The Impact of Climate Change on Hurricane Flooding Inundation and

Economic Damages

Ashley Frey

Dr. Francisco Olivera, Dr. Jennifer Irish, Mir Emad Mousavi, Dr. Billy Edge, Dr. James Kaihatu, Katy Song, Lauren Dunkin, and Sean Finn

November 12, 2008Gulf Coast Hurricane Conference

Sponsored by the National Commission on Energy Policy

http://visibleearth.nasa.gov/view_rec.php?id=7957

Outline• Introduction to Hurricane Flooding

• Objectives of Research

• Site Location and Selection of

Hurricanes

• Climate Projections

• Methodology

• Results and Discussion• Flooding Inundation• Property Damages

• Conclusions

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Hurricane Flooding

2005 Hurricane Season

• Most Tropical Storms – 27• Most Hurricanes – 15• Most Intense Hurricane –

Wilma (882 mb)• Cost – $50 Billion

http://www.theage.com.au/ftimages/2005/08/30/1125302540219.html

http://www.theage.com.au/ftimages/2005/08/30/1125302540219.html

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Objectives of Research• Determine flood levels based on wind-surge, wave setup, subsidence,

eustatic sea level rise, and astronomical tides

• Calculate the area of flooding inundation

• Estimate the cost of property damages

• Compare results between hurricane scenarios

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Site Location – Corpus Christi, TX

http://www.theage.com.au/ftimages/2005/08/30/1125302540219.html

http://maps.google.com 5

Site Location – Corpus Christi, TX

http://www.theage.com.au/ftimages/2005/08/30/1125302540219.html

http://maps.google.com 6

Selection of Hurricanes

Storm Date (Name)

Central Pressure (mb)

Radius to Maximum Wind (km)

Saffir-Simpson Category

Observed Open Coast Surge (m)

Sep 1961 (Carla) 936 56 4 3.3 - 3.7

Sep 1967 (Beulah) 950 46 3 2.4 - 2.9

Jul 1970 (Celia) 944 17 3 2.7 - 2.8

Jul 1980 (Allen) 945 37 3 2.1 - 3.7

Aug 1999 (Bret) 953 19 3 0.9 - 1.5

nhc.noaa.gov

Selected historical storms• Bret, Beulah

• Carla with alternate track

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Projected Hurricane IntensificationPredict future storms:• Project intensification based on projected SST rise (Wigley 2004 with IPCC scenarios B1, A1B, A1FI)

• Modify historical storm intensity Intensification approximation:Knutson & Tuleya (2004, 2008)

8% intensification per 1 oC SST rise

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Projected Sea Level RiseSea level rise:• Eustatic rise projection (Wigley 2004 with IPCC scenarios B1, A1B, A1FI)

• Estimated historical subsidence rate: 4.6 mm/yr historical relative rate - 1.7 mm/yr historical eustatic rate = 2.9 mm/yr subsidence

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Projected Hurricane Intensification

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Flood Level Estimation

• ADCIRC – used for water levels

• SWAN – coupled with ADCIRC to determine wave setup

• XBEACH – barrier island is lowered to account for overwash and breaching

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Inundation and Damage EstimationFlood inundation:• In GIS framework• USGS topography

• Inundation elevation = Surge + Relative SLR + Wave setup ± Tide

Property damages:• In GIS framework• City of Corpus Christi parcel data

• FEMA (2001) loss estimation

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Results – Hurricane Bret

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Results – Hurricane Bret

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Results – Hurricane Beulah

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Results – Hurricane Beulah

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Results – Hurricane Carla

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Results – Hurricane Carla

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Flooding InundationInundation:• Bret:

• 1.2 to 1.6 times by 2030• 1.6 to 3.7 times by 2080

• Beulah:• 1.1 to 1.2 times by 2030• 1.2 to 1.8 times by 2080

• Carla (shifted):• 1.02 to 1.06 times by 2030• 1.06 to 1.25 times by 2080

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Property DamagesProperty Damages:• Bret:

• 2.5 to 5 times by 2030• 5 to 50 times by 2080

• Beulah:• 1.5 to 2 times by 2030• 2 to 4.3 times by 2080

• Carla (shifted):• 1.1 to 1.3 times by 2030• 1.3 to 2.1 times by 2080

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Parcel Damages – Residential & Small Businesses

Parcel Damages – Residential& Small Businesses:• Bret:

• 1.5 to 2.1 times by 2030• 2.1 to 7.3 times by 2080

• Beulah:• 1.1 to 1.2 times by 2030• 1.2 to 2.1 times by 2080

• Carla (shifted):• 1.1 to 1.4 times by 2030• 1.4 to 2.1 times by 2080

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Parcel Damages – Refineries

Parcel Damages – Refineries• Bret:

• 1 to 1.2 times by 2030• 1.2 to 9.2 times by 2080

• Beulah:• 1.1 to 1.2 times by 2030• 1.2 to 1.9 times by 2080

• Carla (shifted):• 1.1 to 1.3 times by 2030• 1.3 to 3.7 times by 2080

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Parcel Damages – Downtown

Parcel Damages – Downtown• Bret:

• 1 to 26 times by 2030• 26 to 382 times by 2080

• Beulah:• 1.2 to 1.5 times by 2030• 1.5 to 2.2 times by 2080

• Carla (shifted):• 1.003 to 1.004 times by 2030• 1.004 to 1.008 times by 2080

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Parcel Damages – Barrier Island

Parcel Damages – Barrier Island• Bret:

• 5.2 to 14.9 times by 2030• 14.9 to 126.6 times by 2080

• Beulah:• 1.7 to 2.9 times by 2030• 2.9 to 4.2 times by 2080

• Carla (shifted):• 1 to 1.01 times by 2030• 1.01 to 1.03 times by 2080

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• Inundated area:• Up to 1.7 times more by 2030• Up to 3.7 times more by 2080

• More frequently-occurring surge events have potential to have largest economic impact:

• $55M increase per 1oC of warming (Bret)• $75M increase per 1oC of warming (Beulah)• $210M increase per 1oC of warming (Carla, shifted)

• Climate change has the greatest impact on smaller storms• Barrier island inundation will occur more frequently

Some notes:• Economic evaluation only includes structural damages• The City of Corpus Christi has more topographic relief than most other coastal Texas communities

Conclusions

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Questions?

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