is call evaporation.
                         i) Latent heat of evaporation. More energy is required to evaporate water than to vaporize it (because the
                               water is cooler). For example, 585 calories of heat energy is required to evaporate 1 gr of water at
                               20oC [68oF]. The amount of latent heat required for evaporation depends upon the temperature at
                               which the evaporation occurs.
                         ii) An important consequence of the latent heat required for evaporation is the strong cooling effect on the
                               remaining water when water evaporates. (The latent heat of evaporation is provided by a decrease in
                               the temperature of the water that remains as a liquid).
                         iii) If water is evaporated in one place and then condenses elsewhere, a large amount of heat is
                               transported.
         ii. Water Density (liquid - solid)
              1) With cooling, liquid water becomes slightly more dense from 100oC down to 4oC (about 212oF to 39oF). So it
                   contracts and takes up less volume.
              2) Between 4oC and 0oC, waters density decreases slightly. It expands slightly. So at 4oC, water attains its
                   maximum density.
              3) Freezing causes water to become significantly less dense – the change is about 9%. (note that freezing occurs at
                   less than 0oC for saline water, i.e., seawater).
     d. Salinity
         4) Refers to total amount of dissolved solid material in the water. Solid material only; does not refer to gases, some of
              which are dissolved into seawater.
         5) Refers to all water – really is no such thing as natural pure water.
         6) Seawater averages 3.5% salinity. 96.5% pure.
              a) Commonly measured in parts per thousand instead of percent, which is parts per hundred. So salinity of
                   seawater commonly reported as 35‰ instead of 3.5%.
              b) Varies from 33 to 38‰ in open ocean.
              c) 6 elements account for 99% of the tds. Know these 6 elements and be able to list them in order of relative
                   abundance (don’t need to know each one’s exact concentration).

               d) Minor constituents; know that the abundances of these are measured in parts per million and even parts per
                   billion, and know the names of the important abundant ones. Know what parts per million means.
               e) Principle of constant proportions – total salinity varies, but ratio of the major dissolved constituents is virtually
                      Constituent                                    Concentration         Ratio of constituent to total salts
                                                                                                          (‰)
                      Cl- (Chloride)                                        19.3                            55
                      Na+ (Sodium)                                          10.7                           30.6
                      SO42- (Sulfate)                                        2.7                            7.7
                      Mg2+ (Magnesium)                                       1.3                            3.7
                      Ca2+ (Calcium)                                        0.41                            1.1
                      K+ (Potassium)                                        0.38                            1.1
                      Total                                                34.79                           99.3
                  identical everywhere. This implies that the oceans are well mixed and that variations in salinity result from
                  addition or removal of pure water. Know this idea.
          7) Origin of salinity


GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                        page 3 of 8
                a) Water on land dissolves rocks to limited extent, carries material to oceans. Water is evaporated from oceans,
                     leaves dissolved solids behind.
                b) Some comes from waters that circulate at mid-ocean ridges
          8) Variations in salinity
                a) Fresh water - Decent tap water contains < 0.8‰, good tap water is < 0.6‰ and good bottled water is < 0.3‰.
                b) Great Salt Lake is about 280‰ – about 9 times more saline than typical seawater.
                c) Varies between 33 and 38‰ in open ocean
                     i) As low as 10‰ and as high as 42‰ in some area. Influx of ‘fresh’ river water, removal of water by
                           evaporation causes the variations (see Principle of Constant Proportions).
                     ii) High salinity at low latitudes (high evap.); low salinity where lots of river run-off (Alaska).
                     iii) In general, salinity is a balance between addition and removal of dissolved solids, and addition and
                           removal of pure water. Very constant over time – only minor variations in total salinity.
                d) Variations with depth
                     i) Below about 1 km depth, salinity is very consistent worldwide: evaporation and runoff don’t effect deep
                           ocean.
                     ii) But at high latitudes relatively low salinity at surface, whereas at low latitudes relatively high salinity at
                           surface.
                     iii) Depth range over which there is gradient from surface conditions to stable depth conditions is called the
                           halocline.
    iii. Seawater density
          1) Depends upon temperature and salinity; temperature is by far most important.
