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UFL/COEL-95/006
Supplement to "Comparisons of Erosion Models for
January 4, 1992, Storm at Ocean City, Maryland"
Evaluation Study and Comparison of Erosion Models and
Effects of Seawalls for Coastal Construction Control Line
Task Id: Compare Models with Results From Hurricane
Eloise and Other Data
by
Jie Zheng
and
Robert G. Dean
February, 1995
Prepared for:
Department of Environmental Protection
Supplement to "Comparisons of Erosion Models for
January 4, 1992, Storm at Ocean City, Maryland"
Evaluation Study and Comparison of Erosion Models and
Effects of Seawalls for Coastal Construction Control Line
Task 1 d: Compare Models with Results From
Hurricane Eloise and Other Data
February 1995
Prepared For:
Department of Environmental Protection
Prepared By:
Jie Zheng and Robert G. Dean
Coastal and Oceanographic Engineering Department
University of Florida
INTRODUCTION
The Ocean City, Maryland beach was nourished by the state of Maryland and Federal
Government in 1988, 1990 and 1991 to protect the city against storm damage. The entire project was
finished in August 1991. After the project, a series of storms occurred in late 1991 and early 1992.
Among these 1991-1992 winter storms, the January 4, 1992 storm was very severe with a peak
storm surge of 6.6 feet.
The previous technical report (UFL/COEL-95/002) "Comparison of erosion models for
January 4, 1992, storm at Ocean City, Maryland" compared the numerical results of beach erosion
for the January 4, 1992, storm with available surveys. The initial pre-storm profiles were surveyed
on November 2-4, 1991, and the post-storm profiles were surveyed on January 11, 1992. In this
period, an additional storm occurred on November 11, 1991, which was not considered in the report
referenced above.
During a meeting to discuss the project "Dune erosion models and effects of seawalls", held
in the Tallahassee, Florida vicinity on January 3-4, 1995, Professor David L. Kriebel recommended
that the numerical model simulation include both storms (November 11, 1991 and January 4, 1992)
to be more consistent with the measured pre- and post-storm profiles. Accordingly, this report
includes the effects of two storms and is a supplement to the previous report (UFL/COEL-95/002).
In the following study, five models CCCL, EDUNE, SBEACH (version 2.0), SBEACH
(version 3.0) and CROSS, are applied. Seven survey lines extending from south of 37th Street to
north of 124th Street in Ocean City are investigated. The median grain size of the beach is 0.35 mm
for all seven profiles [Stauble et. al 1993]. The input parameters for each model are selected to be
consistent with the conditions for which the model was calibrated.
STORM CHARACTERISTICS
In this paper, water depth and profile elevation are referenced to the NGVD (National
Geodetic Vertical Datum), which lies 0.07 feet below mean sea level for Ocean City. The significant
wave height, wave period and storm surge time histories during the storms were measured by two
gages located just offshore of Ocean City in water depths of 10 meters. These gages were installed
by the Coastal Engineering Research Center, U.S. Army Engineering Waterways Experiment Station.
The results are shown in Figures 1 and 2 for the November 11, 1991 and January 4, 1992 storms,
20 40 60 80 100 120
time [hr]
140 160
15 -------------,------------
15
5 . . . . . .
20 40 60 80
time [hr]
100 120 140
40 60 80
time [hr]
100
120
140
160
Fig. 1 Water level, significant wave height and wave period time history for November 11, 1991,
storm at Ocean City, Maryland (From Stauble et. al [1993]).
-5L
0
ii:
4:
(i,
.4-
160
........... ........ _.. .. .. ... .......
IIIIIIi :
I li ll
(
(
10
10
S.\e / \ t-up
S ............... ....... .............................
a:,
-5
0 20 40 60 80 100
time [hr]
20 -15
c-
-a 15 -
:: .. ... . . .. . . .
c:: 0
: 0 20 40 60 80 100
time [hr]
20
0C
a:)
a:, 10
5
0 20 40 60 80 100
time [hr]
Fig. 2 Water level, significant wave height and wave period time history for January 4, 1992, storm
at Ocean City, Maryland (From Kraus and Wise [1992]).
