MORPHOLOGICAL IMPACT AND POST-STORM RECOVERY OF HURRICANE IVAN ALONG NW FLORIDA BARRIER-ISLAND COAST

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MORPHOLOGICAL IMPACT AND POST-STORM RECOVERY OF
HURRICANE IVAN ALONG NW FLORIDA BARRIER-ISLAND
COAST

• Presented by Rip Kirby
• University of South Florida
• Department of Geology
• Coastal Research Lab
• March 17, 2005
• SE GSA Meeting, Biloxi MS

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Survey Sites
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The 3 Top Line

• No problem. You can leave, well lock up when
  were done.

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The 2 Top Line

• Were location consultants for Jackie Chans
  new hurricane movie. His stunt man is in the car
  behind mesay, have you ever been in the movies,
  officer?

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The 1 Top Line

• Cmon, gimme a break, officer. This is our last
  survey site for the NW Florida beach safety
  surveyif we dont finish, thousands of
  registered voters, I mean people, could be
  adversely affectedhey, isnt Sheriff Holloway up
  for re-election?

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Tide Gauge Data
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St George Island

• SG1 looking ENE of the SG1 profile line area on
  9/14/04 _at_ 1815 EDT

PRE-STORM
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St George Island

• SG1 looking SSW along the SG1 profile line on
  9/14/04 _at_ 1740 EDT

PRE-STORM
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St George Island

• SG1 looking WSW at the SG2 profile line area on
  9/14/04 _at_ 1815 EDT

PRE-STORM
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St George Island

• SG1 looking ESE of the SG1 profile line on
  9/23/04 _at_ 0807 EDT

POST-STORM
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St George Island

• SG1 looking SSW along the SG1 profile line on
  9/23/04 _at_ 0815 EDT

POST-STORM
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St George Island

• SG1 looking WSW at the SG2 profile line area on
  9/23/04 _at_ 0816 EDT

POST-STORM
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SG1 - Survey Data
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St George Island

• SG2 looking NW from the back beach on 9/14/04 _at_
  1815 EDT

PRE-STORM
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St George Island

• SG2 looking NNW from the back beach on 9/14/04 _at_
  1803 EDT

PRE-STORM
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St George Island

• SG 2 looking WSW from the back beach on 9/23/04
  _at_ 0923 EDT

POST-STORM
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St George Island

• SG2 looking NW from the back beach on 9/23/04 _at_
  0923

POST-STORM
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SG2- Survey Data
Note no Jan data due to bad wx
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St Joe Peninsula

• SJ 1 - State park just north of the Eagle Harbor
  parking lot looking west along the SJ1 profile
  line on 9/14/04 _at_ 1538 EDT

PRE-STORM
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St Joe Peninsula

• SJ 1 - State park just north of the Eagle Harbor
  parking lot looking NNW of the SJ1 profile line
  on 9/23/04 _at_ 1051 EDT

POST-STORM
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St Joe Peninsula

• SJ 1 - State park just north of the Eagle Harbor
  parking lot looking ENE on the SJ1 profile line
  on 9/23/04 _at_ 1049 EDT

POST-STORM
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SJ1 - Survey Data
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St Joe Peninsula

• SJ 2 - residential area south of the state park
  on Sago Ave looking west along the SJ2 profile
  line on 9/14/04 _at_ 1615 EDT

PRE-STORM
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St Joe Peninsula

• SJ2- residential area on Sago Ave south of the
  state park looking north from the beach on
  9/23/04 _at_ 1129 EDT

POST-STORM
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St Joe Peninsula

• Residential area south of SJ2 profile line area
  looking SSE at an exposed geotube 250m south of
  the SJ2 beach area on 9/23/04 _at_ 1119 EDT

POST-STORM
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St Joe Peninsula

• Residential area 250m south of SJ2 profile line
  area looking north from an exposed geotube on
  the beach on 9/23/04 _at_ 1144 EDT

POST-STORM
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St Joe Peninsula

• Damage to building from undercut erosion
  amplified by the exposed geotube looking SW from
  the beach on 9/23/04 _at_ 1129 EDT. House was
  demolished in Feb 05.

POST-STORM
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SJ2 - Survey Data
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Inlet Beach
PRE-STORM

• IB1 - Looking north from the beach on 9/14/04 _at_
  1219 CDT.

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Inlet Beach

• IB1 - Looking east from the BP2 dune on 9/24/04
  _at_ 0917 CDT.

POST-STORM
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IB1 - Survey Data
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Inlet Beach
PRE-STORM

• IB2 - Looking NNE from the beach on 9/14/04 _at_
  1239 CDT.

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Inlet Beach
POST-STORM

• IB2 - Looking south from the IB2 benchmark on
  9/23/04 _at_ 1756 CDT.

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IB2 - Survey Data
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Inlet Beach
PRE-STORM

• IB1 - Looking east from the BP2 dune on 9/14/04
  _at_ 1305 CDT.

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Inlet Beach
POST-STORM

• IB3 - Looking south from the inlet on 9/23/04 _at_
  1644 CDT.

