hurricane. Alabama Course of weather and climate cyclones. accompany hurricanes.

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1 Visualizing hurricanes A multimedia lesson about hurricanes, storm surge, and scientific visualizations from models OBJECTIVE: Students will able to differentiate between storm surge elevation and inundation and as a result complete inundation calculations. Students will gain an understanding of scientific visualizations and their value in the research of natural systems. Studentss will use current technologies with a scientific visualization tool to infer data about coastal storm surge and inundation during a modeled 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. 1 Page

2 Students THE PATH STORM SURGE Visualizing hurricanes should have a basic understanding of hurricane formation and physics. IN OF THE STORM is a NGCHC/DHP lesson designedd to precede VISUALIZING HURRICANES, but not necessary to completee the lesson. ( FROM: / ) BEFORE STARTING THIS LESSON: BACKGROUND INFORMATION 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 surge of the low pressure associated with intense storms is minimal in comparison to the water being forced toward the shore by the wind. The maximum 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 features such as bays and estuaries. 2 Page

3 STORM SURGE, WAVE SETUP, STORM TIDE AND INUNDATION WAVE SETUP In addition to the rise in water caused by the forces of the storm, the effects of storm surge on land are compounded by the height and intensity of the waves thatt result in an increase in water elevation. It is important to note with your students the different between wave set up and wave height. height is the difference between the crest and the trough off a single wave. Wave Wave setup indicates the rise in the Mean Water Level, or sea level, due to wave generated onshore transport of water mass. When the waves break near the coast in the surf zone, the broken water mass gets piled up against the bench slope following conversion of kinetic energy to potential energy. As a result the water level for a considerable distance offshore rises. For this to happen a sustained wave attack of an hour or so is necessary so that the equilibrium surface gets formed. Calculation of wave setup is necessary to know whether low lying coastal areas would be flooded in stormy waves. ( from / 3 Page

4 TIDE and STORM SURGE Storm Surge and Tide: Storm surge is an abnormal rise of water generated by a storm, over and above the predicted astronomical tides. This rise in water level can cause extremee flooding inn coastal areas particularly when storm surge coincides with the normal highh tide, resulting in waterr levels in excess of 20 feet or more in some cases. Astronomical tides can lessen storm surge impacts iff the storm hits at a low tide. INUNDATIONN Storm surge is the increase in normal water elevation caused by the storm s winds and pressure, while inundation is the depth of water over what normally would be dry land. FOR EXAMPLE: The storm surge on a specific area of coastline could be 20ft. But the inundation close to the beach (sea level) will be different than the inundationn high atop a sand dune. Total possible inundation at location (x) will vary according to the elevation and includes all three factors: storm surge, tide level and wave setup. At the time of hurricane landfall, highh tides will have a positive value while low tides will have a negative value. If inundationn calculations are completed and the result is a negative value, that location will not experience flooding as a result of total storm surge. 4 Page

5 For the Visualizing Hurricanes activity, students will need to know and understandd the total possible inundation calculation: Total Possible Inundation = (Tide Level + Storm Surge + Wave Setup) Elevation A valuable visual for students is including variations of wavee set up and tide levels while keeping storm surge and elevation consistent. Inundation can vary drastically according to these factors even when the actual storm surge measuremen nts are equivalent. For the graphic above, a word problem could read as follows: Determine the total possible inundation for a home built at an elevation of 12ft above sea level. The approaching storm is predicted to have a storm surge of 14ft and a wave setup of 6ft. The storm is going to make landfall during a high tide of 2ft. 5 Page

6 SCIENTIFIC VISUALIZATION (FROM: Scientific visualization, sometimes referred to in shorthand as SciVis, is the representation of data graphically as a means of gaining understanding and insight into the data. It is sometimes referred to as visual data 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 of 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 this data has been often indispensable in gaining an understanding of the process involved. Through the availability of increasingly powerful computers 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 these multi dimensional data 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 compress 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 through the new data. 6 P age

