storm surge storm of scientific models and visualization Alabama Course of weather and climate cyclones. accompany hurricanes.

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1 A lesson about hurricanes, storm surge, and coastlines using storm surge model animations OBJECTIVE: Students will become knowledgeable of hurricane formation and physics as well as hurricane effects to coastal communities. The student activity focuses on hurricane storm surge variation within different coastal communities. Students will gain an understanding of scientific models and visualization ns and their value in the research of natural systems. Students will use visualizations to infer data about changing storm surge elevations during a model hurricane. National Science Content Standards: : Science and Technology Content Standard, Grades 9 12: Abilities of technological design Science and Technology Content Standard, Grades 9 12: Understandings about science and technology Science in Personal and Social Perspectives, Grades 9 12: Natural and human induced hazards Science in Personal and Social Perspectives, Grades 9 12: Science and technology in local, national, and global challenges Unifying Concepts and Processes, Grades 9 12: Evidence, models, and explanation Unifying Concepts and Processes, Grades 9 12: Change, constancy, and measurement Alabama Course of Study Science Standards: Aquascience Elective Core 2, Grades 9 12: Relate geological and hydrological phenomena and fluid dynamics to aquatic systems Earth and Space Science Elective Core 2, Grades 9 12: Describe effects on weather of energy transfer within and among the atmosphere, hydrosphere, biosphere, and lithosphere. Geology Elective Core 14, Grades 9 12: Explain the interaction of the continuous processes of waves, tides, and winds with the coastal environment. Marine Science Elective Core 4, Grades 9 12: Recognize interactions between the atmosphere and the ocean Ocean Literacy Principles: Essential Principle 3: The ocean is a major influence on weather and climate a. The ocean controls weather and climate by dominating the Earth s energy, water and carbon systems. b. The ocean absorbs much of the solar radiation reaching Earth. The oceann loses heat by evaporation. This heat loss drives atmospheric circulation when, after it is released into the atmosphere as water vapor,, it condenses andd forms rain. Condensation of water evaporated from warm seas provides the energy for hurricanes and cyclones. Climate Literacy Principles: Essential Principle 2: Climate is regulated by complex interactions among components of the earth system b. Covering 70% of Earth s surface, the ocean exerts a major control on climate by dominating Earth s energy and water cycles. Essential Principle 5: Our understanding of the climate system is improved through observations, theoretical studies, and modeling. c. Observations, experiments, and theory are used to construct and refine computer models that represent the climate system and make predictions about its future behavior. Essential Principle 7: Climate change will have consequences for the earth system and human lives a. Sea level rise increasess the risk of damage to homes and buildings from storm surges such as those that accompany hurricanes.

2 HURRICANES ( BACKGROUND INFORMATION FROM / AND ) Hurricanes are a type of tropical cyclone. A tropical cyclonee is a rotating, organized system of clouds and thunderstorms that originates over tropical or subtropical waters and has a closed low level circulation. Tropical cyclones rotate counterclockwise in thee Northern Hemisphere. They are classified as follows: Tropical Depression: A tropical cyclone with maximum sustained winds of 38 mph (33 knots) or less. Tropical Storm: A tropical cyclone with maximum sustained winds of 39 to 73 mph (34 to 63 knots). When a cyclone becomes a tropical storm, itt is given a name by the World Meteorological Organization. (To see a current list of cyclone names for the next 6 years, visit // shtml) Hurricane: A tropical cyclone with maximum sustained winds off 74 mph (64 knots) or higher. In the western North Pacific, hurricanes are called typhoons; similar storms in the Indian Ocean and South Pacificc Ocean are called cyclones. Major Hurricane: A tropical cyclone with maximum sustained winds of 111 mph (96 knots) or higher, corresponding to a Category 3, 4 or 5 on the Saffir Simpson Hurricane Wind Scale. Retired storm names: / 2 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

