UNIVERSITY OF EAST ANGLIA
School of Environmental Sciences
Main Series Undergraduate Examination 2012-2013
ATMOSPHERE and OCEAN
ENV-1A56
Candidate Number ……………………………….
Time allowed: 1 hour.
Answer ALL 25 questions.
All questions are worth 4% each.
ANSWER ALL QUESTIONS ON THE EXAM PAPER IN THE SPACES
PROVIDED.
Provided:

ENV Data Book
Scientific calculators are permitted.
Notes are not permitted in this examination.
Do not turn over until you are told to do so by the Invigilator.
ENV-1A56
Module Contact: Dr Parv Suntharalingam, ENV
Copyright of the University of East Anglia
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1. a) State the Stefan-Boltzmann equation for a perfect black-body radiation
emitter?
[2%]
b) Assuming the Sun is a perfect black body emitter, what is its rate of energy
emission?
[2%]
You can take the surface temperature of the Sun as 6000K, and the value of
the Stefan-Boltzmann constant as 5.673 x 10-8 J m-2 s-1 K-4.
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2. Why do we have seasons?
In your answer, refer to the relevant aspects of the Earth’s orbital
characteristics. Keep your explanation succinct and use diagrams if
necessary.
[4%]
3. a) Explain how the presence of greenhouse gases in the Earth’s
atmosphere affects surface temperature. (Keep your answer short; 2-3
sentences)
[2%]
b) Name two atmospheric chemical constituents that are greenhouse gases.
[2%]
PLEASE TURN OVER
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4. a) On the following diagram, which shows the variation of atmospheric
temperature with altitude, mark the altitude ranges for the troposphere and
stratosphere.
[1%] + [1%]
b) Mark the position of the tropopause, and describe characteristics of the
atmospheric temperature variation there.
[1%] + [1%]
5. a) Explain what the horizontal pressure gradient force is in the atmosphere.
Include the defining equation.
[3%]
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b) How does the horizontal pressure gradient force influence wind direction?
[1%]
6. a) Write down the Ideal Gas Equation for an air mass, and define (name)
each of the terms.
[3%]
b) What is an ‘adiabatic’ process?
[1%]
PLEASE TURN OVER
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7. On the diagram below, indicate the direction of the prevailing winds at the
Earth’s surface in each of the latitude bands shown:
a) 0° - 30°N;
b) 30°N - 60°N;
c) 60°N - 90°N
d) Use the letters “ITCZ” to indicate the approximate mean latitudes of the
Inter-Tropical Convergence Zone.
[4%, one mark per item]
8. a) How are the following caused:
i) Radiation fog;
[1%]
ii) Advection fog;
[1%]
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b) How is a ‘cap cloud’ formed?
[2%]
9. a) Define the Coriolis parameter, f, in equation form, naming each of the
terms.
[2%]
b) Sketch the variation of the Coriolis parameter with latitude. (Use a range of
90°S to 90°N).
(i.e., show the main form of the variation with latitude; detailed annotation is
not required)
[2%]
You can take Ω = 7.27 x 10-5 radians sec-1
PLEASE TURN OVER
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10. a) In meteorology, what is a ‘front’?
[2%]
b) Describe two characteristics associated with a front.
[2%]
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11. a) Geostrophic winds in the atmosphere are caused by a balance between
which two forces?
[2%]
b) On the following diagram of a low-pressure atmospheric system in the
Northern Hemisphere, mark the direction of the prevailing geostrophic winds.
[2%]
PLEASE TURN OVER
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12. a) Define potential temperature (θ) as function of local temperature (T)
and pressure (p).
[2%]
b) For an air mass at 500mb with measured temperature of -20°C, what would
be its potential temperature?
Use the following values:
Ideal Gas Constant, R = 8.31 J deg-1 mol-1
Specific heat capacity of dry air = cp = 1004 J deg-1 kg-1
Standard pressure, p0 = 1000 mb
[2%]
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13. a) What is ‘latent heat’?
[2%]
b) How can an air mass in the tropics gain latent heat?
[2%]
14. a) Name two oceanographic instruments that measure the temperature
and salinity of the ocean in-situ.
[2%]
b) Name two oceanographic instruments that measure current velocity in-situ.
[2%]
PLEASE TURN OVER
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15. Explain why Western Europe is warmer than the East Coast of North
America at the same latitude in winter.
[4%]
16. a) Why is ocean circulation important for the Earth’s climate?
[3%]
b) Which geographical features result in surface ocean circulation being
different from atmospheric circulation?
[1%]
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17. a) How are western boundary currents different to eastern boundary
currents?
[2%]
b) Name one western boundary current and one eastern boundary current.
[2%]
18. a) The density of seawater is primarily dependent on which two
properties?
[2%]
b) How does increasing the value of these two properties change seawater
density?
[2%]
PLEASE TURN OVER
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19. a) Where in the watercolumn is the mixed layer?
[1%]
b) Would you expect to find a pycnocline in the mixed layer?
[1%]
c) What processes cause the mixed layer?
[2%]
20. You have built an oceanographic instrument designed to withstand a
pressure of 104 kPa. Unfortunately, the cable connecting it to the ship snaps
and the instrument sinks 4000 m to the seabed. At what depth does the
instrument implode under pressure? Assume acceleration due to gravity is
9.81 m s-2 and the density of seawater is 1025 kg m-3.
[4%]
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21. a) Draw a diagram of a Northern Hemisphere subtropical gyre, including
the direction of circulation and the locations of high and low sea-surface.
[2%]
b) At one particular location in the eastern boundary current, draw arrows
indicating the direction of the Coriolis force, and the direction of the horizontal
pressure gradient force.
[2%]
PLEASE TURN OVER
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22. a) A parcel of water at 50°S is in a geostrophic current. The Coriolis
acceleration (Coriolis force per unit mass) acting on the parcel of water is
-2x10-5 m s-2. How fast is the parcel of water moving? Assume the Earth’s
angular rotation rate is 7.27 x 10-5 radians per second.
[3%]
b) If the Coriolis is force directed West to East, in which direction is the parcel
of water moving?
[1%]
23. The wind is blowing North to South along the coast of California on the
western side of North America.
a) In which direction will the surface water be flowing?
[1%]
b) Will this cause upwelling or downwelling?
[1%]
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c) Would you expect there to be little or lots of primary productivity in the
region? Why?
[2%]
24. Explain the difference between short (deep-water) waves and long
(shallow-water) waves, with regard to wavelength and phase-speed.
[4%]
25. a) Tides are long waves. Calculate the phase speed of the tide in 2000 m
of water? Assume acceleration due to gravity is 9.81 m s-2.
[3%]
b) What happens to the phase speed of the tide when it reaches the shallow
continental shelf?
[1%]
END OF PAPER
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