Unit 3 Hurricane Hazards - Brands · PDF fileUsing your Web browser, open the University of Illinois World Weather Project Hurricane Web page ( Hurricane Damage). ww2010.atmos.uiuc.edu/(Gh)

In this unit, you will answer these questions • What makes a hurricane deadly?

• Which places in the U.S. are the most hurricane-prone?

• How are hazards different from risks?

• How do you determine the likelihood of a hurricane strike in coastal areas?

• How do hurricanes cause death and destruction?

• Who is most at risk from hurricanes in the U.S.?

Unit 3

Hurricane Hazards

The New England Hurricane of 1938 devastated the Harbor View district, southeast of New Bedford, Massachusetts. A storm-shocked husband and wife survey the remains of their home and community. This storm traveled 600 miles (966 km) in 12 hours, surprising southern New England and causing widespread destruction.

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Data Detectives: Tropical Cyclones Unit 3 – Hurricane Hazards

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Sources of hurricane riskWarm-up 3.1

Th ink for a moment about the dangers that tropical cyclones pose to humans. Certainly a cyclone’s high winds are one serious hazard to human life and property, but there are others as well.

Familiar and unfamiliar hazardsIn this activity, you will research hazards associated with tropical cyclones. Many of these hazards will be familiar, but some of them may surprise you. Using your Web browser, open the University of Illinois World Weather Project Hurricane Web page ( Hurricane Damage).

ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/hurr/damg/home.rxml

Follow the links in the center of the page to examine each of the hazards associated with tropical cyclones, and then answer the following questions.

1. On which side of a tropical cyclone are wind speeds the highest? (Hint: Watch the videos associated with these Web pages.)

2. Identify the three factors that contribute to a tropical cyclone’s storm surge.

3. Which is greater in a tropical cyclone — the risk to people from fl ooding due to the heavy rainfall, or the danger posed by severe winds?

Additional hurricanehazard informationAnother Web site with excellent information about hurricane hazards is sponsored by NOAA( Hurricane Hazards).

hurricanes.noaa.gov/prepare/title_hazards.htm

If any of these Web sites is no longer available, visit the SAGUARO Project Web site for a list of updated addresses( SAGUARO Project).

www.scieds.com/saguaro

Accessing Web pages through the Media ViewerIf you have the cyclones.apr project fi le open in ArcView, you can click the Media Viewerbutton and open the indicated Web pages from the media list.

Sources of hurricane risk 55


4. What makes the tornadoes associated with tropical cyclones so dangerous?

5. Which aspect of tropical cyclones is a particular hazard to swimmers both before and aft er the tropical cyclone occurs?

56 Sources of hurricane risk


Hurricanes cause an average of almost 5 billion dollars damage per year to the U.S. mainland. No matter where you live, you pay some of these costs in the form of higher taxes and insurance. Th is investigation will look at hurricane risk in the U.S., fi rst focusing on the nation’s 10 most destructive hurricanes and then looking at general risk data for the entire eastern seaboard.

Traits of deadly hurricanesWhat do the deadliest hurricanes have in common? To explore this question, you will look at a map of these devastating storms and search for meaningful patterns.

Launch ArcView, locate and open the cyclones.apr fi le, and open the Top 10 U.S. Hurricanes view.

Th is view shows the tracks of the 10 most damaging hurricanes (in terms of monetary losses) between 1900 and 2005. Th e thickness of the lines represents the relative destructiveness of each hurricane. However, even thin lines show hurricanes that were extremely destructive.

1. Look at the top 10 hurricane tracks. What similarities do you see in where they formed, and the general shapes of their paths?

Track lengthFirst, you will determine the average track length of these hurricanes.

Activate the Top 10 Tracks theme.

Click the Statistics button .

Calculate statistics for all features of the Top 10 Tracks theme, using the Path Length (km) fi eld.

Select the Basic output option and click OK.

The top 10 U.S. hurricanesInvestigation 3.2

To activate a theme, click its name in the Table of Contents.

The top 10 U.S. hurricanes 57


Th e average path length of the top 10 most destructive hurricanes is reported in the Statistics window as the Mean.

2. What is the average path length (in km) for the top 10 destructive Atlantic hurricanes?

Close the Statistics window.

Next, you will compare the average path length of the top 10 most destructive Atlantic hurricanes to that of all Atlantic hurricanes between 1950 and 2005.

Turn on the Atlantic Hurricanes theme.