          2) Understand and be able to sketch the figures on page 155 of text.
          3) Three distinct zones with depth at low to mid - latitudes, where surface water is warmer and lower density than
                deeper waters.
                a) Mixed surface layer
                b) Upper water zone. Not mixed and does not mix with the deep water below
                c) Deep water below 1000m – fairly homogenous in temperature and salinity, but does not mix with water above.
    iv. Transmission of light through seawater
          1) Know what electromagnetic radiation is.
          2) Light does not penetrate very deep – 45% makes it to 1m; 16% makes it to 10m; only 1% makes it to 100m. If you
                want to photosynthesize, live near the surface!
          3) Blue light penetrates best; hence water free of particulate matter and plankton looks blue.
          4) Particulate matter and plankton scatter yellow-green light, making water look more that color where they are
                abundant.
    b. Transmission of sound through seawater
          i. More efficient (less attenuation) than in air
          ii. Faster than in air
          iii. Organisms use it
          iv. SOFAR channel
2. Air – Sea Interactions (Chapter 6)
    a. Energy from the Sun
          i. Basic driving force behind air and ocean circulation
                1) At high latitudes there is less heating (regardless of time of year).
                     a) At high latitudes there is less incident radiation per m2 area
                     b) At high latitudes there is more reflection on average
                2) Amount of solar heating at any given spot varies with the seasons
                3) More heat reaches surface at tropical latitudes than escapes back into space and vice versa in the arctic and
                     Antarctic. Tropics do not continually warm (and high latitudes don’t continually get colder) because the
                     excess heat from the tropics is transferred to polar regions by atmospheric and oceanic circulation.
    b. The Atmosphere
          i. Some basics
                1) Composition: mostly N2 (78%) along with some O2 (21%).
                2) Divided into troposphere, stratosphere and mesosphere. All weather happens in troposphere – that’s what we
                     are concerned with.
                3) In troposphere, temperature decreases with elevation.
                4) Warm air is less dense and rises; cool air is more dense and sinks
                5) Convection cell concept
                6) Air flows horizontally from regions of high pressure to regions of low pressure.
                7) Rising air leaves low pressure at surface; sinking air creates high pressure at surface
          ii. Global Model fo Air movement on the Earth – KNOW THIS.
GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                          page 4 of 8
                1) Hypothetical nonspinning Earth: Two large convection cells that redistribute heat that is input onto Earth by Sun
                2) But Earth spins, which causes The Coriolis Effect
                    a) Because the Earth is spinning, objects traveling across Earth appear to curve to the right in the Northern
                         Hemisphere and to the left in the Southern Hemisphere.
                    b) Effect is greatest at poles and least at Equator (goes to zero actually).
                3) Combination of effects described in nonspinning Earth example and Coriolis effect create circulation cells and
                    wind belts.
                    a) Air cannot simply move from poles to equator – Coriolis effect causes it to curve across Earth’s surface. See
                         figure 6-10.
                    b) Three convection/circulation cells per hemisphere
                    c) There is a surface wind belt associated with each cell –
                         i) NE and SE Trade winds
                         ii) Prevailing Westerlies (N & S)
                         iii) Polar Easterlies (N & S)
                         iv) Doldrums, Horse Latitudes and Polar fronts at cells boundaries. Doldrums and polar fronts are
                               sites of enhanced precipitation. Doldrums referred to as ‘Intertropical Convergence Zone’ or
                               ITCZ.
                    d) Be able to draw and label the global air circulation model, complete with convection cells and major
                         wind and climate belts.
          iii. Relatively localized air movements: surface high and low pressure centers, land and sea breezes
                1) Surface low pressure centers – air is rising, flowing inwards towards center at and near ground surface. Coriolis
                    effect deflects motion; in N. Hemisphere, counter-clockwise ‘cyclonic’ flow develops. Be able to draw this.