3 Hurricanes are low pressure systemss that can pack wind speeds of overr 160 miles ( 257 kilometers) an hour and unleash more than 2.4 trillion gallons (9 trillion liters) of rain a day. Hurricanes begin as tropical disturbances in warm ocean waters with surface temperatures of at least 80 degrees Fahrenheit (26.5 degrees Celsius). These low pressure systems are fed by energy from the warm seas. Hurricanes are enormous heat engines that generate energyy on a staggering scale. They draw heat from warm, moist ocean air and release it through condensation of water vapor in thunderstorms. Hurricanes spin around a low pressure center known as thee eye. Sinking air makes this 20 to 30 mile wide (32 to 48 kilometer wide) area notoriously calm. But the eyee is surrounded by a circular eye wall that hosts the storm s strongest winds and rain. These storms bring destruction ashore in many different ways. When a hurricane makes landfall it often produces a devastating storm surge that can reach over 20 feet (6 meters) high and extend nearly 100 miles (161 kilometers). Ninety percent of all hurricane deaths result from storm surges. A hurricane s high winds are also destructive and may spawn tornadoes. Torrential rains cause further damage by spawning floods and landslides, which may occur many miles inland. The best defense against a hurricane is an accurate forecastt that gives people time to get out of its way. The National Hurricane Center issues hurricane watches for storms that may endanger communities, and hurricane warnings for storms that will make landfalll within 24 hours. The Atlantic hurricane season runs from June 1st to November 30th butt peaks from mid August to late October and averages five to six hurricanes per year. The Atlantic basin includes the Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. 3 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

4 STORM SURGE In the path ( FROM: / ) Along the coast, storm surge is often the greatest threat to life and property from a hurricane. In the past, large death tolls have resulted from the rise of the ocean associated with many of the major hurricanes that have made landfall. Hurricane Katrina (2005) is a prime example of thee damage and devastation that can be caused by surge. At least 1500 persons lost their lives during Katrina and many of those deaths occurred directly, or indirectly, as a result of storm surge. Factors Impacting Surge: Storm surge is produced by water being pushed toward the shore by the force of the winds moving cyclonically around the storm. The impact on surgee of the low pressure associated with intense storms is minimal in comparison to the water being forced toward the shore by the wind. The maximumm potential storm surge for a particular location depends on a number of different factors. Storm surge is a very complex phenomenon because it is sensitive to the slightest changes in storm intensity, forward speed, size ( radius of maximum winds RMW), angle of approach to the coast, central pressure (minimal contribution in comparison to the wind), and the shape and characteristics of coastal featuress such as bays and estuaries. Other factors which can impact storm surge are the width and slope of the continental shelf. A shallow slope will potentially produce a greater storm surge than a steep shelf. For example, a Category 4 storm hitting the Louisiana coastline, which has a very wide and shallow continental shelf, may produce a 20 foot storm surge, while the same hurricane in a place like Miami Beach, Florida, where the continental shelf drops off very quickly, might see an 8 or 9 foot surge. 4 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

5 Recommended website visit: animated cross sections of storm surge effects to different coastlines Adding to the destructive power of surge, battering waves may increase damage to buildings directly along the coast. Water weighs approximately 1,700 pounds per cubic yard; extended pounding by frequent waves can demolish any structure not specifically designed to withstand such forces. The two elements work together to increase the impact on land because the surge makes it possible for waves to extend inland. Additionally, currents created by tides combine with the waves to severely erode beaches and coastal highways. Buildings that survive hurricane winds can be damaged if their foundationss are undermined and weakened by erosion. In confined harbors, the combination of storm tides, waves, and currents can also severely damage marinas and boats. In estuaries and bayous, salt water intrusion endangers the public health, kills vegetation, and can send animals, such as snakes and alligators, fleeing from flooded areas. 5 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

