Student Activity
Tracking Hurricane Sandy
Science Inquiry Using GIS
Introduction
On October 22, 2012, Tropical Depression Eighteen formed in the Caribbean
Sea several hundreds of miles east of Nicaragua and north of Panama. Six
hours later it became Tropical Storm Sandy. Over the next ten days, Sandy
moved northward across the east ends of Jamaica and Cuba, along the
Bahamas, then turned northeastward to generally parallel the east coast of the
United States. Its sustained wind speeds increased to Hurricane Category 2
levels. The cyclone center consistently remained 200-400 miles offshore of the
U.S. until October 29. On that date, Sandy made a left turn, increased its
ground speed until it made landfall in New Jersey, then almost stalled about
100 miles inland. By this time, the storm strength was downgraded to
Hurricane Category 1. However, its cloud field covered all of the northeast
quadrant of continental United States and much of eastern Canada. Called a
"superstorm" by the news media, the extent of high winds, rainfall and snowfall
for several days were unusually wide. The dollar value of damage in the U.S.
alone is second only to that caused by Hurricane Katrina. Sandy's change in
direction was predicted by the National Weather Service. What did they see
that resulted in such a forecast?
In this lesson, you will map the path of a major tropical cyclone in the North
Atlantic using NOAA online access tools and ESRI's ArcGIS Online. Then, using
ImageJ software, you will analyze the storm viewed from space and apply these
methods to other storms to predict impact on human society.
Preparation
Attached here are several sets of information, directions, tutorials, and
worksheets to guide you through this investigation. Use only those sets
assigned by your teacher. Be sure to complete one or more of the Your Turn
activities listed at the end. Your teacher will give you further directions for
those when you reach that point.
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Student Activity
KWL Chart
What I Know
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What I Want to Know
Tracking Hurricane Sandy
What I Learned
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Student Activity
Expert Group 1: Data Miners
Accessing the National Hurricane Center Advisories
The National Hurricane Center (NHC) of the National Oceanic and Atmospheric
Administration (NOAA) issues advisories forecasting and reporting severe storm
conditions. The advisories are issued at least every six hours for the duration of
the storm and archived for historical reference. You will need to prepare a data
table like this one for recording the information you collect from the advisories.
NHC Advisory Data for Hurricane Katrina (2005)
Time
Wind Wind
Speed
UTC LAT LON
kts
mph Scale
kts
Adv
No
Date
19
28-Aug-05
0300
25.0
-86.2
100
115
Cat 3
6
Speed
mph
Press
mb
7
939
Explanation of Data Table Columns:
Adv No
Date
Time UTC
LAT
LON
Wind kts
Wind mph
Scale
Speed kts
Speed mph
Press mb
Advisory Number
Advisory issue date in dd-mmm format (eg. 26-Sep)
Universal Time Coordinate; time at the Prime Meridian in 2400 hour format
Latitude of cyclone center; record south latitudes as negative numbers
Longitude of cyclone center; record west longitudes as negative numbers
Sustained wind speed in nautical miles per hour (knots or kt)
Sustained wind speed converted to miles per hour (kt x 1.151)
Saffir-Simpson Scale category based on sustained wind speed
Ground speed of cyclone center in nautical miles per hours (knots or kt)
Ground speed converted to miles per hour (kt x 1.151)
Air pressure of cyclone center in millibars; standard sea level pressure=1013.25 mb
 Insure your computer is Internet-enabled. Launch your browser and point it to
http://www.nhc.noaa.gov.
 In the link panel on the left of the screen, find and click Past Advisories. In the row of
years at the top of the window, find and click 2005. In the Atlantic column, find and
click Hurricane Katrina.
 You are free to explore any of the advisories listed on this page. However, use only
the Forecast Advisories for data analysis in this lesson. Your teacher may also direct
you to limit your search to Advisory Nos. 19-29 only.
 Click an advisory link. Scan through the advisory noting the needed data on your NHC
Advisory Data for Hurricane Katrina (2005) chart. Click the browser's Back button. Then
repeat this step with the each succeeding advisory link until you have all of the
needed Katrina data from at least Advisory Nos. 19-29.
 When finished, ask your teacher to check your work before closing your browser. If
directed by your teacher, make another data table for NHC Advisory Data for Hurricane
Sandy (2012), using Advisory Nos. 1-31.