Activate the Atlantic Hurricanes theme.


Calculate statistics for all features of the Atlantic Hurricanes theme, using the Path Length (km) fi eld.


Th e average path length of all Atlantic hurricanes is reported in the Statistics window as the Mean.

3. What is the average path length (in km) for all Atlantic hurricanes?


Path length and intensityTo examine the relationship between length and intensity in greater detail, you will create a summary table of these two characteristics.

Click the Summarize button .

In the Summary Table Defi nition window, select the Atlantic Hurricanes theme and the Category fi eld.

Choose Path Length (km) from the Field drop-down menu and Average from the Summarize By drop-down menu, then click Add.

Select the All Values option and click OK. (See sidebar if you receive an error message.)

To turn a theme on or off , click its checkbox in the Table of Contents.

Summary tablewon’t open?If you receive an error message when you create the summary table, you can open the table by closing the Top 10 U.S. Hurricanes view, and clicking on Tables in the list of icons on the left side of the screen. Select the Summarize Atlantic Hurricanes by Category in the list below and click Open. Remember to go back to the Powering Tropical Cyclones view to continue the investigation.

58 The top 10 U.S. hurricanes


In the summary table, the Path Length (km)_Avg fi eld gives the average path length in km for each category of hurricane.

4. Describe any relationships you see between the length of a hurricane’s path and its intensity.

Close the summary table.

Turn off the Atlantic Hurricanes theme.

Creating a simple hazard mapA simple way to describe hurricane hazard is to count the number of hurricanes that have made landfall in a particular area. You will create a simple hurricane hazard map of the U.S. using landfall information from 1950 – 2005.

Click the Media Viewer button and open the U.S. Hurricane Strikes image.

5. Count the number of hurricane landfalls for each state, and record that number in the appropriate state on Map 1. Create a hurricane hazard map by classifying the states into three hazard levels and coloring each state on the map according to its hazard level:

High = 10 or more storms making landfall.

Moderate = 5 to 9 storms making landfall.

Low = 0 to 4 storms making landfall.

Map 1 — Hurricane hazard map

Close the Media Viewer window.

Directions for hazard mapAssign a risk factor based on the number of times a hurricane has crossed a state’s boundaries. Assign colors or patterns to each hazard level, and color or shade the map and legend accordingly.

What is the differencebetween hazards and risks?The terms hazard and risk are sometimes used interchangeably, but they have distinct meanings. A hazard is a condition or event that is capable of causing damage or harm.

On the other hand, risk is the probability that a hazard will cause harm. Risk is usually stated as a frequency or percentage of probability that some event will occur over some period of time and for a specifi ed area or location.

For example, the risk of storm surge for a coastal city might be stated as something like “a 3 percent chance per year of experiencing a storm surge higher than 4 meters.”

What is the “H” in H4?In the North Atlantic, tropical cyclones are called hurricanes, so “H” stands for Hurricane. Here, it means the same thing as category.



Hurricane destruction over timeTh e destruction caused by a hurricane is usually defi ned in terms of its eff ect on human populations. Next, you will look for changes in the destructive nature of hurricanes over time, as coastal areas have developed and grown.


Click the Open Th eme Table button .

6. Use the information in the theme table to complete Table 1. Round the damage fi gures to the nearest billion dollars.

Table 1 — Top 10 hurricane extremes

Field Name of hurricane Damage 2005 dollars

Deaths Year

Highest dollar damage

Highest death toll

Most recent

Next, you will sort hurricanes based on the number of deaths they caused.

Click the Deaths fi eld header in the table and click the Sort Descending button .

Look at the relationship between the number of people killed in each storm [Deaths], and the hurricane’s date [Year]. Th e greatest number of casualties occurred in the Galveston hurricane of 1900, whereas the fewest occurred with Hurricane Andrew in 1992. In general, the number of deaths from major hurricanes is declining.

7. Why do you think the number of deaths from major hurricanes is declining, even though the population of coastal areas is growing?

8. What is the exception to the pattern of fewer deaths in more recent hurricanes? Speculate as to why casualties may have been high for this particular storm.

Close the theme table.

No deaths in ‘44?There is no reliable casualty fi gure for the 1944 hurricane, so it is listed as 0.

Damage AmountsAll dollar amounts have been adjusted to the value of the U.S. dollar in 2005, for purposes of comparison.

To activate a table fi eld, scroll across and click on its name. Active table fi elds are highlighted gray.