7 REAL STORM SURGE VISUALIZATION TOOL The REAL (Rapid Estimates of Approaching Landfall) tool uses pre computed, high resolution model data to generate fast, accurate, time dependent and operation estimates of local storm surge. Currently, the REAL models include 500 models that concentrate on the Mississippi coast, but additional models for Gulf States are being added in the near future. The model runs are tested with storms simulations of known directional paths, minimum sea level pressure and maximum radius of wind fields (overall size of the storm). All model runs then examine variations of storm wind speed, wind direction, speed of forward motion, and maximum wind speed to the resulting storm surge and inundation occurring on land. Scientists have run hindcast models (comparing the REAL simulations to past datum from recorded hurricanes) and found that the REAL visualization tool has less than 20% error in its storm surge and inundation predictions. This makes REAL a useful tool for forecasting potential storm surge effects for approaching hurricanes. In using the REAL tool for this exercise, we will be importing the model run into Google Earth for a user friendly format. We will be looking at a storm model very similar to Hurricane Camille, which struck the Gulf coast in The model, Natasha, is similar to Camille in track 24 hrs prior to landfall, central pressure, and maximum radius of winds. It is important to note, for the REAL visualization tool, the surge depths include wave setup. All calculations assume a neutral (zero height) tide level. 7 P age

8 FOR THIS ACTIVITY This lesson must be done with the use of a computer lab, or used as a take home exercise for students with after school computer access. There is a PowerPoint for this lesson plan available to aid teachers in explaining the concepts. There are 2 different sets of worksheets for this lesson. Teach your students about the difference between storm surge and inundation. Students will need to have an understanding of storm surge math to complete the Inundate your Brain! worksheets. Discuss scientific visualizations with your students. Explain that they will be using a scientific visualization tool (REAL) to help them understand hurricane impacts to coastal communities. Introduce your students to the REAL tool in Google Earth, explaining each layer of the program and what it visualizes. The Visualizing Hurricanes worksheet is designed to guide students through the REAL tool. This activity assumes a general working knowledge of the Google Earth program. If your students are not familiar with the program, a brief tutorial prior to starting the activity is recommended. Expand it! HISTORY AND SCIENCE! Combine this activity with the interdisciplinary lesson from the NGCHC on Historical Hurricanes and Hurricane Camille. Have students use the REAL tool to compare the historical information from Hurricane Camille to the model run Natasha and draw comparisons between the two storms. Is Natasha a good model to compare to the known effects from Hurricane Camille? How does the Natasha model vary from past data and recorded accounts from Hurricane Camille? COASTAL HABITATS AND WETLANDS! Use the inundation Water Depth layer of the REAL visualization tool to discuss the benefits of certain types of habitats. Examine areas with significant wetland habitats, compared to heavily developed coastal areas and the resulting inundation in each area. Discuss how coastal development has changed the resiliency of coastal habitats and communities during hurricanes and other natural disasters. ENGINEERING! Using the storm surge depth Elevation layer and the inundation Water Depth layer, discuss methods of coastal engineering that could potentially affect how coastal areas are affected by hurricanes. Look for current structures (bridges, levees, sea walls) that might affect how the inundation levels affect the coastal communities during a storm. Predict how inundation levels might change if they were removed. 8 P age

9 KEY Inundate your brain! Name: date: 1 5. Label the following parts of the picture: Wave Setup Storm Surge Inundation Level Tide Level Mean Sea Level 6. Calculate the inundation level of a building located at an elevation off 11ft during a hurricane with a storm surge of 10 ft and a wave setup of 2ft. The hurricanee made landfall between low and high tide and the tide level was equal to mean sea level. (Tide level=0ft) INUNDATION = ( SURGE + WAVE SETUP + TIDE) (ELEVATION) Inundation= (10ft + 2ft + 0ft) 11ft = 1ft inundationn 9 Page