respectively. Since the storm surge was measured in a water depth of 10 meters, wave induced set-up
was not incorporated in these measurements. In the numerical simulations, wave set-up, S, at the
shoreline is calculated according to the instantaneous breaking wave height as:
S 0.375K H= 0.238Hb (1)
1+0.375K2
Where K is the ratio of wave height to water depth inside the surf zone and is taken here as equal to
0.78. The water level time histories of the two storms including the wave set-up are presented as
dashed lines in Figures 1 and 2. Wave run-up is included in EDUNE and CROSS models. Hunt's
wave run-up model is applied to establish the run-up height, R, as:
R=FRHb m (2)
Where R is measured vertically upward from the still water level, FR is a run-up coefficient and is
set to 1 for the following study, m is the beach slope averaged from the run-up limit to the wave
breaking point, and Lo is the deep water wave length.
INPUT CASE DESIGN
The input parameters for each model in this study are selected to represent the conditions for
which each model was calibrated. Sensitivities of wave run-up, wave set-up and water active depth
are tested in the EDUNE and CROSS models. The cases run for each model are described briefly
as follows:
(1) CCCL
The input dune slope (beach slope above instantaneous water level) is set to 1 as default.
Wave set-up is calculated by Eq.(1) according to the significant wave heights shown in Figs. 1 and
2. No wave run-up is included in this model consistent with the manner in which this model was
calibrated. The input water level during a storm is given by adding the set-up to the measured storm
surge. The significant wave height input at each time step is used as regular wave height in the
CCCL. After running two storms, a factor of 2.5 is applied to the profile recession for those contours
that receded.
(2) SBEACH
Both versions of SBEACH model are believed to incorporate wave run-up and set-up. The
maximum slope that the profile is allowed to achieve is required and is set to 17.50 as a default
condition; this corresponds to a slope of 0.32. The wave conditions used in the SBEACH model
simulations are the same as the measurements shown in Figs. 1 and 2. Both versions of SBEACH
model provide the choice of wave type (monochromatic or irregular). The irregular wave which
requires the input of significant wave height time series is chosen for this study.
(3) EDUNE
The input dune slope is set to 1 as a default and the input shoreline slope is taken as 0.05
which is the average shoreline slope of the measured pre-storm profiles. The input significant wave
height is applied as a regular wave height for each time step. Four combinations of run-up and set-up
are tested and denoted as Case (a), Case (b), Case (c) and Case (d). They are described as
Case(a) : Run-up is fixed as 3 and 5 feet for November 11, 1991 and January 4, 1992, storms,
respectively. In accordance with recommendations by Professor David Kriebel, these values are
based on the run-up calculated by Hunt's equation for the maximum significant wave height in the
storm. No set-up is included in the simulations.
Case(b) : The set-up is given by Eq.(1) according to the instantaneous significant wave
height. The calculated maximum values of set-up for the two storms are 2.2 and 3.1 feet,
respectively. After including the set-up in the model, the fixed run-up values are reduced to 0.8 and
1.9 feet for two storms, respectively.
Case(c): The run-up is calculated by Eq.(2) and no set-up is included in the modeling.
Case(d): The set-up is given by Eq.(1) and the run-up is set as the value calculated from
Eq.(2) after subtracting the value of the corresponding set-up.
(4) CROSS
The dune slope is equal to 1 as a default condition and the shoreline slope is set to the
average slope value for measured pre-storm profiles (0.05). A Rayleigh distributed random wave
height series is generated by the program according to the input significant wave height time history.
The sensitivity of active water depth and different combinations of run-up and set-up are studied.
Four cases are investigated.
Case(a): The run-up is calculated by Eq.(2) and no set-up is included. The active water depth
is the same as the in coming breaking wave height.
Case(b) : The set-up is given by Eq.(1) and the run-up is set as the value calculated from
Eq.(2) after subtracting the value of corresponding set-up. The active water depth is the same as the
in coming breaking wave height. The conditions of this case are the same as those for which the
CROSS model was calibrated.
Case(c) : The run-up and set-up are the same as Case (a). The active water depth is 1.28 times
the incoming breaking wave height.
Case(d) : The run-up and set-up are same as Case (b).The active water depth is 1.28 times
the incoming breaking wave height.
