Transcript GEOLOGICAL SURVEY OF THE GULF SHORELINE FOLLOWING HURRICANE RITA Jim Gibeaut John Andrews, Tiffany Hepner, Roberto Gutierrez, Becky Smyth Bureau of Economic Geology John A.

GEOLOGICAL SURVEY OF THE GULF
SHORELINE FOLLOWING HURRICANE RITA
Jim Gibeaut
John Andrews, Tiffany Hepner, Roberto Gutierrez, Becky Smyth
Bureau of Economic Geology
John A. and Katherine G. Jackson School of Geosciences
The University of Texas at Austin
Funding from Texas General Land Office, NASA, and MMS
Second Annual Texas Coastal Law Conference, May 18, 19, 2006
Shoreline
Length
Gulf = 600 km
Bays = 9,400 km
Themes
•
Upper Texas shoreline vulnerability to storms
•
The differences in being on the left- or right-handsides of Hurricane Rita
•
Rita’s effects on Texas shoreline
•
Good things about storm surge
TEXAS SHORELINE DEVELOPMENT
Erosion
Sabine Pass
N
Galveston
Harbor
Accretion
Aransas
Pass
Matagorda
Ship
Channel
Mansfield
Channel
Bureau
of
Economic
Geology
0
50 mi
Brazos River
Delta
Shoreline changes
from 5000 years ago
Erosion
Accretion
After Morton (1979)
QAc5749c
Sand Trapped by Jetty, Southwest end of Bolivar Peninsula (08/07/98)
Relative Sea-Level Change
Pier 21 - Galveston
Average water level (cm)
180.0
160.0
140.0
120.0
100.0
60.0
40.0
20.0
0.0
1900
y = 0.652x - 1145.6
Global ocean-level rise
80.0
R2 = 0.9436
4.36 + 2.16 = 6.52 mm/yr
Local land subsidence
1910
1920
1930
1940
1950
1960
Year
1970
1980
1990
2000
2010
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Galveston Bay
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Bolivar Roads
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Matagorda Bay
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Colorado River
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Pass Cavallo
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Corpus Christi
Bay
Aransas
Pass
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High (>2m/yr) retreat rates = red
Baffin
Bay
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Brazos Santiago
Pass
Sabine
Pass
2060 Projected Shoreline
BARRIER ISLAND CROSS SECTION
A
Marsh
Upland
Tidal flat
Tidal
channel
Foredune crest
Foredune brink
Scarp
Berm
Foredune
Swash
zone
Surf zone
Breaker
zone
Bermcrest
Coppice
mounds
High tide
Low tide
Runnel
Burea
of
Economi
Geolog
A'
Barrier island
Back
barrier
Beach
Beach
ridges Foredune
Marsh
Washover
fan
Swash
bar
Longshore
bar
QAb9621c
#
BEG13
BOL01
Galveston
Bay
BEG10
#
GLO21
#
#
#
#
GLO19
#
#
GLO17
#
BEG09
#
GLO15 # # GLO18
GLO13
#
GLO16
#
GLO14
GLO09 GLO11
#
##
GLO12
BEG01
T GLO10
$
GLO08
#
Pleasure Pier
GLO06
#
Tide Gauge
# ##
BEG07
# ##
GLO07
##
GLO03
GLO02
GLO01
FOI01
#
#
##
#
#
#
#
#
#
#
#
GLO24
#
#
GLO23
GLO22
GLO20
Bouy Station
No. 42035
T
$
#
GLO05 BEG02
BEG03
BEG05
BEG04
Texas
GLO04
N
#
WST04
#
BEG12
Gulf of
Mexico
BEG08
10
0
10
20 Kilometers
Galveston Island State Park, Pre-Frances, August 8, 1998 (profile BEG-02)
Galveston Island State Park, Post-Frances, September 16, 1998 (profile BEG-02)
BEG02 Galveston Island State Park
1998 Aug 8
1998 Sep 16
1998 Oct 7
2002 Sep 18
2003 Sep 3
2006 April 27
Height (m)
3
2
1
0
vertical exaggeration = 10:1
-50
-25
0
25
Distance from Monument (m)
50
75
100