6 SCIENTIFICC VISUALIZATION ( In the path FROM: // Scientific visualization, sometimes referred to in shorthand as SciVis, is the representation of data graphically as a means of gaining understanding and insightt into the data. It is sometimes referred to as visual dataa analysis. This allows the researcher to gain insight into the system that is studied in ways previously impossible. What it is not It is important to differentiate between scientific visualization and presentation graphics. Presentation graphics are primarily concerned with the communication of information and results in ways that are easily understood. In scientific visualization, we seek to understand the data. However, often the two methods are intertwined. From a computing perspective, SciVis is part of a greater field called visualization. This involves research in computer graphics, image processing, high performance computing, and other areas. The same tools that are used for SciVis may be applied to animation, or multimedia presentation, for example. As a science, scientific visualization is the study concerned with the interactive display and analysis of data. Often one would like the ability to do real time visualization of data from any source. As an emerging science, its strategy is to develop fundamental ideas leading to general tools for real applications. This pursuit is multidisciplinary in that it uses the same techniques across many areas of study. Scientific visualization is an integral part of the process of simulating natural phenomena. In the computational sciences, the main goal is to understand the workings off nature. In order to accomplish this, the scientist proceeds through a number of steps from observing a natural event or phenomenon to analyzing the results of the phenomena. Visual representation of thiss data is often indispensable in gaining an understanding of the process involved. Through the availability of increasingly powerful computerss with increasing amounts of internal and external memory, it is possible to investigate incredibly complex dynamics by means of ever more realistic simulations. However, this brings with it vast amounts of data. To analyze these data it is imperative to have software tools which can visualize thesee multi dimensional dataa sets. Comparing this with experiment and theory it becomes clear that visualization of scientific data is useful yet difficult. For complicated, time dependent simulations, the running of the simulation may involve the calculation of many time steps. It is necessary to visualize and store the results selectively so that we do not have to recompute the dynamics if we want to see the same scene again. The main reasons for scientific visualization are the following ones: it will compresss a lot of data into one picture (data browsing), it can reveal correlations between different quantities both in space and time, and it opens up the possibility to view the data selectively and interactively in real time. It is also very useful to have the possibility to interactively change the simulation parameters and immediately see the effect of this change throughh the new data. 6 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

7 In this lesson, students will be using scientific visualizations, animations of storm surge elevation changes as hurricanes approach the shoreline. It is important to explain thatt these animations are derivedd from MODEL hurricanes, available storm surge data and known information about the topography of a region and the bathymetryy of the coastline. These are NOT animations of real hurricanes that have hit the northern gulf coast,but rather a collection of data pieced together like a puzzle to create a picture of what COULD happen during a hurricane. Introduce your students to the animations by choosing one from the website and playing it in its entirety. Note that each animation is organized by landfall location first, then by storm intensity, and finally by zoom level. The storm track is shown by a dark red line, each dot corresponding to an hour of movement northward by the hurricane model. Be awaree that part off the activity is labeling specific locations on the map. Students can complete this portion of the activity with either an online map source such as Google Maps, or it can be completed with ann Atlas. Only a few of the place names appear on the animations. 7 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

8 Be sure to point out the key to the left hand side of the video for storm surge elevation above mean sea level. Water bodies will appear dark blue in the animation until the storm surge elevation begins to increase. Changes might be subtle, so encourage students to watch carefully. To aid your students in the activity, it might be of benefit to print off several color copies of the key below (a more detailed key than that of the animation). Seee page 9 for a printer friendly sheet.. FOR THIS ACTIVITY This lesson must be done with the use of a computer lab, orr used as a take home exercise for students with after school computer access. The exercisee could be done with a single computer as a teacher lead activity. This activity assumes a general working knowledge of a computer video player. If your students are not familiar with the program, a brief tutorial prior to starting the activity is recommended. Be sure remind your students that pausing and replaying the animations might be necessary to answer some questions. 8 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

9 9 Page Northern Gulf Coast Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

10 : KEY NAME: TEACHER KEY DATE: In this exercise you will be watching several storm surge animations from hurricane models as they approach the Gulf coast. You will see how storm surge changes with coastline shape and hurricane intensity. If you have a hurricane of the same strength and speed headed towards the coastline, the storm surge can be drastically different depending on the bathymetry off the ocean (shape/depth of the ocean floor) and the topography of the coast (shape/elevation of the land). Look at the map of the northern Gulf of Mexico on the next page. Before watching the hurricane model animations, you will need to know where these landmarks are located along the northern Gulf of Mexico. 1. When a hurricane makes landfall, this is the geographic location that the eye of the hurricane moves onto land. The eye wall of a hurricane is where the most intensee wind speeds can be found. Label these locations in RED where our model storms will make landfall. Gulfport, MS Petit Bios Island, MS/AL Horn Island, MS Fort Morgann Peninsula, AL Dauphin Island, AL 2. Along the coast, storm surge is often the greatest threat from a hurricane. Storm surge is produced by water being pushed toward the shore by the force of thee winds rotating within the hurricane. Label the locations in BLUE that could be affected by the storm surge of the model hurricanes New Orleans, LA Biloxi, MS Lake Ponchartrain, LA Cat Island, MS Gulf Shores, AL Mobile, AL Mississippi River Mississippi River Delta Gulf of Mexico Pascagoula, MS Mobile Tensaw Delta Chandeleur Islands, LA Mobile Bay, AL 1 Page Student Worksheet Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