RESULTS
The numerical results from the five models are evaluated in terms of several parameters. A
comparison of measured and predicted profile changes is provided by the residual parameter, Res,
defined as a non-dimensional variable
n
i=l
E (hi -h )2
Res =
(hnbi hai)2
Where h is the water depth, the subscribes "p" and "m" denote predicted and measured, respectively,
"b" and "a" indicate before and after storm conditions, respectively, and i represents the "i" th
location on the profile. The minimum possible value of Res is zero, which corresponds to a perfect
simulation. The dune erosion is represented by the eroded volume and beach retreat at the 10 foot
contour. To provide a measure of erosion and retreat, two different errors are presented: the root
mean square error, ERR,,, and the algebraical error, ERRa,. These are expressed as:
n
E (S -Sm)2
ERR, = (4)
j=1
n
ERRave = = (5)
E Smj
j=1
Where S is an eroded volume or beach retreat, the subscripts "p" and "m" again represent the
predicted and measured values respectively, and j means the "j" th beach profile. ERRrs represents
a factor of simulation accuracy and ERRave provides a measure of over or under-prediction of
erosion.
Comparisons between predicted and measured profiles of the seven available survey lines
are presented in Figs. 3 9. The residuals, eroded volumes and beach retreat at the 10 foot contour
are shown in Tables 1 7. Because the net volume changes between measured pre- and post-storm
profiles are quite different from zero due to gradients of longshore sediment transport, in addition
to the measured profile, a version is included by shifting each post-storm profile a horizontal distance
to yield zero net volume change (refer to the previous report, UFL/COEL-95/002). In the tables,
"without adjustment" means data given by the original measured post-storm profiles, while "with
adjustment" means data given by horizontally shifted post-storm profiles. The onshore limit of
predicted eroded volume for each profile is determined by the onshore cross over point of the
predicted post-storm and the measured pre-storm profiles, while the offshore limit is truncated by
the offshore cross over point of the shifted measured post-storm and the measured pre-storm profiles.
The seven profile averaged residuals are shown in Table 8. The errors for eroded volume and retreat
at the 10 foot contour are presented in Tables 9 and 10, respectively. It appears that Case (b) for
CROSS and Case (d) of EDUNE provide the smallest residuals. CCCL overpredicts the eroded
volume, EDUNE and the two versions of SBEACH underpredict it, and Case (b) of CROSS gives
almost ideal results. For beach retreat at the 10 foot contour, Cases (b) and (d) of EDUNE and Case
(b) of CROSS provide very good results, and CCCL overpredicts by 56% on the average.
SENSITIVITY DISCUSSION
(1) Active Water Depth
The CROSS model was calibrated with the active water depth the same as the incoming
is the same as the in coming breaking wave height.
Case(b) : The set-up is given by Eq.(1) and the run-up is set as the value calculated from
Eq.(2) after subtracting the value of corresponding set-up. The active water depth is the same as the
in coming breaking wave height. The conditions of this case are the same as those for which the
CROSS model was calibrated.
Case(c) : The run-up and set-up are the same as Case (a). The active water depth is 1.28 times
the incoming breaking wave height.
Case(d) : The run-up and set-up are same as Case (b).The active water depth is 1.28 times
the incoming breaking wave height.
RESULTS
The numerical results from the five models are evaluated in terms of several parameters. A
comparison of measured and predicted profile changes is provided by the residual parameter, Res,
defined as a non-dimensional variable
n
i=l
E (hi -h )2
Res =
(hnbi hai)2
Where h is the water depth, the subscribes "p" and "m" denote predicted and measured, respectively,
"b" and "a" indicate before and after storm conditions, respectively, and i represents the "i" th
location on the profile. The minimum possible value of Res is zero, which corresponds to a perfect
simulation. The dune erosion is represented by the eroded volume and beach retreat at the 10 foot
contour. To provide a measure of erosion and retreat, two different errors are presented: the root
mean square error, ERR,,, and the algebraical error, ERRa,. These are expressed as:
n
E (S -Sm)2
ERR, = (4)
j=1
breaking wave height. In this sensitivity study, two different active water depths have been
investigated. It appears that beach and dune erosion is dependent on the active water depth.
Increasing the active water depth by 28%, the eroded volume increases by about 30-40% and the
retreat at the 10 foot contour increases by about 20-30%.
(2) Wave Run-up and Set-up
In the EDUNE model, both fixed run-up and Hunt's run-up model are tested. It was found
that a properly chosen fixed run-up yields profiles that are approximately the same as those from
Hunt's run-up model. The appropriate fixed run-up is that which occurs at the peak of the storm.