Florida — where Hurricanes call “home”Let us take a closer look at Florida, the state that has been most adversely aff ected by hurricanes this past century.

Click the QuickLoad button , select the Florida extent, and click OK.

Although Florida’s nickname is the Sunshine State, it is no wonder that the University of Miami sports teams are called the Hurricanes. Florida was hit hard by some of the most powerful storms of the 20th century. Next, you will determine which of the top 10 hurricanes crossed Florida. First, you must use a query to highlight Florida.

Click the Query button .

To select the state of Florida, query the States theme for ([State name] = “Florida”) as shown in steps 1 – 6:

If you have diffi culty entering the query statement correctly, refer to the Quickload Query described at left .

Close the Query Builder window.

Next, you will use a Select By Th eme operation to highlight the top 10 hurricanes that crossed Florida.

Click the Select By Themebutton .

In the Select By Th eme window, select the features from the Top 10 Tracks theme that intersect the highlighted features of the States theme.

Click the New button, but do not close the Select By Theme window.

QuickLoad Query • Click the QuickLoad Query

button, select the State of Florida query.

• Click OK.

• Click New.

Read query statement here as you enter it.

2) Double-click Field

3) Single-click Operator

4) Double-click or type Value

5) Choose Display Mode 6) Click New

1) Select Theme



On the map, the tracks of the top 10 hurricanes that crossed Florida will be highlighted. Th e number of tracks crossing Florida is displayed as the Number of features selected at the bottom of the Select By Th eme window.

9. How many of the top 10 hurricane tracks cross Florida?

To fi nd the extent of the destruction Florida suff ered from these hurricanes, you will fi rst calculate the total damage caused by the hurricanes that made landfall in Florida.

In the Select By Th eme window, click the Statistics button .

In the Statistics window, calculate statistics for the selected features of the Top 10 Tracks theme, using the Damage (2005 dollars) fi eld.

Choose the Basic output option and click OK.

Th e monetary damage resulting from the top 10 most destructive hurricanes is reported in the Statistics window as the Total.

10. What was the total damage from these hurricanes in 2005 dollars?

About 90 percent of this damage occurred where the storms fi rst made landfall — in this case, in Florida.

11. What was Florida’s share of the total damages from these storms? (In other words, what is 90 percent of the total you found in the previous question?)


Repeat this process to fi nd the total number of deaths from these hurricanes, using the Deaths fi eld.

Th e number of deaths resulting from the top 10 most destructive hurricanes is reported in the Statistics window as the Total.

12. How many people died as a result of these hurricanes?

13. Who do you think pays for these damages? How?


Click the Clear Selected Features button .



Florida’s summer of 2004Even by Florida’s standards, the summer and early fall of 2004 was one, long nightmare as a result of four powerful hurricanes that blasted the state during August and September. Individually, none of the hurricanes making landfall in Florida in 2004 ranked among the “top 10” in terms of monetary damages. However, collectively they were devastating, both economically and psychologically. Hurricanes Charley, Frances, Jeanne, and Ivan all caused tremendous amounts of damage to the entire Florida peninsula, aff ecting everything from cities to agricultural crops.

Turn off the Top 10 Tracks theme.

Turn on the 2004 Florida Hurricanes theme.

Activate the 2004 Florida Hurricanes theme.

Th is theme shows the tracks of the four 2004 hurricanes that impacted the state of Florida.

Using the Identify tool , click on each of the four storm tracks. Use the information provided in the Identify Results window to complete Table 2.

Table 2 — 2004 Florida hurricane statistics

Name Landfall location

Category Damage 2005 dollars

Deaths

Charley

Frances

Jeanne

Ivan

Close the Identify Results window.

14. Using the map on your screen and information from Table 2, determine which of the four 2004 Florida hurricanes made landfall outside of Florida. Why would communities in Florida have been aff ected by this storm?


Calculate statistics for all features of the 2004 Florida Hurricanes theme, using the Damage (2005 dollars) fi eld.


Th e total monetary damages for Florida resulting from the 2004

Damage AmountsAll dollar amounts have been adjusted to the value of the U.S. dollar in 2005, for purposes of comparison.



hurricanes is reported in the Statistics window as the Total.

15. What were the total monetary damages resulting from the 2004 Florida hurricanes?



Click the Open Th eme Table button .

Examine the Damage Rank and Damage (2005 dollars) fi elds.