Galveston Island State Park, Pre-Claudette, February 4, 2003 (profile BEG02)
Galveston Island State Park, Post-Claudette, September 3, 2003 (profile BEG-02)
Galveston Island State Park, April 28, 2005 (profile BEG-02)
Galveston Island State Park, April 27, 2006 (profile BEG-02)
POST-STORM BEACH RECOVERY
ft m
10 3
Storm erosion
ft m
10 3
Stage 1. Forebeach accretion
Vegetation line
Vegetation line
Berm crest
5
5
Post-storm profile
0
0
Sea level
ft m
10 3
Stage 2. Backbeach aggradation
Sea level
ft m
10 3
Stage 3 & 4. Dune restoration
and revegetation
Vegetation line
Vegetation line
Berm crest
5
0
Sea level
5
0
Sea level
Erosion
Bureau
of
Economic
Geology
Berm crest
Deposition
Morton, Paine, & Gibeaut, (1994)
QAa4842c
Bermuda Beach on Galveston, Island
Pirate’s Beach on Galveston Island
Bolivar Peninsula, June 13, 2001, (profile GLO-20)
Lidar Topographic Images
Gilchrist East Geotube Area
1,000 ft
1997
Nov
Rollover Pass
Gulf of Mexico
1998
PreFrances
1998
PostFrances
2000
May
geotube
2001
July
geotube
QAd496
1961 – post Carla
Jamaica Beach
Galveston Isl.
2002
Jamaica Beach
Galveston Isl.
Tropical Storm Frances 1998
Data from Pleasure Pier tide gauge on
Gulf side of Galveston Island
0.5
1
0.4
2.4
0.8
0.3
2
0.2
1.6
1.2
0.8
6-Sep
Sigma (m)
Water level (m)
2.8
1.2
0.6
0.4
0.1
Extreme Area
EA= 36 m2,hr
0
8-Sep
10-Sep
12-Sep
14-Sep
16-Sep
0.2
0
Water level times sigma (m2)
3.2
Storm Comparison
WATER LEVEL X SIGMA
STORM
PEAK (m2)
EA (hr m2)
TS Dean Jul-95
HU Opal Oct-95
TS Josephine Oct-96
0.546
0.678
0.825
HOURS >
EXTREME
17
66
79
HU Danny Jul-97
0.035
0
0.0
TS Charley Aug-98
TS Frances Sep-98
0.668
1.138
30
119
3.8
36.0
TS Allison Jun-01
TS Fay Sep-02
0.484
0.926
5
81
0.2
13.6
HU Isadore Sep-02
0.757
72
11.2
HU Lili Oct-02
0.783
11
2.3
0.9
6.1
12.7
1998
Post Tropical Storm Fay
Surfside, Texas
(Sigma) X (Water level)
Rita and Frances Compared
Hurricane Rita
1.2
Tropical Storm Frances
0.8
Frances EA= 36
Rita EA= 3.3
0.4
0
0
24
48
72
96
Duration (hours)
120
144
Hurricane Rita
September 23, 2006, 21:15 UTC
GOES-12 1 km visible imagery
Predicted Path
Cumulative Wind Distribution
Figure 1. WSR-88D reflectivity
image from WFO Lake Charles
taken at 2:42 a.m. CDT
September 24, 2005.
Modeled
Water
Level
Water
Level (m)
Wind Direction
&
Relative Speed
Measured at
offshore buoy
#42035
ADCIRC hydrodynamic model
University of North Carolina
9/22 21:00
Modeled
Water
Level
Water
Level (m)
ADCIRC hydrodynamic model
University of North Carolina
9/23 03:00
Modeled
Water
Level
Water
Level (m)
ADCIRC hydrodynamic model
University of North Carolina
9/23 15:00
Modeled
Water
Level
Water
Level (m)
ADCIRC hydrodynamic model
University of North Carolina
9/23 21:00
Modeled
Water
Level
Water
Level (m)
ADCIRC hydrodynamic model
University of North Carolina
9/24 03:00
Modeled
Water
Level
Water
Level (m)
ADCIRC hydrodynamic model
University of North Carolina
9/24 09:00
Modeled
Water
Level
Water
Level (m)
ADCIRC hydrodynamic model
University of North Carolina
9/24 15:00
Modeled
Water
Level
Water
Level (m)
ADCIRC hydrodynamic model
University of North Carolina
9/24 21:00
Water level
1
0.8
0.8
0.4
0.6
0
0.4
-0.4
0.2
-0.8
0
21-Sep-05
22-Sep-05
23-Sep-05
24-Sep-05
25-Sep-05
Wind speed (m/s)
27-Sep-05
Wind speed
30
B.