Wave set-up is an important factor in both the EDUNE and CROSS models. After including set-up,
the run-up should be reduced by the value of the corresponding set-up. This is in accordance with
Hunt's experiments. The case with run-up only predicts much less dune erosion than the
corresponding case with combinations of run-up and set-up although water reaches to the same
upper limit in both cases. Overall, the combination of set-up and run-up gives more reasonable
results in both the EDUNE and CROSS models.
SUMMARY AND CONCLUSIONS
The applicability of five numerical models to represent beach and dune erosion at Ocean
City, Maryland resulting from the major storms of November 11, 1991 and January 4, 1992 have
been examined. The five models CCCL, EDUNE, SBEACH (two versions) and CROSS are
applied and compared with the measured profiles. Seven profiles located from 37th Street to 124th
Street were surveyed on November 2, 1991, and January 11, 1992, before and after two storms
respectively. Since the net volume changes in most profiles are quite different from zero due to
gradients in long shore sediment transport, an "adjusted profile" is also evaluated as established by
shifting the active profile horizontally a proper distance to yield a zero net volume change. The
profiles from the numerical simulations are compared with both measured and shifted profiles. The
input parameters in each model are designed to fit the conditions of their respective calibrations. The
"2.5" factor is included in the CCCL model in this application. The sensitivities of model predictions
to wave run-up, wave set-up and active water depth are studied in EDUNE and CROSS models.
Three error parameters are defined to evaluate the agreement between the predicted and
measured profiles. First a residual non-dimensional error is used to evaluate depth changes over the
entire active profile. Two kinds of error (root mean square and algebraic average) are given to
estimate the prediction of dune erosion. Case (b) of CROSS yields the smallest residual, the CCCL
model overpredicts the eroded volume, EDUNE and two versions of SBEACH underpredict it, while
Case (b) of CROSS agrees with measured eroded volumes very well. For beach retreat at the 10 foot
contour, Cases (b) and (d) of EDUNE and Case (b) of CROSS provide good predictions, the CCCL
model overpredicts average beach retreat by about 56% and the two SBEACH models underpredict
by about 60%. Overall, Case (b) of CROSS provides quite good results for both residuals and dune
erosion.
The predicted dune erosion is quite sensitive to active water depth. Increasing the active
water depth by 28% results in a 30-40% increasing in average eroded volume and a 20-30%
increasing in average beach retreat at the 10 foot contour. A properly chosen fixed run-up yields very
similar predictions to Hunt's run-up model with a time-varying run-up. The appropriate fixed run-up
is that which occurs at the peak of the storm. Wave set-up plays an important role in the prediction
of erosion. When using Hunt's equation, after including set-up in a model, the run-up should be
reduced by the value of the corresponding set-up to be consistent with Hunt's experimental set-up
and analysis method. The cases with combinations of set-up and run-up yield smaller residuals and
more reasonable dune erosion than the cases with run-up only. This result is acceptable because both
run-up and set-up occur in the field during storms. For conducting a better numerical simulation, the
use of combined set-up and run-up together is highly recommended in the EDUNE and CROSS
models.
The overprediction by 56% of the 10 foot contour retreat by the CCCL model is consistent
with the application of the model for setting Florida's Coastal Construction Control Line to
incorporate a reasonable percentage of the longshore variability of dune erosion.
breaking wave height. In this sensitivity study, two different active water depths have been
investigated. It appears that beach and dune erosion is dependent on the active water depth.
Increasing the active water depth by 28%, the eroded volume increases by about 30-40% and the
retreat at the 10 foot contour increases by about 20-30%.
(2) Wave Run-up and Set-up
In the EDUNE model, both fixed run-up and Hunt's run-up model are tested. It was found
that a properly chosen fixed run-up yields profiles that are approximately the same as those from
Hunt's run-up model. The appropriate fixed run-up is that which occurs at the peak of the storm.
Wave set-up is an important factor in both the EDUNE and CROSS models. After including set-up,
the run-up should be reduced by the value of the corresponding set-up. This is in accordance with
Hunt's experiments. The case with run-up only predicts much less dune erosion than the
corresponding case with combinations of run-up and set-up although water reaches to the same
upper limit in both cases. Overall, the combination of set-up and run-up gives more reasonable
results in both the EDUNE and CROSS models.