16. How would the four 2004 Florida hurricanes rank, in terms of damages, if they had been a single event?

Close the theme table.

Quit ArcView and do not save changes.



Exploring hurricane hazardsReading 3.3

Coastal populationsPeople have long depended on the sea as a source of food, as a moderating infl uence on climate, and as a means of trade and travel. However, what is one day a calm ocean can the next day produce storms of destruction.

Historical impacts of hurricanesHistorical researchers estimate that Atlantic hurricanes were responsible for up to half a million deaths between 1492 and 2005. Th is estimate includes both coastal and off shore losses.

Th e total number of ship-related casualties associated with Atlantic tropical cyclones is unknown, but there are clues. Some perspective on the magnitude of ship losses worldwide is gained by realizing that on the coast of England alone there have been a minimum of 250,000 wrecks! (From Cameron, A., and R. Farndon. 1984. Scenes from sea and city: Lloyd’s List 1734-1984. Lloyd’s of London Press, London.)

In fact, to 1825, more than fi ve percent of the vessels in the [West] Indies navigation were lost due to shipwrecks; the biggest part due to bad weather. (From Marx, R. F. 1981. Shipwrecks in Mexican waters. Pablo Bush Romero and Club de Exploraciones y Deportes Acuaticos de Mexico.)

Retrieved from www.nhc.noaa.gov/pastdeadlytx3.html

Coastal population growthAmericans love the beach, and are living near the coasts in increasing numbers. According to a NOAA report, 54 percent of the U.S. population lives in coastal counties. Nearly 60 percent of those people live on the Atlantic and Gulf Coasts, putting them at risk from hurricanes.

Figure 1. Atlantic Coast and Gulf Coast population growth from 1960 – 2000.

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Declined – stableStable – doubled (200%)200 – 300% growth300 – 400% growth400 – 500% growth500 – 1300% growth

Population change1960 – 2000

Exploring hurricane hazards 65


Coastal populations have increased dramatically since 1960, particularly in Florida, the Carolinas, and Virginia (Figure 1 on the previous page). Th e more people that live near the ocean, the greater the chances that they will someday be in the path of a hurricane.

A full report on coastal population growth is available at

oceanservice.noaa.gov/programs/mb/supp_cstl_population.html

A news story about the coastal population growth report is also available at

www.magazine.noaa.gov/stories/mag167.htm

1. Do you think ships are more vulnerable or less vulnerable to hurricanes today than they were 100 years ago? Explain.

2. Why do you think the population of coastal areas is growing, despite the obvious risk of hurricanes?

Types of hazardsTh e hazards associated with hurricanes extend beyond the dangerous high winds that accompany hurricanes as they come ashore. Th e storm surge and large amounts of rain associated with hurricanes can cause substantial inland fl ooding in low-lying areas as well as landslides and mudfl ows in hilly regions.

Storm surge — Galveston Island (1900) On September 8, 1900 the greatest natural disaster to ever

strike the United States occurred at Galveston, Texas. In the early evening hours of September 8, a hurricane came ashore at Galveston bringing with it a great storm surge that inundated most of Galveston Island and the city of Galveston. As a result, much of the city was destroyed and at least 6000 people were killed in a few hours time.

From Monthly Weather Review (September 1900). Retrieved from

www.history.noaa.gov/stories_tales/cline2.html

Th e storm surge crested at around 5 m (17 ft ), completely submerging the island, where the highest elevation at the time was 2 m (9 ft ).

66 Exploring hurricane hazards


Landslides and mudfl ows — Hurricane Mitch (1998) In an awesome display of power and destruction, Hurricane Mitch

will be remembered as the most deadly hurricane to strike the Western Hemisphere in the last two centuries! ... Th e death toll currently is reported as 11,000 with thousands of others missing. Th ough the fi nal death toll will never be known, it is quite likely that Mitch directly killed more people than any Atlantic hurricane in over 200 years.

Although the ferocity of the winds decreased during the westward drift , the storm produced enormous amounts of precipitation caused in part by the mountains of Central America. As Mitch’s feeder bands swirled into its center from both the Caribbean and the Pacifi c Ocean to its south, the stage was set for a disaster of epic proportions. [Th e storm’s movement slowed over the volcanic peaks of Central America, and] rain fell at the rate of a foot or two per day [in some areas]. Total rainfall [for the storm was] as high as 75 inches [about two meters]. Th e resulting fl oods and mud slides virtually destroyed the entire infrastructure of Honduras and devastated parts of Nicaragua, Guatemala, Belize, and El Salvador [Figure 2]. Whole villages and their inhabitants were swept away in the torrents of fl oodwaters and deep mud that came rushing down the mountainsides. Hundreds of thousands of homes were destroyed.