10 KEY Inundate your brain! (page 2) 7. Calculate the inundation level of a building located at an elevation of 15ft during a hurricane with a storm surge of 8ft and a wave setup of 3ft. The hurricane made landfall at a low tide of 5ft below mean sea level. Show your work. INUNDATION = (SURGE + WAVE SETUP + TIDE) (ELEVATION) Inundation = (8ft + 3ft +( 5ft)) 15ft = 9 ft There was NO INUNDATION 8. Calculate the inundation level of a building located at an elevation of 12ft during a hurricane with a storm surge of 8ft and a wave setup of 2ft. The hurricane made landfall at peak high tide of 5.5ft above mean sea level. Show your work. INUNDATION = (SURGE + WAVE SETUP + TIDE) (ELEVATION) Inundation = (8ft + 2ft + 5.5ft) 12ft = 3.5 ft inundation 9. Calculate the inundation level of a building located at an elevation of 12ft during a hurricane with a storm surge of 8ft and a wave setup of 2ft. The hurricane made landfall at peak low tide of 5.5ft below mean sea level. Show your work. INUNDATION = (SURGE + WAVE SETUP + TIDE) (ELEVATION) Inundation = (8ft + 2ft + ( 5.5ft)) 12ft = 7.5 ft There was NO INUNDATION 10. Based on your calculations in problems 6 9, and what you learned in class, can the tide table an the time a hurricane makes landfall make any difference in the amount of damaged caused by the storm surge? Explain your answer. There would most likely be less damaged from inundation if a hurricane makes landfall during low tide. Because sea level would already be below the mean, there would be a cushion for the surge. The surge would need to be greater than the absolute value of the low tide level to make any inundation on land. 10 P age

11 KEY Visualizing hurricanes STUDENT WORKSHEET TEACHER KEY 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 of 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 this data is often indispensable in gaining an understanding of the process involved. For this activity, you will be using a scientific visualization tool called REAL (Rapid Estimates of Approaching Landfall), to learn about the effects of storm surge to coastal communities. We will be visualizing a simulated hurricane model through Google Earth. Go to the NGCHC/ DISL storm surge website: Stormsurge.disl.org Click on the Student Resources link Download Instructions If your computer does not have Google Earth, you will need to download this program from the student resource page before starting. Find and select the Natasha vs. Camille link. When the Opening REAL Natasha vs. Camille.kmz dialog box opens, select OPEN with Google Earth. For younger grades, teachers might need to have the program pre set on the computers. BEFORE STARTING THE WORKSHEET: Turn off all layers by clicking the boxes EXCEPT those selected in My Places and the Primary Database in the Google Earth REAL Visualization KEY (next page). This will help the program run with greater speed and prevent an overabundance of information in the Google Earth Viewer. Throughout the exercise, you will need to turn off or turn on certain layers in My Places. If the box next to the layer is green, or has a green check mark, the layer is on and showing on the viewer. 11 P age

12 KEY Google Earth REAL Visualization Use this key throughout the activity to answer the questions. Click on the [+] to see more place/layer choices. 12 P age

13 KEY USING THE REAL VISUALIZATION TOOL IN GOOGLE EARTH, ANSWER THE FOLLOWING QUESTIONS Hurricane Camille struck the Gulf coast on August 17, When Camille made landfall near the mouth of the Mississippi River, it was a category 5 storm with sustained winds of 190 mph. While it was an intensely strong storm, it was relatively small in size. Of the 500 models of storms hitting the Mississippi coast, JOS6009D Hurricane Model Run Natasha was found to be the most closely correlated to Camille s historical track 24hrs prior to landfall. However, these tracks vary quite dramatically in their start and conclusion. Hurricane Camille s HISTORIC TRACK is shown by two track lines: Best Track is Camille s path up until 24hrs prior to landfall. This path is shown in teal moving into the Gulf of Mexico after passing over Cuba. FST Track is Camille s path from 24hrs prior to landfall through the time that Camille reached the Alabama Tennessee state border. JOS6009D is the model run of Hurricane Natasha designated by a green track line extending from the Bahamas through to the Mississippi Arkansas state border. 1. Using the image on Google Earth, give the coordinates where the historic track and model track first converge. (TIP: zoom in to get the most accurate coordinates located at the bottom of the screen) Latitude North: 27⁰ 08 N (27⁰ 08 N) approximately Longitude West: 88⁰ 15 W (88⁰ 15 W) approximately 2. Give the coordinates of Camille s historic track after landfall, where the Camille and the model track JOS6009D significantly diverge. Latitude North: 31⁰ 12 N (31⁰ 11 N) approximately Longitude West: 89⁰ 35 W (89⁰ 36 W) approximately 3. The REAL models are used to look at storm surge and inundation possibilities for the coast. The paths of the model run JOS6009D and Camille s historical track diverge after landfall. Why do you think this model was chosen as the closest match /correlation to the historic track? Because the models are looking at storm surge, the 24hrs prior to landfall are of the most important b/c storm surge occurs in front of a storm and during a storm. Surge begins to subside once the storm makes landfall. 13 P age