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Student Activity
Expert Group 2: Cartographers
Using ArcGIS Online
 Insure you computer is Internet-enabled. Double check that your teacher has copied
the Lesson_Data folder to your local hard drive. Launch your browser. Point it to
http://www.arcgis.com/.
ArcGIS Online (ArcGIS.com Map Viewer) is a online geographic information
system (GIS) provided free of charge by ESRI. With a GIS, you can create a map
in layers, display the layers as you choose, and determine how the layers of the
map interrelate. ArcGIS Online also provides a wide choice of base map types.
This allows you to display more kinds of information in more ways.
 Find and click the Map button at the top of the page. The ArcGIS.com Map Viewer is
displayed. For now, ignore (do NOT click) the buttons for Sign In, Try ArcGIS, and
Visit the Gallery.
 Find and click the Modify Map button at the top-right of the page. Notice the Add
button has appeared at the top-left of the page.
 A map of part of the world is displayed. Click the + in the upper-left corner of
the map to zoom-in. Click the - to zoom-out. Click the home icon (the house) to
return to the default view of the world. You can also zoom using the mouse
scroll wheel. You can click and hold the left mouse button and drag the map in the
window. Adjust the display until the eastern portion of North America and
some of the Atlantic Ocean nearly fills the display.
Now you will add data to the map for Hurricane Katrina (2005) and Hurricane
Sandy (2013) and adjust the color and size of the marker symbols to reflect the
scale of the storm at various times.
 Click the drop down arrow on the right side of the Add button.
Select Add Layer
from File. In the Add Layer from File dialogue, click Browse. Navigate to your
Lesson_Data folder and select Katrina-Data.csv. Click Open. Then click Import Layer.
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Student Activity
 Notice the Change Style panel on the left. Click the drop-down arrow to the right of the
field for  Choose an attribute to show. Select Category. For  Select a drawing style, click
the Options button.
 Click the marker symbol next to the label Category 5.
 In the Shape pop-up, select the round purple marker. Use the change arrows or the
slider to set the marker size to 60 px.
 Repeat the last step to set the other marker symbols according to this table:
Label
Category 5
Category 4
Category 3
Category 1
Tropical Storm
Size
60
50
40
20
15
Color
Purple
Red
Orange
Green
Blue
 Click OK at the bottom of the Change Style panel. Click Done.
 Click the drop-down arrow to the right of Katrina-Data in the Contents panel. Select
Show Table. The attribute table appears below the map. It should contain the same
data as the original CSV file.
 Each row of the attribute table contains the data for one marker symbol on the map –
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Student Activity
the same data that appears in the information box that pops-up when you click on a
marker symbol on the map. Click any row in the table. Notice that the corresponding
marker symbol on the map is highlighted in a cyan colored box. To select multiple
markers, Ctrl-click each additional marker to be highlighted.
 To clear the selection(s), click the drop-down arrow next to Table Options, and select
Clear Selection.
 Close the attribute table by clicking the X in the upper-right corner of the table.
 Stop here and check with your teacher. If time permits, click the Add button and
follow the above sequence of steps to add another feature layer to the map using
Sandy-Data.csv found in the Lesson_Data folder.
 Use the Change Style options to adjust the marker symbols for Hurricane Sandy
according the following table:
Label
Category 1
Tropical Storm
Category 2
Post Tropical Cyclone
Tropical Depression
Size
28
20
36
28
15
Color
Green
Blue
Yellow
Green
Black
 Click OK at the bottom of the Change Style panel. Click Done. Click the Home icon.
 Insure that both feature layers (Sandy-Data and Katrina-Data) are checked in the
table of contents.
If the feature layer is not visible on the map, it may be necessary to adjust the
visibility range. Setting the visibility range helps the marker symbols appear on
the map in an informative manner.
 Click the drop-down arrow next to the feature layer name Sandy-Data. Select Set Visibility
Range.
 The slider bar has two sliders. Drag the right slider all the way to the right.
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Student Activity
 Click the drop-down arrow next to the scale label below the left slider. From the list,
select Continent (1:50,000,000). Click anywhere on the map to close the visibility range
control.
 Repeat the last step for the Katrina-Data feature layer.
