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Deep-ocean trenches are the deepest parts of the ocean.  a) What are deep-ocean trenches?  How are they related to plate tectonics?  Be sure to explain in your own words. b) Name a deep-ocean trench and describe where it is located. Extra credit:  Why are trenches always deeper than the seafloor next to them?    Do not rely just on Figure 4-11 for this question.  Also see Figure 4-15.

Ocean in the climate system: a) Why is the ocean a dominant factor in the Earth’s climate system?  Give 4 global-scale reasons and for each one explain how the ocean affects climate. b) Which do you think is the most important, and why?

Longshore currents: a) Under what conditions do longshore currents form? b) Describe 2 ways in which rip currents are different from longshore currents.  Do not simply give definitions of each one.  Instead, explain how they are different.Rip currents are described in the second reading assignment: Segar page or Mpora page.

To a remarkable extent, advancement of ocean science depends on advancement of technology.  Choose two (2) technologies that have played an important part in oceanography.  Several are described in the chapter, or you may choose others that you know about.  Do not use ROVs, AUVs, HOVs, echo sounding, or satellite altimetry.  Those technologies were discussed in the previous two questions. For each of your 2 technologies, describe: how the technology works what major advances it led to  

Describe 3 significant problems that scientists would encounter in studying ocean biology if they used only sampling with nets.  Your answers should describe scientific problems, not logistical problems. A scientific problem is one that affects the information or sample characteristics that you collect with the nets.  These are discussed in the chapter.  A logistical problem is one that makes the use of nets physically difficult; for example, very heavy nets would be difficult to handle.  Do not include such answers.

Marine Food Web:  a)  In reference to the oceans, what is the difference between primary production and secondary production?  (Note: This question is about the process of production, not who the producers are.) b)  Use the concepts of trophic level and food chain inefficiency to describe how food energy flows through a marine food chain or food web.  Be sure to describe this in your own words, and use both terms in your answer.   (Note:  “trophic level” does not refer to types of organisms.)

This exam will cover chapters 11-13. You will have 2 hours to complete the exam.You may use the following on the exam:BLANK scratch paper, 3X5 notecard (no examples), calculator (no cell phones), and a periodic tableConstants will be given unless otherwise noted.For the fill in the blank ALWAYS INCLUDE UNITS when needed.

Consider the following reaction:6CO2 (g) + 6H2O (l) ↔ C6H12O6 (s) + 6O2 (g)    Initially a 500 mL container had only 0.25 mol of CO2 gas. After the reaction is allowed to reach equilibrium only 0.08 mol CO2 remain. What is the equilibrium constant for this equation?

Albedo:  The global average albedo of the ocean is about 8%.  (This is stated in Chapter 04 right before Table 4.2.) a) How does the average albedo of the oceans compare with that of sea ice? b) Does the ocean have a higher or lower albedo than land surfaces?  Use the global average albedo for the ocean. c) Global warming will affect ice surfaces on both ocean and land.  How will this change Earth’s surface albedo?  d) How will that change in Earth’s albedo (in part c) affect climate?  Be sure to explain your answer.

Latent heat:  The topic of latent heat is discussed in Chapter 3 section 3.3.1 Heat Properties and in Chapter 4 section 4.4.1 Latent Heating.  Phase changes include the processes of evaporation, condensation, melting, freezing, sublimation, and deposition of water.  Phase changes do not involve temperature changes.  The scientific term for this kind of heat transfer is “latent heat”.  See Figure 3.3B, shown below with its figure caption.  That figure applies whether the temperature is increasing OR decreasing.  A VIDEO explaining this figure is posted on the Ch04 Reading and Video Assignments page.  Don’t worry about the brief equations.  The rest of the video is very good. a)  Using the concept of latent heat, explain why changes in the phase of water (between gas, liquid, and solid) also transfer heat energy within the Earth systems.  b)  Describe how this process could transfer latent heat from the ocean to the atmosphere.  c)  At what point in the process would the atmosphere become warmer?   (Figure 3.3B) Water’s latent heat of fusion (melting) is the amount of heat that must be added to convert ice to water at the freezing (melting) point temperature. Water’s latent heat of vaporization is the amount of heat that must be added to water to convert water to water vapor at boiling point temperature. Both of these are high to provide energy to overcome the hydrogen bond attraction. As latent heat is added to change the phase, there is no change in temperature. In the reverse processes, the same amounts of latent heat that were added are released when water vapor condenses and when water freezes. The specific heat of water is the amount of heat required to raise the temperature of 1 g of liquid water by 1°C and is measured in calories per gram-degree Celsius (Joules per gram-degree Celsius). The same amount of heat is released as water cools.