11 : KEY Label the map of the northern Gulf of Mexico with the locations listed on page 1. 2 Page Student Worksheet Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

12 5. Look at the map on page 2. Make a hypothesis about the storm surge elevation of a hurricane as it approaches the coastline. Do you think storm surge will increase, decrease, or stay the same? Explain your answer. A student s hypothesis should be scored with completion points. If theirr prediction is explained, regardless of accuracy, all points should be awarded. As a storm approaches the coastline, storm surge elevation increases due to the decreasing depth of the ocean. As the hurricane moves into shallow water, the surge is pushed up onto the continental shelf, and then into low lying coastal areas. In the path : KEY 3. Look at the map on page 2. Make a hypothesis about the landfall location (question 1) that will have the most severe and widespread storm surge during a category 4 storm. Explain your hypothesis. A student s hypothesis should be scored with completion points. If theirr prediction is explained, regardless of accuracy, all points should be awarded. The correct answer after watching the animations is Gulfport, MS. This model category 4 storm has the widest ranging 12ft (+) storm surgess it moves onto land. Horn Island, MS could also be an acceptable answer, though not quite as severe. 4. Look at the map on page 2. The Mississippi River Delta is a very low lying area of the Gulf Coast. Make a hypothesis about the maximum storm surge elevation in the Mississippi River Delta while a hurricane passes. How might the storm surge elevation compare at this location compared to the landfall locations? Explain your answer. A student s hypothesis should be scored with completion points. If theirr prediction is explained, regardless of accuracy, all points should be awarded. Most students will assume that low lying terrain automatically equals high surge elevations. In the case of the Mississippi River Delta, it has a surge during all model storms but the maximum depth was predicted to be only 5 feet. When hurricanes cross the Mississippi River Delta, the surge has a greater amount of water over which to dissipate, preventing a pile up of storm surge. 3 Page Student Worksheet Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

13 : KEY Now it is time to watch the animations of storm surge as each of the hurricane models approach land. There are five landfall locations for our model storms: Gulfport, MS; Horn Island, MS; Petit Bois Island, MS/AL; Dauphin Island, AL; and Fort Morgan Peninsula, AL. Each landfall location has model animations for a weaker storm (Category 2 3, approximate sustained winds of 110mph) and a stronger storm (category 4, approximate winds around 145mph). The depth surge is measured in height above mean seaa level (MSL)) and shown with a color code shown on the left of every video. As you watch the animation, you will see the storm progress along the storm track line, and the color of the water change as the storm surge depth changes. There is a zoomed in map and a zoomed out map for each model run. Use the animation that best answerss each question. 6. Answer the following questions while watching the hurricane storm surge model animations. Fill in the tables for each storm surge model. LANDFALL LOCATION Gulfport, MS If there was no storm surge in a given location, fill in the box with [0 feet]. Mobile Tensaw Delta, AL the Mississippi River Delta Which Gulf Coast city had the highest surge elevations? How high? Maximum storm surge depth at Gulfport, MS Category 2 3 Hurricane 4 5ft 3 4ft Biloxi/Pascagoula, 6 7ft 5 6ft Category 4 Hurricane 8 9ft 4 5ft Biloxi/Pascagoula, 12ft 9 10ft LANDFALL LOCATION Horn Island, MS Mobile Tensaw Delta, AL the Mississippi River Delta Which Gulf Coast city had the highest surge elevations? How high? Maximum storm surge depth at Horn Island, MS Category 2 3 Hurricane 4 5ft 2 3ft Pascagoula, 6ftt 3 4ft Category 4 Hurricane 10 11ft 2 3ft Pascagoula, 12ft 9 10ft 4 Page Student Worksheet Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