SUMMARY AND CONCLUSIONS
The applicability of five numerical models to represent beach and dune erosion at Ocean
City, Maryland resulting from the major storms of November 11, 1991 and January 4, 1992 have
been examined. The five models CCCL, EDUNE, SBEACH (two versions) and CROSS are
applied and compared with the measured profiles. Seven profiles located from 37th Street to 124th
Street were surveyed on November 2, 1991, and January 11, 1992, before and after two storms
respectively. Since the net volume changes in most profiles are quite different from zero due to
gradients in long shore sediment transport, an "adjusted profile" is also evaluated as established by
shifting the active profile horizontally a proper distance to yield a zero net volume change. The
profiles from the numerical simulations are compared with both measured and shifted profiles. The
input parameters in each model are designed to fit the conditions of their respective calibrations. The
"2.5" factor is included in the CCCL model in this application. The sensitivities of model predictions
to wave run-up, wave set-up and active water depth are studied in EDUNE and CROSS models.
Three error parameters are defined to evaluate the agreement between the predicted and
measured profiles. First a residual non-dimensional error is used to evaluate depth changes over the
Table L. The predicted residuals, eroded volumes and retreat for the beach at 37th Street.
Residual eroded vol. retreat at 10 ft
Model Case
w/o adjust. with adjust. ft3 / ft contour ( ft)
w/o adjust. 72.6 6.88
Measurement
with adjust. 522.1 43.93
CCCL 1.286 0.443 895.3 69.50
Case (a) 0.588 0.512 83.6 15.74
Case (b) 0.540 0.272 288.1 36.37
EDUNE
Case (c) 0.580 0.547 86.3 7.46
Case (d) 0.519 0.265 304.2 38.82
Case (a) 0.578 0.491 261.4 15.75
Case (b) 0.440 0.135 465.9 48.94
CROSS
Case (c) 0.941 0.851 343.8 18.95
Case (d) 0.772 0.477 584.8 53.77
SBEACH (version 2.0) 1.074 1.075 176.7 11.66
SBEACH ( version 3.0) 0.664 0.613 269.7 15.87
Table 2. The predicted residuals, eroded volumes and retreat for the beach at 45th Street.
Residual eroded vol. retreat at 10 ft
Model Case
w/o adjust, with adjust, ft3 / ft contour (ft)
w/o adjust. 219.1 27.33
Measurement
with adjust. 316.7 36.53
CCCL 1.067 0.851 649.7 60.16
Case (a) 0.624 0.604 143.5 21.35
Case (b) 0.463 0.430 272.7 44.29
EDUNE
Case (c) 0.666 0.652 115.6 16.68
Case (d) 0.441 0.404 296.6 42.99
Case (a) 0.561 0.535 211.8 18.76
Case (b) 0.257 0.229 385.6 50.04
CROSS
Case (c) 1.025 0.947 288.8 23.02
Case (d) 0.761 0.677 499.9 58.67
SBEACH ( version 2.0) 1.018 0.970 137.2 9.72
SBEACH (version 3.0) 0.734 0.711 250.7 22.28
Table 3. The predicted residuals, eroded volumes and retreat for the beach at 56th Street.
Residual eroded vol. retreat at 10 ft
Model Case
w/o adjust. with adjust. ft3 / ft contour ( ft)
w/o adjust. 98.2 7.56
Measurement
with adjust. 29.3 1.11
CCCL 1.505 1.761 306.5 38.90
Case (a) 1.812 1.725 -57.8 12.23
Case (b) 1.087 1.039 34.4 20.58
EDUNE
Case (c) 1.773 1.688 -20.6 5.22
Case (d) 1.037 0.995 59.9 22.56
Case (a) 1.320 1.313 81.3 8.76
Case (b) 1.019 1.093 238.0 37.95
CROSS
Case (c) 2.400 2.489 175.1 13.24
Case (d) 2.631 2.852 403.3 47.91
SBEACH (version 2.0 ) 2.971 2.976 41.6 7.47
SBEACH (version 3.0 ) 1.588 1.528 64.1 10.90
Table 4. The predicted residuals, eroded volumes and retreat for the beach at 63rd Street.
