The 2005 Hurricane Season had an influential role in highlighting the critical nature of vulnerability to hurricanes.
The world watched in horror as socially vulnerable groups struggled to cope with and recover from the effects of the hurricanes. The new challenge to emergency managers is to identify similar vulnerable populations in their areas before a hurricane strikes.
The aim of this project is to use geographic information systems (GIS) to identify vulnerable populations within the city of Tampa (a city that has not had a direct impact from a hurricane in over 80 years).
The 2004 and 2005 Hurricane seasons were record breaking seasons in terms of frequency and magnitude of hurricanes.
These seasons have also brought a renewed examination of the issue of social vulnerability compounding geophysical vulnerability.
Examples from Hurricanes Charley and
Katrina have displayed to the world how certain factors of social vulnerability, like poverty, race, homeowner status, family size, and age, can augment the effects of hurricanes for certain populations within affected cities. To properly identify vulnerable populations in the city of Tampa, Florida a review of the literature was conducted to determine a methodology.
The city of Tampa, Florida is a dense, urban city on the central Gulf Coast of the state of Florida.
The city is culturally and ethnically diverse and a center of commerce for the Tampa Bay area.
Tampa is situated along the coast of
Hillsborough County and accounts for nearly
30% of the county’s total population. The city of
Tampa and its 303,447 residents have enjoyed good fortune in dodging hurricanes for over eighty years.
Tampa has been threatened numerous times from hurricanes and tropical storms as 60 storms have come within 75 mi of the mouth of Tampa Bay in the last 100 years.
2000 U.S. Census Bureau Tracts of the City of Tampa, FL
The last hurricane to directly impact the Tampa
Bay area was the unnamed storm of 1921. In
October of 1921 the estimated category 3 storm made landfall just north of Tampa Bay, battered the city with winds exceeding 100 mph, and created a 10 to 12 ft storm surge in the Bay. The storm caused between one and ten million dollars worth of damage and was responsible for six deaths.
• 103 census tracts in the city of Tampa, FL
• 23 social vulnerability indicators
• Described both factors that increase social vulnerability, like renter-occupied housing units, race, age, and poverty status, and factors that decrease social vulnerability, like college education and income.
• Risk scores
• Unique for each indicator
• 4 classes
• Tracts with the highest concentration of an indicator received a score of 4 and tracts with the lowest concentration received a score of 1
• Total social vulnerability profile
• Summation of risk scores of all 23 indicators for all 103 census tracts
Tampa_2000_Clip
TotalSocVu
12 - 19 Lowest Vulnerability
20 - 28 Low Vulnerability
29 - 37 Medium Vulnerability
38 - 46 High Vulnerability
47 - 54 Highest Vulnerability
•Conduct a review of the vulnerability literature
•Identify an area of study
•Collect demographic and geographic data
•Research the area’s history with hurricanes
•Create a social vulnerability profile
•U.S. Census Bureau data describing indicators discovered in the literature review
•Create a physical vulnerability profile
•Overlay hazards maps onto the city map to determine geophysical vulnerability
•Create a total vulnerability profile
•Combination of the Social and Physical vulnerability profiles
This project is the result of continuing research first conducted with the USF Hurricane
Research Experience for Undergraduates (REU).
We would like to thank all those who were involved with the REU from the USF Honors
College and the REU faculty.
The total vulnerability profile was created through the summation of the social and physical vulnerability scores of each of the 103 census tracts.
The least vulnerable areas to hurricanes are the New
Tampa area and on the central peninsula. These are areas that have a very low occurrence of factors that increase social vulnerability (like poverty and low education).
The most vulnerable areas to hurricanes are located in downtown Tampa and
Ybor City.
These areas have high social vulnerability despite their moderate physical vulnerability.
Tampa_2000_Clip
TotalVuln
20 - 22 Lowest Vulnerability
23 - 38 Low Vulnerability
39 - 47 Medium Vulnerability
48 - 57 High Vulnerability
58 - 67 Highest Vulnerability
The physical vulnerability profile was created using hazard maps and overlay operations in the
ArcGIS software to spatially identify areas of physical vulnerability in the city of Tampa.
FEMA Q3 flood maps were used to find areas vulnerable to flood damage. Areas at greatest risk to flooding were given a score of 4 and least vulnerable areas were given a score of 1. A storm surge map was used to find vulnerability to storm surge in the city. Areas at risk of experiencing storm surge from a tropical storm were given the highest score of 5 and areas at no risk to storm surge were given a score of 0. A HAZUS Wind
Envelope map was used to identify areas at risk to high wind damage. Areas at highest risk were given a score of 4 and all others received a score of 3.
Storm Surge Map - Hillsborough County, FL FEMA Q3 Flood Map - Hillsborough County, FL HAZUS Wind Envelope Map - Hillsborough County, FL
Tampa_2000_Clip
TotalPhysV
8 - 9 Lowest Vulnerability
10 - 11 Low Vulnerability
12 - 13 Medium Vulnerability
14 - 15 High Vulnerability
16 - 17 Highest Vulnerability
Geographic Information Systems is a powerful tool for emergency managers. This simple tool can help managers identify areas of a community that are especially vulnerable to hurricanes.
This project highlights the importance of social vulnerability in assessing the total vulnerability of a community.
The social and total vulnerability profiles indicate the extreme vulnerability of areas like downtown
Tampa and Ybor City despite their moderate physical vulnerability.
These areas are economically important to the city of Tampa and deserve the full attention of emergency managers and policymakers to alleviate the areas’ extreme social vulnerability.