 In the table of contents, click each feature layer name once to display the legend for
that layer.
 Feel free to zoom in and out and reset the visibility range as needed.
Discuss and interpret the resulting map display. You should be able to note:
 The direction of each storm's center before and after making landfall
 The intensity of each storm - relate the marker color to the legend to interpret
wind speed; click a marker to display its data
 The ground speed of each storm - each marker is separated by about 6 hours.
So, greater spacing between markers indicates higher ground speed.
 What happens to ground speed and intensity when the storm makes landfall?
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Student Activity
Expert Group 3: Meteorologists
Comparing Hurricanes
 Insure you computer is Internet-enabled. Point your browser to this NOAA Web site:
http://www.nhc.noaa.gov/aboutsshws.php.
 Note wind speeds and characteristics of each level of the Saffir-Simpson Hurricane Winds
Scale. Keep this note for reference throughout the lesson.
 Point your browser to this NASA web site:
http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html.
Scroll down and begin reading at Nov. 9, 2012 Comparing the Winds of
Sandy and Katrina. Scan through this entire page making notes of the
following:
 The structure of Hurricane Sandy and the structure of Hurricane Katrina - how
were they alike? How were they different?
 What was different about the cloud fields of each storm?
 Hurricane Katrina followed a curved path over water and made landfall in
Louisiana. Hurricane Sandy followed a path paralleling the coastline but
suddenly turned left and made landfall in New Jersey. Sandy's path also
resulted in a cloud field so large it was called a "superstorm" by the news
media. This behavior was predicted by the National Weather Service. How can
you account for the differences in the behavior of these two storms?
 Damage from high winds, rain, and even flooding are usually expected in
hurricanes. Note the extent of precipitation from Sandy - especially rain and
snow. Comment on the extent of flooding caused by the storm.
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Student Activity
Expert Group 4: Analysts
ImageJ
 Insure you computer has ImageJ installed and the Lesson_Data folder contents are
accessible.
 Launch ImageJ.
 On the ImageJ menu bar, click File, select Open, navigate to your Lesson_Data folder,
and select Katrina-Landfall-050829.jpg. (The numbers in the file name represent the date
of the image: 2005-August-29.) The image opens in a separate window.
Preparing to Measure
You can easily measure distances and area in ImageJ, but first you must set
the measurement scale and select the image region to be measured. The image
you just opened has a latitude-longitude grid overlaid on it. You will measure
the distance along the 90˚W longitude line from 26˚N to 34˚N. Assuming the
Earth is a sphere and that longitude line is a 360˚ circle (the circumference of
the Earth), then this will be 8˚ of arc along that circle. Assume the
360˚circumference of the Earth is 25,000 miles. You will need to determine the
length of the 8˚ arc in miles. Do that now and record the value for later use.
Assume the Earth is a sphere and the
360˚ circumference is 25,000 miles.
How many miles long is this 8˚ arc?
 After you determine the length of the 8˚ arc, click the Line Tool
button on the
ImageJ button bar.
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Student Activity
 Place the cursor on the image exactly at the intersection of gird lines for 26˚N and 90˚W.
Click and hold the left mouse button and drag the cursor to the exact intersection of 34˚N
with 90˚W. Release the mouse button. You should see a yellow line drawn on the
image.
 On the ImageJ menu bar click Analyze and Clear Results.
 Again, click Analyze and select Set Measurements. Insure Area and Perimeter are checked
and all others are not checked. Click OK.
 Once again, click Analyze, then select Set Scale. In the Set Scale dialogue, change the
value in the Known distance field to the distance you calculated for the 8˚ arc length, and
change the Unit of length field to mile. Click OK.
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Enter here the value you
calculated for the length of an
8˚ arc of Earth circumference
 Click anywhere on the image once to delete the yellow line.
 On the menu bar, click Process, then Noise, and select Despeckle. This should breakup
the outline of the states so it does not interfere with thresholding.
 Click Image then Type and select 8-bit to change the image to an 8-bit gray scale
image.
 Click Image then Adjust and select Threshold. The image changes; the Threshold
dialogue is displayed.
Each pixel in the 8-bit gray scale image has a brightness value from 0 to 255.