14 KEY Water levels in the REAL visualization tool are shown as a color gradient. The scale of this gradient is shown in the upper left corner of your Google Earth Viewer and measured in feet. Turn on (select) the Elevation layer under JOS6009D. The elevation layer shows the maximum storm surge level. It is named Elevation because it is a measurement of the elevation of water above the median sea level. This layer shows the maximum predicted level of storm surge during the entire track of the model storm. For the REAL program, the storm surge measurements include BOTH storm surge and wave setup. However, REAL assumes a neutral tide level of 0ft. 4. Looking at the Elevation layer and the coastline affected by model run JOS6009D, what is the maximum storm surge predicted by the model? APPROXIMATELY 18FT (Note: the scale goes up to 20ft +, however looking at the map, only depths of approximately 18ft are predicted) 5. Zoom into the area of the maximum storm surge elevation. Which two coastal towns in Mississippi would have the most severe storm surge depth from model run JOS6009D? PASS CHRISTIAN AND GULFPORT (LONG BEACH ACCEPTED ALSO) 6. From the predictions of this model, which side of the storm 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 EASTERN SIDE OF THE STORM HAS A MORE SEVERE STORM SURGE. STORM SURGE IS CAUSED FROM A COMBINATION OF WIND, PRESSURE AND FORWARD MOTION OF THE HURRICANE. THE EASTERN SIDE OF THE STORM IS THE MOST SEVERE PRIMARY DUE TO THE COUNTER CLOCKWISE ROTATION OF THE STORM BODY 7. Find Lake Pontchartrain in Louisiana. Does any storm surge from model run JOS6009D reach this estuary? If yes, what approximate depth does the surge reach? If no, why wasn t this area affected? YES, APPROXIMATELY 4 5 FEET 14 P age

15 KEY Turn off (un select) the Elevation layer under JOS6009D. Turn on (select) the Water Depth layer under JOS6009D. The Water Depth layer shows the maximum inundation level during the entire track of the model storm. Inundation for the REAL model is the height of water over land OR still waters such as marshes, rivers and inland lakes. Inundation = (storm surge + wave setup + tide (assumed to be zero)) (elevation of land OR still water) 8. Looking at the Water Depth layer and the coastline affected by model run JOS6009D, what is the maximum inundation depth predicted by the model? 12FT 9. Find Mobile Bay, Alabama on the map. What inundation depth does the model predict in Mobile Bay during model run JOS6009D? 2 5ft Where in the bay does inundation occur? NORTHERN MOST PART OF THE BAY (and edges) Why do you think the inundation occurs primarily in this location? Explain your answer. This area is a very shallow delta/marsh/wetland region, so it would flood easier with any storm surge (shallow coastlines flood easier than deeper coastlines), also located far away from the storm so storm surge would be less severe 10. Find Bay St. Louis, Mississippi on the map. Where is Bay St. Louis located in relation to the path of model run JOS6009D? EAST OF THE TRACK Is inundation at this location just at the edges of the bay? NO, IT GOES INLAND What landforms does the storm surge seem to follow? Why? Explain your answer. FOLLOWS RIVERS INLAND, lowest elevation, easier for water to flow inland 15 P age

16 KEY Leave the Water Depth layer on. Turn on (select) the Hydrograph layer under JOS6009D The Hydrograph layer predicts the time and depth of the storm surge at different USGIS tide stations (United States Geological Survey). The stations are marked by bright green squares. When you click on the green station square, a graph will appear showing the change in water depth during the track of the model storm. The passing of the storm is marked by a red landfall line. This is an example of a hydrograph from the REAL tool. The time since the model hurricane formed is on the x axis. The water elevation at the specific USGIS tide station is on the y axis. This shows, in graph form, how the water levels change due to storm surge during the approach and landfall of the hurricane. 11. Select three stations from the map. Give the station name, the hour of storm landfall, the maximum water elevation predicted, and the hour of maximum water depth for each station. Station Name/Location Storm Landfall Maximum water Hour of Max Water (hour) elevation (ft) Elevation ANSWERS WILL VARY 139 hrs ANSWERS WILL VARY ANSWERS WILL VARY 139 hrs 139 hrs 16 P age