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Inlet Beach
POST-STORM

• IB3 - Looking east from the inlet on 9/23/04 _at_
  1644 CDT.

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Inlet Beach
POST-STORM

• IB3 - Looking SSW from the inlet on 9/23/04 _at_
  1642 CDT.

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IB3 - Survey Data
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Ft Walton Beach -Santa Rosa Island
PRE-STORM

• Beasley Park - Profile Line 3. Looking east from
  the BP2 dune on 9/14/04 _at_ 0916 CDT.

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Ft Walton Beach -Santa Rosa Island
PRE-STORM

• Beasley Park - Profile Line 3. Looking east from
  the BP2 dune on 9/14/04 _at_ 0917 CDT.

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Ft Walton Beach -Santa Rosa Island
PRE-STORM

• Beasley Park - Profile Line 3. Looking north
  along the BP3 profile on 9/14/04 _at_ 0940 CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• Beasley Park - Profile Line 3. Looking north
  along the BP3 profile on 9/24/04 _at_ 1012 CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• Beasley Park - Profile Line 3. Looking east from
  the BP2 dune on 9/24/04 _at_ 1259 CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• Beasley Park - Profile Line 3. Looking south
  along the BP3 profile on 9/24/04 _at_ 1524 CDT.

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BP3 - Survey Data
Note Jan data collection curtailed by fog
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Ft Walton Beach -Santa Rosa Island
PRE-STORM

• Beasley Park - Profile Line 2. Looking west at
  the BP2 dune on 9/14/04 _at_ 0900 CDT.

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Ft Walton Beach -Santa Rosa Island
PRE-STORM

• Beasley Park - Profile Line 2. Looking west at
  the BP2 dune on 9/14/04 _at_ 0910 CDT.

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Ft Walton Beach -Santa Rosa Island
PRE-STORM

• Beasley Park - Profile Line 2. Looking south
  from the BP2 dune on 9/14/04 _at_ 0914 CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• Beasley Park - Profile Line 2. Looking north
  from the beach at the BP2 dune on 9/24/04 _at_ 0928
  CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• BP2. Looking NE from the beach at the south side
  of the dune on 9/24/04 _at_ 1039 CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• BP2. Looking west from the benchmark at the
  north side of the dune on 9/24/04 _at_ 0933 CDT.

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BP2- Survey Data
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Ft Walton Beach -Santa Rosa Island
PRE-STORM

• Beasley Park - Profile Line 1. Looking west from
  the dune walk-over on 9/14/04 _at_ 0834 CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• Beasley Park - Profile Line 1. Looking N from
  the beach on 9/24/04 _at_ 1248 CDT.

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Ft Walton Beach -Santa Rosa Island
POST-STORM

• Beasley Park - Profile Line 1. Looking west from
  the dune on 9/24/04 _at_ 1234 CDT.

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BP1 - Survey Data
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Scarp - Some Things to Consider

• Continuous scarping requires a continuous dune
  line!
• Evidence of a strong longshore current is
  present.
• Scarping (collision regime) transitioned to
  overwash regime at the hurricane wind speed
  boundary.

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Signs of Longshore Current Damage

• These posts were bent parallel to shore. Other
  shore morphology displayed similar patterns.

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Rosemary Beach
Just west of the Inlet Beach survey area, the
beaches of South Walton were hit with severe
erosion. The scarping of these dunes exposed old
humic peat layers.
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Exposed Peat
The humic peat layers were exposed from Rosemary
Beach to Seagrove Beach some 12 miles to the west.
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Seagrove Beach
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Gulfview Heights Beach(west of Draper Lake)
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West end of Santa Rosa Island, due south of FWB
The top image was taken in July, the bottom image
in December, 2004
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Howdat happen??
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Navarre Beach
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Morphological Impacts

• Overwash was the dominant regime west of Destin
  to west of Navarre
• Between Destin and Inlet Beach, continuous dune
  scarping was dominant
• East of Inlet Beach, dune scarping was dominant
  on narrow beaches with a NW-SE alignment
• East of St Joe Peninsula, beach erosion decreased
  significantly
• There was a net loss of beach along the entire
  coastline of the study area

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Conclusions

• Large area, high energy hurricanes and tropical
  storms are major transgressive engines on barrier
  island morphology
• Beach renourishment efforts should focus on
  widening beaches as much as dune building
• Vegetation is critical to preventing a major
  collapse of an established dune field
• More study of longshore erosion currents during
  overwash and collision regime events is needed

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Questions??Please visit our web site
athttp//uweb.cas.usf.edu/jkirby/ivan-website/in
dex.htm

• Many thanks to Joseph D. Haber, Mark H. Horwitz,
  Paul O. Knorr, Marianne Caldwell, and Jennifer R.
  Krock of the USF Dept of Geology (the Ivan crew).
• This research was partially funded by a grant
  from the National Science Foundation.
• Kudos to the Emerald Coast Marine Institute and
  its student body for volunteering to help with
  the field work.
• A special thanks to my wife, Jane, for putting up
  with me for 31 years.