White is 255 and black is 0. All values between are shown as a level of gray. In
ImageJ, thresholding is a tool that allows you to identify a specific range of
pixel values. All pixels in the image with these values are displayed in red while
all others remain unchanged. With thresholding, you can select specific
features and separate them from the background.
 A little experimentation might be necessary here. In the Threshold dialogue, move
the sliders until the main body of the cyclone cloud field is highlighted in red but not
the rest of the image.
 Click the Magic Wand button on the button bar. Then click inside the lower left portion
of the red area in the image. The red area should now be selected as indicated by a
yellow line around it.
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Student Activity
 Close the Threshold dialogue.
Now, for the actual measurements...
 Click Analyze and select Measure. The Results window opens showing the perimeter of
the selected area in miles and the area of the selection in square miles.
 Click the Line tool button and click the image once outside of the red area. Now use
the Line tool to draw a line across the red area in a place that seems to be an average
width of the storm cloud field.
 Again, click Analyze and measure. On line 2 in the Results window the approximate
average diameter (in miles) of the hurricane cloud field is shown in the Length
column. Try measuring the diameter in several different places. Record the average
diameter, perimeter, and area measures for later reference.
 In the Results window, click Results and select Clear Results without saving results.
Close the Results window.
 Close the image window without saving changes.
Measure Hurricane Sandy
Now you will use the same procedure to measure the approximate diameter,
perimeter, and area of Hurricane Sandy at landfall.
 On the ImageJ menu bar, click File, select Open, navigate to the Lesson_Data folder,
and select Sandy-Landfall-121029-2115.jpg. (The numbers in the file name represent
date and time of the image: 2012-October-29 at 2115 UTC.) Click Open.
 Use an atlas, Google Earth, ArcGIS Online, or other map source to correctly identify
the locations of Corpus Christi, Texas and St. Petersburg, Florida. Draw a line between
them on the image and use it to set the measurement scale. The distance is 900 miles.
 Perform the thresholding procedure and then measure and record approximate
diameter, perimeter, and area of Hurricane Sandy's cloud field showing in this image.
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Student Activity
 After your teacher checks your work, close ImageJ (that will close all ImageJ
windows) without saving.
Analyze, Interpret, Apply
Using ArcGIS Online
Hurricanes are North Atlantic cyclones that form over warm ocean water.
Damage from wind and storm surge, heavy rains, and sometimes flooding can
occur along the coast and in most other areas that are under the swirling cloud
field of the cyclone. When the center of the cyclone over land, it is called
"landfall."
Just before 1500Z on August 29, 2005, Hurricane Katrina made landfall in
New Orleans, Louisiana. At that time it was a Category 3 hurricane with
sustained winds of 126 mph. The center of the storm was moving north at a
speed of 16 mph. The storm caused $148.8 billion worth of damage (in 2013
dollars) and 1833 deaths.
In October, 2012, Hurricane Sandy was moving up the east coast of the United
States. It was maintaining a Category 2 status with sustained winds of 103
mph. Although correctly predicted by the National Weather Service, what
happened next was unusual. On October 29, the storm turned toward land and
increased its ground speed to an average of more than 25 mph for the next 12
hours. It made landfall in New Jersey at about 2230Z. It caused $65.8 billion
in damage and 159 deaths.
Hurricanes Sandy and Katrina are the two most destructive hurricanes to land
in the United States since such records began in 1980.
Once the storm center is over land, the cyclone begins to lose energy.
Hurricane Katrina rapidly downgraded to Category 1, then Tropical Storm, and
finally lesser status within about 18 hours of landfall. However, Hurricane
Sandy did something else that caused the news media to call it a "superstorm."
And it continued for several more days!
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Student Activity
What happened to Hurricane Sandy? What conditions developed that could
cause this unusual behavior? What did the forecasters in the National
Hurricane Center and the National Weather Service see that allowed them to
predict what happened?
Discuss these questions with your team members. Review the information
supplied by each of your team's experts. If needed, you can review much of the
information using a special map prepared for you on ArcGIS Online.
 Launch your browser and point it to this URL: http://bit.ly/1tkevgO.
Here you will find ArcGIS Online with many layers already loaded, configured
and ready for display. You are free to manipulate the feature layers anyway you
feel will help with the investigation.
 You can...