26-Sep-05
Wind direction
300
20
200
10
100
0
0
C.
Wave height (m)
21-Sep-05
22-Sep-05
23-Sep-05
24-Sep-05
25-Sep-05
26-Sep-05
27-Sep-05
5
Wave height
4
Wave period
12
Wave direction
300
3
200
2
100
1
0
0
21-Sep-05
22-Sep-05
23-Sep-05
24-Sep-05
25-Sep-05
26-Sep-05
27-Sep-05
10
8
6
4
2
Wave period (s)
Predicted tide
Sigma
(Sigma) X ( Water level)
Galveston
Rita
Conditions
1.2
Wave direction from 0 degrees north
Wind direction from 0 degrees north
A.
Water level above msl (m)
Sigma
Sigma X Water level
LA
Calcasieu Pass
TX
Sabine
Pass
Rollover
Pass
Rita Landfall
University of Texas Airborne
Topographic Lidar System
(Optech model ALTM1225)
GPS satellites
Aircraft GPS
La
se
rs
ca
nl
in
es
ALTM laser
and IMU
GPS ground
reference station
Flight direction
#
BEG13
BOL01
Galveston
Bay
BEG10
#
GLO21
#
#
#
#
GLO19
#
#
GLO17
#
BEG09
#
GLO15 # # GLO18
GLO13
#
GLO16
#
GLO14
GLO09 GLO11
#
##
GLO12
BEG01
T GLO10
$
GLO08
#
Pleasure Pier
GLO06
#
Tide Gauge
# ##
BEG07
# ##
GLO07
##
GLO03
GLO02
GLO01
FOI01
#
#
##
#
#
#
#
#
#
#
#
GLO24
#
#
GLO23
GLO22
GLO20
Bouy Station
No. 42035
T
$
#
GLO05 BEG02
BEG03
BEG05
BEG04
Texas
GLO04
N
#
WST04
#
BEG12
Gulf of
Mexico
BEG08
10
0
10
20 Kilometers
Height relative to datum (meters)
Galveston Island State Park
1
Dunes
Galveston Island State Park (profile BEG-02)
September 19, 2005
September 29, 2005
0.5
0
-0.5
-1
water line
-1.5
-2
0
20
40
Distance from datum (meters)
60
80
Galveston Island State Park Area
Erosion/
Deposition
#
BEG13
BOL01
Galveston
Bay
BEG10
#
GLO21
#
#
#
#
GLO19
#
#
GLO17
#
BEG09
#
GLO15 # # GLO18
GLO13
#
GLO16
#
GLO14
GLO09 GLO11
#
##
GLO12
BEG01
T GLO10
$
GLO08
#
Pleasure Pier
GLO06
#
Tide Gauge
# ##
BEG07
# ##
GLO07
##
GLO03
GLO02
GLO01
FOI01
#
#
##
#
#
#
#
#
#
#
#
GLO24
#
#
GLO23
GLO22
GLO20
Bouy Station
No. 42035
T
$
#
GLO05 BEG02
BEG03
BEG05
BEG04
Texas
GLO04
N
#
WST04
#
BEG12
Gulf of
Mexico
BEG08
10
0
10
20 Kilometers
Surfside Beach Area
Surfside Beach
Surfside Beach
Surfside Beach
Surfside Beach
Washover Deposition
Surfside Beach
#
BEG13
BOL01
Galveston
Bay
BEG10
#
GLO21
#
#
#
#
GLO19
#
#
GLO17
#
BEG09
#
GLO15 # # GLO18
GLO13
#
GLO16
#
GLO14
GLO09 GLO11
#
##
GLO12
BEG01
T GLO10
$
GLO08
#
Pleasure Pier
GLO06
#
Tide Gauge
# ##
BEG07
# ##
GLO07
##
GLO03
GLO02
GLO01
FOI01
#
#
##
#
#
#
#
#
#
#
#
GLO24
#
#
GLO23
GLO22
GLO20
Bouy Station
No. 42035
T
$
#
GLO05 BEG02
BEG03
BEG05
BEG04
Texas
GLO04
N
#
WST04
#
BEG12
Gulf of
Mexico
BEG08
10
0
10
20 Kilometers
Treasure I.