17 12. Using the chart in question 11, did the maximum water elevation occur before, during or after the landfall of the model storm at each station? Give an explanation why the maximum storm surge elevation occurred when it did for each station. Location: ANSWERS WILL VARY Maximum elevation occurred (BEFORE or AFTER ) the model hurricane made landfall. Why did max surge elevation occur at this time? KEY Location: Maximum elevation occurred (BEFORE or AFTER ) the model hurricane made landfall. Why did max surge elevation occur at this time? Location: Maximum elevation occurred (BEFORE or AFTER ) the model hurricane made landfall. Why did max surge elevation occur at this time? 17 P age

18 KEY Turn off (un select) the Hydrograph layer under JOS6009D. Turn off (un select) the Water Depth layer under JOS6009D. Turn on (select) the Time Series of Elevation layer under JOS6009D NOTE: Depending on the speed of your computer, this layer might not function properly. You can still answer questions 13 and 14. The Time Series of Elevation layer shows a time lapse of the model storm Natasha as it approaches shore. By hovering over the Elevation Color Key on the top left of the Google Earth viewer, a Play Bar will appear: this allows you to watch the changes of the storm surge as the model storm follows the path. Click on the clock with the triangle to start the animation. (4 th symbol in the gray box.) Watch the time series of the model storm as it approaches shore between 8/16/ :00pm and 8/18/ :00pm. Do this at least 2 3 times. (If you are having trouble viewing the animation, make sure all other browsers and unnecessary programs are closed) 13. Thinking about the uses of the REAL Storm Surge Visualization Tool, who might benefit the most from the predictions of this program? ANSWERS WILL VARY 14. What are 3 advantages of the REAL Storm Surge Visualization Tool for coastal communities? What are three disadvantages of this tool for coastal communities? ANSWERS WILL VARY 18 P age

19 School: Grade: Male / Female Pre / Post circle NGCHC Hurricane Lesson Plan Pre/Post Test 1. The representation of data in a graphical and interactive way as a method of gaining understanding and insight into the data is called. a. Scientific Graphing b. Scientific Visualization c. Presentation Graphics d. None of the above 2. What is an example of a model? a. A mobile of the solar system b. An equation for a line c. A diagram showing the effects of pollution on a pond d. All of the above 3. Which type of coastline has a greater potential for large storm surge? a. A wide and shallow coastline b. A narrow and deep coastline c. Coastline does not have an effect on storm surge d. Both shallow and deep coastlines have an equal potential for large storm surge. 4. What is the term for an increase in water elevation, in addition to storm surge, caused by the storm s waves? a. Wave height b. Wave depth c. Wave set up d. Wave elevation 5. What factors can affect storm surge? a. Storm winds b. Air pressure within the storm c. Forward speed of the storm d. All of the above Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab

20 School: Grade: Male / Female Pre / Post circle 6. What does R.E.A.L. stand for? a. Rapid Estimates of Approaching Landfall b. Recommended Elevation Above Land c. Realistic Estimates of Amplitude and Length d. None of the above 7. What is the term for the depth of water over dry land during a storm event? a. Storm Surge b. Storm Flood c. Inundation d. Flood Setup 8. Hurricanes are a. Low Pressure Storms b. High Pressure Storms c. Storms that are only in the Pacific ocean d. Storms with slow wind speeds 9. What is the increase in the normal water elevation caused by a storm s wind and pressure? a. Storm Surge b. Storm Flood c. Inundation d. Flood Setup 10. Most deaths during hurricanes are caused by a. High winds b. Storm Surge c. Tornados d. Torrential Rain Northern Gulf Coastal Hazards Collaboratory Dauphin Island Sea Lab