14 : KEY 6. (continued) Answer the following questions while watching the hurricane storm surge model animations. Fill in the tables for each storm surge model. If there was no storm surge in a given location, fill in the box with [0 feet]. LANDFALL LOCATION Petit Bois, MS/AL Mobile Tensaw Delta, AL the Mississippi River Delta Which Gulf Coast location had the highest surge elevations? How high? Maximum storm surge depth at Petit Bois, MS/AL Category 2 3 Hurricane 4 5ft 2 3ft Mobile, AL 4 5ft 2 3ft Category 4 Hurricane 9 10ft 4 5ft Pascagoula/ /Dauphin Isl 10 12ft 8 9ft LANDFALL LOCATION Dauphin Island, AL Mobile Tensaw Delta, AL the Mississippi River Delta Which Gulf Coast location had the highest surge elevations? How high? Maximum storm surge depth at Dauphin Island, AL Category 2 3 Hurricane 5 7ft 1 2ft Mobile, AL 5 7ftt 1 2ft Category 4 Hurricane 9 10ft 2 3ft Ft Morgan, AL 10 11ft (Mobile, AL 9 10ft also an answer) 7 8ft LANDFALL LOCATION Fort Morgan, AL Mobile Tensaw Delta, AL the Mississippi River Delta Which Gulf Coast city had the highest surge elevations? How high? Maximum storm surge depth at Fort Morgan, AL Category 2 3 Hurricane 0.2 2ft 0.2 2ft Gulf Shores, AL 4 5ft 3 4ft Category 4 Hurricane 4 5ft 0.2 2ft Gulf Shores, AL 10 12ft 9 10ft 5 Page Student Worksheet Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

15 : KEY 7. Which landfall location appeared to have the most severe storm surge during a category 4 model hurricane? How did this compare with your hypothesis in question 3? The correct answer after watching the animations is Gulfport, MS. This model category 4 storm has the widest ranging 12ft (+ +) storm surges it moves onto land. Horn Island, MS could also be an acceptable answer, though not quite as severe. Students should compare to their hypothesis in their answer. 8. Find Mobile Bay and the Mobile Tensaw Delta, Alabama in the animations and review the tables in question 5. Which landfall location(s) had the strongest storm surge in Mobile Tensaw Delta area? Petit Bois Island, MS/AL, Dauphin Island, AL (both 9 10 ft surge elevation) Did the path of this storm pass through Mobile Bay?? NO Why do you think this landfall location(s) had the greatest impact on storm surge in Mobile Bay? The most severe side of a hurricane in the Northern Gulf of Mexico coast is the eastern side due to the counterclockwise rotation, and the source of hurricanee power coming from over the ocean. Mobile Bay was located on the east side of both s, but still relatively close to the landfall location. When does the maximum surge occur? ( before landfall, during landfall, after landfall) Where in the bay does maximum storm surge occur?? Northern most part (the delta) Why do you think the highest surge occurs primarilyy in this location? Explain your answer. It is the most shallow part of the bay, and the water is funneled up into this area, concentrating the surge. 9. From the predictions of these models, which side would be more intense, the eastern side or the western side? Why would this be? Explain your answer using what you know about hurricanes. The most severe side of a hurricane in the Northern Gulff of Mexico coast is the eastern side due to the counterclockwise rotation, and the source of hurricane power coming from over the ocean. 6 Page Student Worksheet Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama

16 : KEY 10. Look at your hypothesis in question 4. Were you correct about the Mississippi River Delta and storm surge? Why or why not? Did the animations surprise you? A student s hypothesis comparison should reference their original answer in question 4, as well as explain the correct answer after watching the animations. A brief reflection should be includedd with their reaction to the animations. The Mississippi River Delta has a surge during all model storms but the maximumm depth was predicted to be only 5 feet. When hurricanes cross the Mississippi River Delta, the surge has a greater amount of water over which to dissipate, preventing a pile up of storm surge. 11. Look at your hypothesis in question 5. Were you correct? Why or why not? What happened to the model storm surge as the storms traveled through the Gulf of Mexico? A student s hypothesis comparison should reference their original answer in question 5, as well as explain the correct answer after watching the animations. An explanation of storm surge changes should be included. As a storm approaches the coastline, storm surge elevationn increases due to the decreasing depth of the ocean. As the hurricane moves into shallow water, thee surge is pushed up onto the continental shelf, and then into low lying coastal areas. 12. Watch one of the category 4 hurricane animations. How do the barrier islands affect storm surge as a hurricane approaches shore? Barrier Islands act as the initial landfall point for hurricanes. Storm surges reach barrier islands first though in these models, they are often NOT the location of the most severe storm surge. The Chandeleurs act as a shield for the LA coast, and as the western model storm's progress through the Gulf coast, they appear to slow the storm surge progression to the west. 13. How do models of storm surge and hurricanes benefit scientific research? Models allow scientist to study the possible interactions off different coastlines with storm surge and varying hurricanes. They allow for research and understanding without the need for a real hurricane to hit coastal areas. Could be used as a guide for city officials and emergency personnel in the event of a storm. 7 Page Student Worksheet Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab, Alabama