Subdivision
at San Luis
Pass
Treasure Island Subdivision on Follets Island, Tx
Treasure Island Subdivision on Follets Island, Tx
Treasure Island Subdivision on Follets Island, Tx
Washover Deposition
Treasure Island Subdivision on Follets Island, Tx
#
BEG13
BOL01
Galveston
Bay
BEG10
#
GLO21
#
#
#
#
GLO19
#
#
GLO17
#
BEG09
#
GLO15 # # GLO18
GLO13
#
GLO16
#
GLO14
GLO09 GLO11
#
##
GLO12
BEG01
T GLO10
$
GLO08
#
Pleasure Pier
GLO06
#
Tide Gauge
# ##
BEG07
# ##
GLO07
##
GLO03
GLO02
GLO01
FOI01
#
#
##
#
#
#
#
#
#
#
#
GLO24
#
#
GLO23
GLO22
GLO20
Bouy Station
No. 42035
T
$
#
GLO05 BEG02
BEG03
BEG05
BEG04
Texas
GLO04
N
#
WST04
#
BEG12
Gulf of
Mexico
BEG08
10
0
10
20 Kilometers
Pirates Beach Geo Textile Tube, Galveston I., Profile GAL-20 Location
#
BEG13
BOL01
Galveston
Bay
BEG10
#
GLO21
#
#
#
#
GLO19
#
#
GLO17
#
BEG09
#
GLO15 # # GLO18
GLO13
#
GLO16
#
GLO14
GLO09 GLO11
#
##
GLO12
BEG01
T GLO10
$
GLO08
#
Pleasure Pier
GLO06
#
Tide Gauge
# ##
BEG07
# ##
GLO07
##
GLO03
GLO02
GLO01
FOI01
#
#
##
#
#
#
#
#
#
#
#
GLO24
#
#
GLO23
GLO22
GLO20
Bouy Station
No. 42035
T
$
#
GLO05 BEG02
BEG03
BEG05
BEG04
Texas
GLO04
N
#
WST04
#
BEG12
Gulf of
Mexico
BEG08
10
0
10
20 Kilometers
Rollover Pass, Tx
2005/10/07
Rollover Pass, Tx
Bolivar Peninsula, Tx
Gulf
Bolivar Peninsula, Tx
#
BEG13
BOL01
Galveston
Bay
BEG10
#
GLO21
#
#
#
#
GLO19
#
#
GLO17
#
BEG09
#
GLO15 # # GLO18
GLO13
#
GLO16
#
GLO14
GLO09 GLO11
#
##
GLO12
BEG01
T GLO10
$
GLO08
#
Pleasure Pier
GLO06
#
Tide Gauge
# ##
BEG07
# ##
GLO07
##
GLO03
GLO02
GLO01
FOI01
#
#
##
#
#
#
#
#
#
#
#
GLO24
#
#
GLO23
GLO22
GLO20
Bouy Station
No. 42035
T
$
#
GLO05 BEG02
BEG03
BEG05
BEG04
Texas
GLO04
N
#
WST04
#
BEG12
Gulf of
Mexico
BEG08
10
0
10
20 Kilometers
LA
Calcasieu Pass
TX
Sabine
Pass
Rollover
Pass
Rita Landfall
2005/10/07
Texas Point National Wildlife Refuge
McFaddin National Wildlife Refuge
LA
Calcasieu Pass
TX
Sabine
Pass
Rollover
Pass
Rita Landfall
Holly Beach, LA post Rita
Photo by Tom MacKenzie
USFWS
Discussion/Conclusions
•
•
•
•
•
The upper Texas Gulf shoreline is highly vulnerable to storms
and this vulnerability is increasing
– Ongoing shoreline retreat
– Small or non-existent foredune complexes
– Loss of wetlands
– New development
Rita caused large changes along the Gulf shoreline of Louisiana
but had relatively little effect along the Texas shoreline
Rita affected developments with preexisting erosion problems
Storm overwash deposits help maintain coastal environments
undergoing relative sea-level rise
As always, we may not be so lucky next time
Slide Courtesy of Dr. Gordon Wells
Center for Space Research
The University of Texas at Austin