Retrieved from lwf.ncdc.noaa.gov/oa/reports/mitch/mitch.html

Wind damage — Hurricane Andrew (1992) Andrew was a small and ferocious Cape Verde hurricane that

wrought unprecedented economic devastation along a path through the northwestern Bahamas, the southern Florida

Figure 2. Mudflow debris from Hurricane Mitch washed out this bridge in the town of Choluteca, Honduras.

Figure 3. Damage from Hurricane Andrew depended on the quality and type of construction used. In many neighborhoods, like Lakes by the Bay, few structures escaped undamaged.

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Feeder bands — also known as rain bands. The lines or bands of thunderstorms that spiral into and around the center of a tropical system. They occur in advance of the main area of rain that precedes the eye and are usually 40 – 80 mi (64 – 129 km) apart.



peninsula, and south-central Louisiana. Damage in the United States is estimated to be near $50 billion, making Andrew one of the most expensive natural disasters in U.S. history.

[Andrew] struck southern Dade County, Florida especially hard, with violent winds and storm surges characteristic of a category 4 hurricane... and with a central pressure (922 mb) that is the third lowest this century for a hurricane at landfall in the United States. In Dade County alone, the forces of Andrew resulted in 15 deaths and up to one-quarter million people left temporarily homeless [Figure 3 on previous page]. An additional 25 lives were lost in Dade County from the indirect eff ects of Andrew. Th e direct loss of life seems remarkably low considering the destruction caused by this hurricane.

Retrieved from www.publicaff airs.noaa.gov/andrew92.html

Inland fl ooding — Hurricane Floyd (1999) Floyd brought fl ooding rains, high winds, and rough seas along

a good portion of the Atlantic seaboard from the 14th through the 18th of September. Th e greatest damage occurred along a path from the eastern Carolinas northeast into New Jersey and [extending to the coast of] Maine. Several states had numerous counties declared disaster areas. Flooding caused major problems across the region, and at least 77 deaths have been reported. Damages are estimated to be $1.6 billion in Pitt County, North Carolina alone, and total storm damages may surpass the $6 billion caused by Hurricane Fran in 1996. Although Hurricane Floyd reached category 4 intensity in the Bahamas, it weakened to category 2 intensity at landfall in North Carolina. Floyd’s large size was a greater problem than its winds, as the heavy rainfall covered a larger area and lasted longer than with a typical category 2 hurricane. Approximately 2.6 million people evacuated their homes in Florida, Georgia, and the Carolinas — the largest peacetime evacuation in U.S. history. Ten states were declared

major disaster areas as a result of Floyd, including Connecticut, Delaware, Florida, Maryland, New Jersey, New York, North Carolina, Pennsylvania, South Carolina, and Virginia. Th ere were several reports from the Bahamas area and northward of wave heights exceeding 50 feet [15 meters]. Th e maximum storm surge was estimated to be 10.3 feet [3.75 meters] on Masonborough Island in New Hanover County, NC [Figure 4].

A summary of Floyd’s impact on North Carolina:

• 51 deaths.

• 7000 homes destroyed.

• 17,000 homes uninhabitable.Figure 4. View of flooding along Main Street in Tarboro, North Carolina from Hurricane Floyd.

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• 56,000 homes damaged.

• Most roads east of I-95 fl ooded.

• Tar River crested 24 ft [7.3 m] above fl ood stage [Figure 4].

• Over 1500 people rescued from fl ooded areas.

• Over 500,000 customers without electricity.

• 10,000 people housed in temporary shelters.

• Much of Duplin and Greene Counties under water.

• Severe agricultural damage throughout eastern North Carolina.

• Wilmington reported a 24-hour rainfall record of 13.38 in [34 cm], a 128-year record, and a total of over 19 in [48 cm] for the event.

“Nothing since the Civil War has been as destructive to families here,” says H. David Bruton, the state’s Secretary of Health and Human Services. “Th e recovery process will be much longer than the water-going-down process.”