                2) Surface high pressure centers – air is sinking, flowing outwards from center at and near ground surface. Coriolis
                    effect deflects motion; in N. Hemisphere, clockwise ‘anticyclonic’ flow. Be able to draw this.
          iv. Sea (and land) breezes.
                1) Heating of land during day causes air to rise, sucks air inland off the water – this is the ‘sea breeze’ that often
                    kicks in late on warm days.
                2) Cooling of land during night causes air to sink, flow out over ocean. This is a night time, early morning ‘land
                    breeze.’
          v. Storms
                1) Mid-latitude storms –
                    a) Broadly speaking, caused by collisions of cold and warm masses of air along the polar front. When air
                         masses collide, warm air rises, which causes it to cool, water condenses, it rains/snows.
                    b) Cold front forms if the mass of cold air is moving more rapidly than the warm air mass, and the cold air
                         mass forces its way underneath warm air.
                    c) Warm front forms if the mass of warm air is moving most rapidly and forces its way over the cold air.
                2) Tropical Cyclones –
                    a) Hurricanes in Americas, typhoons in W. Pacific, and cyclones in Indian ocean
                    b) Low pressure centers that initiate in along the equator, migrate north or south
                    c) Take advantage of warm ocean and warm moist air, which provides the energy; Coriolis effect, which
                         causes the system to spin
                    d) Move towards the west on the trade winds, and to the north or south away from equator (depending on
                         hemisphere).
                    e) Transport large amounts of water vapor, and thus energy northwards away from equator
                    f) Air moves to center, spiral upwards. Rising air cools, water condenses, precipitates. Warm water provides
                         energy to generate lift.
                    g) Damage:
                         i) Winds
                         ii) Storm surge – the big killer
                               (1) As storm approaches coast, winds push water onto land
                               (2) Extreme low pressures allow water level to be higher (atmosphere is pushing down with more
                                    pressure elsewhere, so water level rises under the storm)
                               (3) Surges can be as high as 12 m; a couple to a few meters is common.
                               (4) Example: Galveston, TX, 9/8/1900. 6m surge, 6000 deaths, most by drowning. Almost no
                                    warning.
                               (5) Andrew, 8/1992, $20 billion damage; 160 mph winds; ‘only’ 54 deaths.
          vi. Greenhouse Effect
                1) Sun heats the Earth by radiating visible light energy to Earth. Earth sends energy to space as infrared radiation,
                    which keeps Earth from progressively heating over time.

GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                       page 5 of 8
               2) Gasses in the atmosphere inhibit escape of infrared radiation, just as glass windows of a greenhouse do. Glass &
                   atmos. let light in easily – interior gets heated. However, glass & atmos inhibit escape of infrared radiation
                   (and heat). Car and greenhouse get warm as a result. However, the amount infrared radiation produced
                   increases with temperature, and eventually the car, greenhouse, or earth is hot enough that it produces enough
                   infrared so that the fraction that escapes through the glass or atmosphere is equal in energy to the amount of
                   incident solar radiation. In this way the temperature in the greenhouse and on Earth remains nearly constant.
               3) The gasses in the atmosphere that do this are CO2, H2O, CH4; these are called the greenhouse gasses.
               4) Without these gasses and this effect, Earth surface would average about –20oC instead of 13oC. Venus’ surface
                   temperature is about 470oC due to large amounts of CO2 in its atmosphere.
               5) Climate Change is the idea that the climate is changing, which it is. Global Warming is the related and more
                   specific idea that the climate is getting warmer, which it is.
