Instructor Manual For
Environmental Geology 5 th
Edi�on By James Reichard
(All Chapters
1-16, 100% Original Verified
A+ Grade)
Instructor Manual Part 1: Chapter 9-16
Instructor Manual Part 2: Chapter 1-8
All Chapters Arranged Reverse.
,Chapter 09 – Coastal Hazards
CHAPTER 9
COASTAL HAZARDS
Chapter Outline
Introduction
Shoreline Characteristics
Coastal Processes
Tides
Currents
Waves
Wave Refraction and Longshore Currents
Shoreline Evolution
Barrier Islands
Coastal Hazards and Mitigation
Hurricanes and Ocean Storms
Tsunamis
Rip Currents
Shoreline Retreat
Box Readings:
Case Study 9.1: New Orleans and the Next Hurricane Katrina
Case Study 9.2: The 2017-2018 String of Powerful U.S. Hurricanes
Student Learning Outcomes
1. Explain the fundamental differences between ocean tides, currents, and waves.
2. Describe how waves form, travel through open water, and change when they approach shore
and enter shallow water.
3. Discuss how longshore currents develop, and explain the longshore movement of sediment.
4. Characterize the basic way hurricanes form and the three major hazards they pose to humans.
5. Explain why the number of hurricane-related deaths has decreased in recent years but
property losses have increased.
6. Characterize how tsunamis form, and explain why they pose such a hazard to people and
property.
7. Identify the basic cause of shoreline retreat, and discuss how humans are making the problem
worse.
8. Describe the different types of coastal engineering techniques, their purposes, and their
undesirable consequences.
1
© McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.
,Chapter 09 – Coastal Hazards
Chapter Summary
In this chapter, students are introduced to processes and hazards that are associated with coastal
areas. In the first section waves, tides, and currents are explained with an emphasis on the energy
and mechanisms involved. Longshore currents are addressed specifically because they result in
longshore drift, which is responsible for the movement of sediment along a shoreline. Coastal
hazards—hurricanes and ocean storms, tsunamis, and rip currents—are described, including their
origins, associated dangers and mitigation mechanisms. Engineering techniques used to protect
property and shorelines are also discussed in conjunction with their unintended consequences to
society.
The first case study in this chapter summarizes the disaster in New Orleans resulting from
Hurricane Katrina and describes the possibility of a similar, but more deadly event occurring
there in the future. The second case study discusses the unusual string of powerful hurricanes
that made landfall in the United States in 2017 and 2018, and whether these events can be
attributed to global warming and climate change.
Student Activity
Find a shop vacuum cleaner that can be used for both wet and dry cleanups. Next, take a standard
9-by-13-inch cake pan, place it on a level surface, and fill it with water to about a half-inch from
the top. Now turn on the wet/dry shop vacuum and, holding the nozzle about a foot above the
center of the pan, slowly lower it toward the surface of the water until you see the water surface
start to rise in the center of the pan. Explain the basic principle involved, and describe how the
observed effect relates to storm surge in a hurricane.
Next, change the vacuum setup so air blows out the nozzle—most models let you do this. Turn it
on and, holding the nozzle horizontally about 2 feet from the pan, blow air across the surface of
the water. What happens to the water surface this time? How is this effect similar to storm surge
in a hurricane? Which setup produced the largest storm surge?
Critical Thinking Questions
• Have you ever been on boat sitting on open water when the wake from a passing boat
causes yours to move up and down, and at the same time roll sideways? What exactly is it
about wave energy passing through water that makes your boat rock back and forth?
Wave energy causes water molecules to move in a circular or elliptical manner within a body
of water. As a wave passes, a boat will rise and fall, whereas the circular motion of the
water molecules causes the boat to roll in the direction of the passing wave.
• Beach drift occurs when surf pushes sand grains up the beach at an angle, and then, as the
water flows back to the sea, the grains are carried straight down the beach. What happens to
this process when wave energy increases dramatically during a storm? How does this
increase affect the beach?
2
© McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.
, Chapter 09 – Coastal Hazards
Increased wave energy expands the size of the beach zone where the sand grains are in
motion. This results in a greater volume of sand being transport, thereby increasing beach
drift.
• Suppose you head to the beach to go swimming, but find that the wave energy is
particularly high and generating heavy surf. What should you look for in the surf zone so
that you can avoid getting caught in a dangerous rip current?
You should look for zones where incoming waves are not breaking into surf. You need to
avoid these areas as this is where outgoing rip currents are interfering with the formation of
surf.
Your Environment: YOU Decide
Natural shoreline retreat poses a serious threat to commercial and domestic structures in coastal
areas, such as beachfront resorts, condominiums, and private homes. Due to the importance of
tourism to the economy of many coastal regions, state and federal agencies often spend tax
dollars on various engineering projects designed to reduce shoreline erosion and retreat. These
projects include building groins and seawalls and engaging in beach nourishment. Ultimately,
these engineering projects are government subsidies that encourage the construction of expensive
resorts and vacation homes. In the past, funding came from general tax revenues, but today more
is coming from user taxes that target people who patronize the businesses that benefit from the
shoreline engineering projects.
Discuss whether everyone in society should share the costs of government projects to reduce
shoreline erosion (i.e., a general tax) or the costs should be covered by a user tax. Would it be
even better not to have commercial buildings and homes built directly on the shoreline in the first
place, but instead require them to be built farther back? Explain why.
Answers regarding a general versus a user tax will vary depending on whether one thinks the
economic value of coastal tourism benefits only the immediate region or society as a whole. For
those who prefer a purely natural coastline, hopefully they will recognize that this is feasible only
for select areas set aside specifically for this purpose.