 Zoom in and out; zoom to rectangle
 Turn feature layers on and off
 Click a marker to display its attributes
 Search for places
 Compare similar features of different storms - such as the path of Hurricane
Sandy compared to the path of Hurricane Katrina
 Compare different features of the same storm - such as the sustained wind speed
of Sandy compared to Sandy's central air pressure
 Measure distance and area
Your team's expert Cartographer has a some experience with this ArcGIS.com
Map Viewer and can help get the team started.
 To measure distance, click the Measurement Tool
button.
 The Find area, length, or location dialogue appears with the
area button depressed by default. Click the Length button;
the default unit of length is miles. Click once at the
starting point of the measurement; click once again at
the ending point or at a vertex where the measured line
changes direction; double-click to end the measurement.
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Read the measured distance under Measurement Result in the dialogue.
 Click the Clear Measurement button to delete the measurement line from the map.
 Click the Area Measure
button and repeat the process in the last 2 steps to
measure an area.
 When you feel you understand what happened to Hurricane Sandy sufficiently well to
report to the class, check with your teacher, then close your browser without saving.
YOUR TURN
Select and complete one or more of the activities below. Then create and deliver a report of the
results. The report must be in a format you have discussed and agreed upon with your teacher.
It could be audio-visual in form using presentation software such as PowerPoint; it could be in
printed format such as a poster presentation; or it could be in written or oral form similar to a
letter, a printed report, or a oral report to the class. In each case, drawing or other artwork or
graphics should be included to clarify explanations.
Research and collect photographs of damage caused by Hurricane Sandy. Relate each to
an image of the cloud cover from that day as seen in a GOES satellite image. Discuss the
effect of the storm on the human population of the affected areas. Suggest and describe
several options for lessening the impact of such severe storms on society.
Investigate the forecasted and actual rainfall, snowfall, and flooding resulting from Hurricane
Sandy. We expect every tropical cyclone to bring high winds, heavy rain, and, sometimes,
floods. What was unusual about Hurricane Sandy? How did interactions between winds,
landforms, ocean temperatures and currents affect the storm's behavior?
Devise a plan to determine the diameter, perimeter, and area of the cloud field and the
intensity of other major hurricanes when they made landfall in the United States. Is there a
definite relationship between the size of the cloud field at landfall and the amount of damage
caused by the storm? Is this at all related to sea surface temperature and/or land
topography? If so, how?
Develop and use a model to describe how hurricanes form and how that formation process
is related to sea surface temperature. In your discussion, emphasize the unique properties
of water that contribute to storm development. Use the model to indicate the flow of energy
into and out of the storm system. Do hurricanes have the same intensity over land that they
do over water? Explain. Why does the National Weather Service call the period from June 1
to November 30 "hurricane season?"
Research major hurricanes making landfall in the United States since 1980. Gather the data
in a comma-delimited text file with columns for Hurricane Name, Landfall Date, Latitude,
Longitude. Add these data to the Tracking Hurricane Sandy map in ArcGIS Online. Which
geographic areas are most likely to experience a major hurricane this year? What specific
conditions are necessary for such a severe storm to develop? Make a prediction about the
occurrence of a future hurricane based on the evidence you have gathered so far. Defend
your prediction.
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Student Activity
Re-examine your KWL chart. Do any questions remain unanswered? Select a question and
devise a plan to investigate a possible answer or design a possible solution. Discuss your
plan with your teacher and have it approved before starting work.
Using the data from the Hurricane Sandy advisories, create a X-Y line graph with central air
pressure over time on one line, sustained wind speed on another line, and ground speed on
a third line. Compare and contrast the results to develop a position on the relationship
between these three storm characteristics. Do the same for Hurricane Katrina. Are you led
to the same conclusion by the graphs for both hurricanes? What societal conditions
contributed to the overall damage total for each storm? Defend your position in your report.
Sea Surface Temperature
This image map shows sea surface temperature. The data are averaged for the month
of October 2012. The data were collected by the MODIS (Moderate Resolution Imaging
Spectroradiometer) sensor carried on NASA's Aqua satellite. The color-coded legend
matches the map colors to Celsius temperature. Use this image for reference when
studying the Tracking Hurricane Sandy map in ArcGIS Online.
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