               6) An important question is why is the climate is warming? If amount of greenhouse gasses increases,
                   greenhouse effect increases, earth warms. By burning fossil fuels, humans have produced increased the
                   amount of CO2 in the atmosphere by over 30%. Nearly all data indicates that these human-produced
                   greenhouse gasses are the primary cause of current global warming, although natural climate change may also
                   be playing a role. For the past 1 million years, ice ages have occurred on a 100,000 year cycle and for 1.5
                   million years before that, ice ages occurred on a 41,000 year cycle. CO2 concentration in the atmosphere has
                   varied on exactly the same cycle, with larger concentrations of CO2 having occurred when the Earth’s climate
                   was warmer (“interglacials”). Prior to the industrial revolution, CO2 levels were the same as during past
                   interglacials. However, during the past ~150 years, CO2 levels have increased by ~30% due to burning of
                   fossil fuels by humans; at the same time global temperatures have risen 1 to 2oC which is much more than they
                   rose in the previous centuries; this is some of the powerful evidence for the human contribution to global
                   warming.
               7) Ocean role in CO2 concentrations: oceans absorb CO2 by the reaction CO2 + H2O => H+ + HCO3-. This acidifies
                   the oceans, and calcite is dissolved (CaCO3 + H+ => Ca2+ + HCO3-)
               8) Our useage of fossil fuels and production of greenhouse gasses?
                   a) 7 x 109 tons per year, net, put into atmosphere by humans.
                   b) Burning rain forests at rate of about 1 acre per second.
                   c) How much CO2 is produced when you burn gasoline? Gasoline is (idealized) octane, C8H18. Burning of
                        octane in an internal combustion engine (i.e., in a car), follows the reaction: C8H18 + 12½ O2 => 8(CO2) +
                        9(H2O) [gasoline + oxygen gas combined by burning forms carbon dioxide gas and water , and in the
                        process a lot of heat is released]. Thus, 8 CO2 molecules are produced for each octane molecule that is
                        burned. If you compare the weight of CO2 and octane, you find that burning 1 lb of gasoline produces
                        3.1 lbs of CO2. A gallon of gas weighs about 6 pounds.
                   d) Tremendous revenues and profits are generated in the fossil fuel extraction industry. ExxonMobil had net
                        profits of approximately $40 billion the past two years and holds the record among all privately held
                        companies for the largest net profit in a quarter (3 months) of approximately 11 billion dollars.
               9) Fossil fuel resources
                   a) Coal – cheap, still fairly plentiful. Creates more pollution than oil or natural gas; pollutants include CO2,
                        NOx, Sulfur (acid rain), mercury. Produces more CO2 than oil or natural gas. Much electricity in the U.S.
                        is produced in coal-fired power plants; ~97% of electricity in Utah comes from coal.
                   b) Petroleum (oil). Has pollution and supply issues. Burning 1 lb of gasoline produces about 3.1 lbs of CO2,
                        and a gallon of gas weighs about 6 lbs. Supply issue revolves around production rates more than total
                        reserves, and basic economic theory of natural resource production indicates that we are near the
                        maximum production rates that we will ever have.
                        i) Formation requires (1) Source rock, (2) thermal maturation and migration, (3), reservoir rock, (4) seal
                             rock, and (5) a trap. Be sure to read the handout.
                        ii) Largest reserves are in the Middle East (1 to 2 trillion barrels probable). There are large reserves in
                             North America and former Soviet Union countries.
                        iii) U.S. consumes about 7 billion barrels annually; global consumption is about 28 billion barrels.
                   c) Natural Gas. Very little toxic pollution, but produces large amounts of CO2 (although somewhat less CO2
                        than petroleum or coal. Many people strongly prefer its use over coal in electrical power plants.
                   d) Biofuels. Ethanol (alcohol) and biodiesel are the main types. Currently in the U.S., it takes approximately 1
                        gallon of petroleum to produce 1 gallon of ethanol, so CO2 emissions are not reduced by ethanol use.
                        However, mixing small amounts of ethanol with gasoline can improve combustion of the gas in cars which
                        can significantly reduce pollution and this is done in many parts of the U.S. Ethanol is successfully
                        produced in Brazil (but with some drawbacks). Ethanol-powered motors produce more horsepower than
                        those fueled by gasoline.
                   e) Wind. Clean, has potential to provide a significant proportion of electrical power in the U.S. if we invest in
                        it and are willing to establish numerous large ‘windmill farms.’
GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                      page 6 of 8
                  f) Solar. Expensive initial investment is a barrier to its widespread use, although it has become cost effective
                       in a significant number of applications.
                  g) Nuclear. Potential for devastating accidents and disposal of highly radioactive waste (that has potential to
                       be used in bombs) has made it prohibitively expensive to build additional plants in the U.S., although it
                       currently supplies a significant proportion of our electricity nationally. New technology and/or changes in
                       political will may lead to a comeback.
                  h) Hydrogen and electric cars. The electricity or hydrogen must be produced at a power plant utilizing coal,
                       natural gas, nuclear, wind, or solar energy. However, electric cars do offer an efficiency advantage
                       (meaning good mileage per lb of CO2 produced when electricity is generated using natural gas or even
                       coal), and hydrogen cars may as well when more fully developed, and solar or wind power could be used.
                       Also, there can be advantages to producing the power at plants located outside major population centers.
3. Calculations. There will be more than one question that involves these types of calculations on the exam. You should
    be able to do the following:
    a. Convert units, for example convert km to m. Do the conversion before you do any other calculations. There are 100 m in
        a kilometer (1000 m = 1 km) (but it IS NOT TRUE that 1000 m2 = 1 km2 so don’t try to do that!!!!!).
    b. Be able to manipulate and solve problems using the relationship d= r x t
    c. Radius and circumference of circles and spheres C = 2 x π x r
Study Questions
If you want to turn these in, please be sure to answer them on separate sheets of paper and staple everything together! Note that if you
score below C- on the exam you can receive points equivalent to a C- by doing these questions AND the suggested problems from the back of
the appropriate chapters AND turning them all in before the end of the testing period. The suggested chapter problems are listed on the
syllabus (which you received in class and is available on the course website).
1.    How do the atoms of different elements differ from each other?
2.    Can the number of electrons in a Carbon atom vary?
3.    Do all Carbon atoms have the same number of neutrons?
4.    How do covalent bonds differ from ionic bonds?
5.    What type of bond exists between the hydrogen atoms and oxygen atom in a water molecule? Is this a strong bond?
6.    Draw a water molecule; be sure to get the positions of each atom correctly and include the charge distribution on the
      molecule.
7.    Are water molecules attracted to each other? Why or why not?
8.    What kinds of substances is water particularly good at dissolving (think in terms of electric charges and types of bonds)?
      Why?
9.    Sketch a sodium chloride crystal and some water molecules and explain how water dissolves it.
10.   Describe freezing, melting, condensation and boiling, and give the points (temperature) of each for water.
11.   What is the heat capacity of a substance (i.e., describe the concept)? What is the heat capacity of water (i.e., a number –
      with units!)?
12.   Relative to other substances, does water have a high or low heat capacity? Why?
13.   Describe a way that water’s heat capacity impacts surface temperatures on Earth.
14.   What is latent heat? Why is it called latent? What is the latent heat of vaporization of water (give a number and units)?
15.   What is the difference between the latent heat of vaporization and latent heat of condensation in water (there is a
      distinction)?
16.   Explain how ice keeps a beverage cold, using your knowledge of heat capacity and latent heat.
17.   What is the difference between boiling and evaporation?
18.   Is water vapor in your kitchen visible?
19.   What is the density of a substance?
20.   Sketch (neatly) a graph of pure water’s density vs. temperature. At what temperature does water attain its maximum
      density?
21.   How might the behavior of water differ if the hydrogen atoms were attached on directly opposite sides of the oxygen atom
      (i.e., all three atoms were in a line)? [There should be several parts to this answer – water’s solvent properties, heat
      capacity, latent heats, density, melting and vaporization points].
22.   Explain what is meant by the salinity of seawater.
23.   What is the average salinity of seawater? Be sure to give the salinity in the standard units, using standard notation.