3
© McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.
Environmental Geology 5 th
Edi�on By James Reichard
(All Chapters
1-16, 100% Original Verified
A+ Grade)
Instructor Manual Part 1: Chapter 9-16
Instructor Manual Part 2: Chapter 1-8
All Chapters Arranged Reverse.
,Chapter 09 – Coastal Hazards
CHAPTER 9
COASTAL HAZARDS
Chapter Outline
Introduction
Shoreline Characteristics
Coastal Processes
Tides
Currents
Waves
Wave Refraction and Longshore Currents
Shoreline Evolution
Barrier Islands
Coastal Hazards and Mitigation
Hurricanes and Ocean Storms
Tsunamis
Rip Currents
Shoreline Retreat
Box Readings:
Case Study 9.1: New Orleans and the Next Hurricane Katrina
Case Study 9.2: The 2017-2018 String of Powerful U.S. Hurricanes
Student Learning Outcomes
1. Explain the fundamental differences between ocean tides, currents, and waves.
2. Describe how waves form, travel through open water, and change when they approach shore
and enter shallow water.
3. Discuss how longshore currents develop, and explain the longshore movement of sediment.
4. Characterize the basic way hurricanes form and the three major hazards they pose to humans.
5. Explain why the number of hurricane-related deaths has decreased in recent years but
property losses have increased.
6. Characterize how tsunamis form, and explain why they pose such a hazard to people and
property.
7. Identify the basic cause of shoreline retreat, and discuss how humans are making the problem
worse.
8. Describe the different types of coastal engineering techniques, their purposes, and their
undesirable consequences.
1
© McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.
,Chapter 09 – Coastal Hazards
Chapter Summary
In this chapter, students are introduced to processes and hazards that are associated with coastal
areas. In the first section waves, tides, and currents are explained with an emphasis on the energy
and mechanisms involved. Longshore currents are addressed specifically because they result in
longshore drift, which is responsible for the movement of sediment along a shoreline. Coastal
hazards—hurricanes and ocean storms, tsunamis, and rip currents—are described, including their
origins, associated dangers and mitigation mechanisms. Engineering techniques used to protect
property and shorelines are also discussed in conjunction with their unintended consequences to
society.
The first case study in this chapter summarizes the disaster in New Orleans resulting from
Hurricane Katrina and describes the possibility of a similar, but more deadly event occurring
there in the future. The second case study discusses the unusual string of powerful hurricanes
that made landfall in the United States in 2017 and 2018, and whether these events can be
attributed to global warming and climate change.
Student Activity
Find a shop vacuum cleaner that can be used for both wet and dry cleanups. Next, take a standard
9-by-13-inch cake pan, place it on a level surface, and fill it with water to about a half-inch from
the top. Now turn on the wet/dry shop vacuum and, holding the nozzle about a foot above the
center of the pan, slowly lower it toward the surface of the water until you see the water surface
start to rise in the center of the pan. Explain the basic principle involved, and describe how the
observed effect relates to storm surge in a hurricane.
Next, change the vacuum setup so air blows out the nozzle—most models let you do this. Turn it
on and, holding the nozzle horizontally about 2 feet from the pan, blow air across the surface of
the water. What happens to the water surface this time? How is this effect similar to storm surge
in a hurricane? Which setup produced the largest storm surge?
Critical Thinking Questions
• Have you ever been on boat sitting on open water when the wake from a passing boat
causes yours to move up and down, and at the same time roll sideways? What exactly is it
about wave energy passing through water that makes your boat rock back and forth?
Wave energy causes water molecules to move in a circular or elliptical manner within a body
of water. As a wave passes, a boat will rise and fall, whereas the circular motion of the
water molecules causes the boat to roll in the direction of the passing wave.
• Beach drift occurs when surf pushes sand grains up the beach at an angle, and then, as the
water flows back to the sea, the grains are carried straight down the beach. What happens to
this process when wave energy increases dramatically during a storm? How does this
increase affect the beach?
2
© McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.
, Chapter 09 – Coastal Hazards
Increased wave energy expands the size of the beach zone where the sand grains are in
motion. This results in a greater volume of sand being transport, thereby increasing beach
drift.
• Suppose you head to the beach to go swimming, but find that the wave energy is
particularly high and generating heavy surf. What should you look for in the surf zone so
that you can avoid getting caught in a dangerous rip current?
You should look for zones where incoming waves are not breaking into surf. You need to
avoid these areas as this is where outgoing rip currents are interfering with the formation of
surf.
Your Environment: YOU Decide
Natural shoreline retreat poses a serious threat to commercial and domestic structures in coastal
areas, such as beachfront resorts, condominiums, and private homes. Due to the importance of
tourism to the economy of many coastal regions, state and federal agencies often spend tax
dollars on various engineering projects designed to reduce shoreline erosion and retreat. These
projects include building groins and seawalls and engaging in beach nourishment. Ultimately,
these engineering projects are government subsidies that encourage the construction of expensive
resorts and vacation homes. In the past, funding came from general tax revenues, but today more
is coming from user taxes that target people who patronize the businesses that benefit from the
shoreline engineering projects.
Discuss whether everyone in society should share the costs of government projects to reduce
shoreline erosion (i.e., a general tax) or the costs should be covered by a user tax. Would it be
even better not to have commercial buildings and homes built directly on the shoreline in the first
place, but instead require them to be built farther back? Explain why.
Answers regarding a general versus a user tax will vary depending on whether one thinks the
economic value of coastal tourism benefits only the immediate region or society as a whole. For
those who prefer a purely natural coastline, hopefully they will recognize that this is feasible only
for select areas set aside specifically for this purpose.
3
© McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.
