SO422
Nearshore Oceanography
Fall 2001 Exam
1
Attachment:
Wave equations
table
Read all questions carefully. Full credit on the problems
require that your method be clearly identifiable. For the short answer questions insure that
your answer is complete and concise, and covers the key points. You will be graded by how well you show an
understanding of the key concepts of the course.
5 definitions @4 20 ________
Problem 30 ________
short
answers @5, 10 and 20 50 ________
TOTAL 100 ________
Budget your time. This exam
can be done if you know what you are doing, but do not waste time on a question
you do not understand. On the short answers note that you have some choices on which
questions to answer. Note also
that the last short answer is worth 20 points, so you take more care in that
answer.
(20) Definitions. Briefly define 5 of the following terms with
no more than a single sentence showing that you clearly understand its
importance. If you use a mathematical
relationship, also explain its importance or significance:
·
Dissipative
profile:
·
Groin:
·
Orthogonals:
·
Refraction:
·
Shoaling
·
Sorting:
·
SPM
or CEM:
(30) A wave has a period T=11.3 sec, and passes a wave gauge in
water d=15 m deep. At the gauge H15=5.0 m, and the angle of
attack a15=28°. All
calculations on this page use these values, and unless specifically stated you
are not to provide answers for deep water.
The bottom slopes uniformly and smoothly offshore. For full credit you must show your method on all questions. If you cannot solve for something you need,
assume a reasonable value and proceed.
(3) For this wave, how deep does the water have to be for it
to be considered deep and the wave a deep water wave?
(5) What will be the wavelength of the wave at this depth (not in deep water)?
(2) What will be the speed of the wave at this depth (not in deep water)?
(5) What will be the orientation a0
of the wave in deep water.
(5) What will be the height H0 of the wave in deep water?
(3) Will the wave break before or after reaching this depth?
(3) At what depths will this wave transition from deep to
intermediate depth, and from intermediate toshallow?
(4) Answer one of the following questions:
·
At
what depth would this wave a speed of 8 m/sec? You may neglect refraction for
this answer.
·
At
what depth will this wave have its minimum height? You may neglect refraction
for this answer.
·
Is
there any way the wave could have the same height at two different depths? You must defend your answer, and may neglect
refraction for this answer.
Short Answer. Answer the following questions as directed
with concise, complete answers. You
should use appropriate terminology and concepts.
Answer the question on this page. It is
worth 10 points.
1.
These two graphs show the variation in a single parameter as two waves
come ashore. Suggest what parameter is
depicted, what variable(s) in the wave climate is (are) different for the two
waves, and why each graph has the shape it does.
Answer the question on this page. It is
worth 10 points.
2. These diagrams show beach profiles measured at Duck, NC, Jan and Aug 1984. Identify which profile is which, how you could tell, and what causes the difference between the two profiles?
Answer two of the next three questions. Each is worth 5 points.
3a. This diagram below shows a portion of
the coastline of
3b. What is the feature depicted by this diagram, and how does it form.
3c. What does this
diagram depict? (Use correct
terminology, and describe the process involved.)
You must answer one of the two
questions on this page or the next page.
It is worth 20 points.
4a. This diagram shows
the development of a coastal feature(s).
Discuss:
- What is developing;
- The different
environments depicted;
- The processes
operating.
4b. This diagram shows four possibilities for a coastal pass. Discuss:
- What differs in the
four cases?
- What is required to
keep the pass stationary without building jetties?