24.   What is the origin of most of the salinity of seawater?
25.   List, in order of decreasing concentration, the 6 most abundant constituents of the salinity of seawater.
26.   What is the typical range in salinity of seawater in the open ocean?
27.   Explain the principle of constant proportions. Be sure that you understand this concept.

GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                          page 7 of 8
28. In some parts of the oceans, the salinity is less than average; name 3 causes of this decreased salinity and explain what
     factor all 3 causes have in common.
29. In what parts of the oceans (where on Earth) is salinity typically less than the average value?
30. In some parts of the oceans, the salinity is greater than average; name a cause of this increased salinity.
31. In what parts of the oceans (where on Earth) is salinity typically greater than the average value?
32. What are the typical concentrations of the minor constituents of seawater salinity (i.e., in what units are they usually
     reported)?
33. Graph typical ocean water temperature vs. depth for both high and low latitudes. Label all the key elements of the graph.
34. Graph typical ocean water salinity vs. depth for both high and low latitudes. Label all the key elements of the graph.
35. Graph typical ocean water density vs. depth for both high and low latitudes. Label all the key elements of the graph,
     including the three horizons of low latitude water.
36. What is wave refraction?
37. What is the SOFAR channel, and how does refraction of sound waves create it?
38. What color of light penetrates seawater best (most effectively)?
39. What percentage of the energy of light that strikes the ocean surface penetrates to 10 m depth, on average?
40. What is the primary source of energy that drives atmospheric and oceanic circulation?
41. If neither the oceans nor the atmosphere circulated globally, how would the typical daily high temperature in Ecuador
     change? How would the typical daily high temperature in Antarctica change?
42. The Sun adds heat energy to the Earth each day. Why doesn’t the Earth get much hotter with each passing day, as a result
     (ignoring global warming)?
43. What are the three most abundant gases in the atmosphere, and what percentage of the atmosphere does each constitute?
44. What is the troposphere? How does temperature vary with height in the troposphere?
45. How does the Sun cause air to rise, and indirectly, to sink?
46. What creates regions of high pressure at the Earth’s surface? What creates regions of low pressure at the Earth’s surface?
47. Differences in what physical property of air between places on the Earth’s surface causes horizontal movements of air
     (winds)?
48. Combine your answers to questions 6 through 8 to explain how the Sun causes horizontal winds on the Earth’s surface.
49. Draw the model of the major air circulation patterns on Earth. Include the major convection cells, wind belts, regions of
     high and low surface pressure, and regions of enhanced and relatively little precipitation. Be able to draw this model from
     memory.
50. Show how cyclonic flow develops around a low pressure area in the northern hemisphere by drawing and labeling an
     illustration.
51. Show how anti -cyclonic flow develops around a high pressure area in the northern hemisphere by drawing and labeling an
     illustration.
52. Explain what a sea breeze is, and how they form. Use a sketch to aid your explanation.
53. Why is the duration of precipitation at a particular location from a passing cold front usually shorter than from a warm
     front? Use labeled sketches of both a warm and cold front to illustrate your explanation. Be sure you understand both
     types of fronts.
54. Sketch a mid-latitude cyclone with a warm front and a cold front.
55. How do tropical cyclones differ from midlatitude storms?
56. How do tropical cyclones cause sea level to rise?
57. List the factors that favor formation of tropical cyclones in the tropics.
58. What is the most deadly aspect of tropical cyclones?
59. How are hurricanes ranked in the U.S.?
60. What is the difference between a typhoon and a hurricane?
61. Using a sketch and sentences, explain how storm surge along a coast varies in relation to the position of a hurricane eye.
62. Explain the greenhouse effect, including the major greenhouse gases in the atmosphere.
63. How would Earth’s climate be different if there weren’t a greenhouse effect?
64. How long will it take a 25 mph wind to travel 1000 miles?
65. What is the circumference of the Earth?




GEOL 1080, Introduction to Oceanography, Midterm 3 Study Guide, Professor Bunds                   page 8 of 8

				
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