Retrieved from lwf.ncdc.noaa.gov/oa/climate/extremes/1999/september/extremes0999.html

3. What are two ways that tropical cyclones can produce severe fl ooding?

4. Describe two factors that can signifi cantly increase the rainfall from a tropical cyclone.



5. List and explain several factors that helped make Hurricane Mitch “the most deadly hurricane to strike the Western Hemisphere in the last two centuries.”



What are the chances?A probability of 0.20 means that there’s a 20 percent chance that a hurricane will strike in any one year. Over ten years, on average, the area can expect 2 hurricanes.

Th e devastating eff ects of hurricanes are controlled by several factors. Clearly, destruction is greater when hurricanes strike cities than when they encounter unpopulated areas.

Launch ArcView, locate and open the cyclones.apr fi le, and open the Top 10 U.S. Hurricanes view.

Turn off the Top 10 Tracks theme.

Click the QuickLoad button , select the Atlantic & Gulf Coasts extent, and click OK.

Turn on the Hurricane Landfall Probability theme.

Th e Hurricane Landfall Probability theme shows the likelihood that a hurricane will strike a particular area in any given year. Most states along the Atlantic and Gulf Coasts have some annual risk for a hurricane strike.

1. What is the range of annual hurricane landfall probability experienced by the states along the Atlantic and Gulf Coasts? (Turn off the Major Metropolitan Areas theme for a clearer view.)

Th e Major Metropolitan Areas theme shows six selected areas along the Atlantic and Gulf Coasts that have large populations. Next, you will determine the number of people at risk of a hurricane strike in these areas.

Complete the Table 1 by activating the indicated theme and using the Identify tool to click on each of the metropolitan areas.

2. Use the Landfall probability (%) fi gures to rank the areas according to their annual hurricane risk (1 = greatest risk, 5 = least risk), and record the rankings in Table 1.

Table 1 — Hurricane risk ranking of major U.S. metropolitan areas

Metropolitan area

2004 Area population(Activate the Major Metropolitan Areas theme)

Round to the nearest 100,000

Landfall probability (%)

(Activate Hurricane Landfall Probability theme)

Risk ranking

Boston

Houston

Miami

New Orleans

New York

Washington, D.C.

Investigation 3.4 Risk to coastal communities

WarningClick directly on the star symbol for each metropolitan area with the Identify tool when you are fi nding the risk probability.

To turn a theme on or off , click its checkbox in the Table of Contents.

To activate a theme, click its name in the Table of Contents.

Risk to coastal communities 71


3. Using the information in the table, estimate how many hurricanes the Washington, D.C. area is likely to experience in an average decade. (See sidebar for hint.)

Close the Identify Results window.

How many people are at risk?You have looked at the risk in major metropolitan areas, but a signifi cant part of the U.S. population lives outside these areas. You will complete this investigation by fi nding the total population of all counties with any level of hurricane risk.

Click the Select By Th eme button .

Select the features from the U.S. Counties theme that intersect all the features of the Hurricane Landfall Probability theme.

Click the New button but do not close the Select By Th eme window.

Click the Statistics button in the Select By Th eme

window.

Calculate statistics for the selected features of the U.S. Counties theme, using the 2005 Population fi eld.

Choose the Basic statistics option and click OK.

What are the chances?A probability of 0.20 means that there’s a 20 percent chance that a hurricane will strike in any one year. Over 10 years, on average, the area can expect 2 hurricanes.

72 Risk to coastal communities


Th e number of people at risk from hurricanes is reported as the Total in the Statistics window.

4. How many counties (Number of Features) in the U.S. face some risk from hurricanes?

5. What is the total 2005 population (Total) of the counties at risk from hurricanes?



Calculate statistics for all features of the U.S. Counties theme, using the 2005 Population fi eld.

Choose the Basic statistics option and click OK.

Th is number of people living in the contiguous 48 states is reported as the Total in the Statistics window.

6. What is the total 2005 population of the contiguous 48 states?

7. What percentage of the population of the contiguous 48 states is at risk from hurricanes?

8. Describe the measures that you would take to minimize the risk to this population.

Close the Statistics and Select By Th eme window.

Quit ArcView and do not save changes.

Contiguous 48 states — all of the states that physically contact one another; in other words, all of the states except Alaska and Hawaii.

Risk to coastal communities 73


74 Risk to coastal communities


Documents

Unit 3 Hurricane Hazards - Brands · PDF fileUsing your Web browser, open the University of Illinois World Weather Project Hurricane Web page ( Hurricane Damage). ww2010.atmos.uiuc.edu/(Gh)