Transcript USF Weather Center - University of South Florida

Identifying Vulnerable Populations to Hurricanes in the city of Tampa, Florida
Dr. Jennifer Collins and Dustin Hinkel
Department of Geography, The University of South Florida
ABSTRACT
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).
INTRODUCTION
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.
STUDY AREA
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
SOCIAL VULNERABILITY PROFILE
• 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
PHYSICAL VULNERABILITY
PROFILE
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
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.
FEMA Q3 Flood Map - Hillsborough County, FL
HAZUS Wind Envelope Map - Hillsborough County, FL
Tampa_2000_Clip
TotalSocVu
12 - 19 Lowest Vulnerability
20 - 28 Low Vulnerability
29 - 37 Medium Vulnerability
38 - 46 High Vulnerability
47 - 54 Highest Vulnerability
TOTAL VULNERABILITY PROFILE
Tampa_2000_Clip
TotalPhysV
8 - 9 Lowest Vulnerability
METHODOLOGY
•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
Acknowledgements
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
10 - 11 Low Vulnerability
12 - 13 Medium Vulnerability
14 - 15 High Vulnerability
16 - 17 Highest Vulnerability
CONCLUSION
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.