Residual eroded vol. retreat at 10 ft
Model Case
w/o adjust. with adjust. ft3 / ft contour ( ft)
w/o adjust. 481.8 97.70
Measurement
with adjust. 478.6 97.16
CCCL 1.960 1.966 573.9 65.87
Case (a) 0.797 0.795 185.0 29.31
Case (b) 0.519 0.518 267.1 45.12
EDUNE
Case (c) 0.928 0.926 143.4 22.66
Case (d) 0.521 0.519 263.8 42.71
Case (a) 0.863 0.862 164.7 21.50
Case (b) 0.374 0.372 330.1 49.10
CROSS Case (c) 1.220 1.221 295.1 31.32
Case (d) 0.866 0.866 507.7 66.21
SBEACH (version 2.0 ) 0.803 0.802 142.7 15.07
SBEACH (version 3.0 ) 0.646 0.645 268.4 17.62
Table 5. The predicted residuals, eroded volumes and retreat for the beach at 74th Street.
Residual eroded vol. retreat at 10 ft
Model Case
w/o adjust. with adjust, ft3 / ft contour ( ft)
w/o adjust. 538.7 71.04
Measurement
with adjust. 588.4 78.24
CCCL 0.610 0.515 933.0 101.68
Case (a) 0.534 0.530 421.4 53.09
Case (b) 0.352 0.353 502.4 88.60
EDUNE
Case (c) 0.595 0.599 374.0 39.42
Case (d) 0.345 0.348 492.1 69.10
Case (a) 0.531 0.537 340.1 29.48
Case (b) 0.214 0.231 496.3 60.12
CROSS Case (c) 0.730 0.718 466.9 39.29
Case (d) 0.595 0.586 671.2 79.63
SBEACH( version 2.0) 0.936 0.935 173.5 13.71
SBEACH( version 3.0 ) 0.526 0.527 319.80 41.61
Table 6. The predicted residuals, eroded volumes and retreat for the beach at 103rd Street.
Residual eroded vol. retreat at 10 ft
Model Case
w/o adjust. with adjust. ft3 / ft contour ( ft)
w/o adjust. 456.4 44.60
Measurement
with adjust. 672.8 67.85
CCCL 2.233 1.499 1314.6 127.70
Case (a) 0.548 0.413 575.8 65.75
Case (b) 0.541 0.419 617.0 76.41
EDUNE
Case (c) 0.532 0.433 527.9 50.21
Case (d) 0.521 0.409 614.3 72.97
Case (a) 0.436 0.374 505.3 41.78
Case (b) 0.376 0.303 653.3 70.29
CROSS Case (c) 0.654 0.478 695.3 55.85
Case (d) 0.783 0.543 907.0 94.05
SBEACH (version 2.0 ) 0.596 0.590 209.2 23.07
SBEACH (version 3.0 ) 0.510 0.433 359..0 34.80
Table 7. The predicted residuals, eroded volumes and retreat for the beach at 124th Street.
Residual eroded vol. retreat at 10 ft
Model Case
w/o adjust. with adjust, ft3 / ft contour ( ft)
w/o adjust. 431.4 33.17
Measurement
with adjust. 497.0 39.09
CCCL 3.131 2.821 1432.5 104.00
Case (a) 1.000 0.968 477.3 48.51
Case (b) 0.740 0.700 543.4 56.32
EDUNE
Case (c) 1.010 1.004 420.3 32.96
Case (d) 0.698 0.670 532.0 53.63
Case (a) 0.889 0.882 451.4 29.64
Case (b) 0.543 0.519 607.5 57.17
CROSS Case (c) 1.700 1.630 674.8 43.58
Case (d) 1.781 1.681 940.8 80.01
SBEACH (version 2.0) 1.122 1.136 108.5 10.86
SBEACH (version 3.0) 0.802 0.805 180.2 15.96
Table 8. The residuals averaged over seven profiles.
Residual
Model Case
w/o adjust. with adjust.
CCCL 1.685 1.408
Case (a) 0.843 0.793
Case (b) 0.606 0.533
EDUNE
Case (c) 0.869 0.836
Case (d) 0.583 0.516
Case (a) 0.740 0.714
Case (b) 0.460 0.412
CROSS
Case (c) 1.239 1.191
Case (d) 1.170 1.097
SBEACH (version 2.0) 1.217 1.212
SBEACH ( version 3.0 ) 0.781 0.752
Table 9. Root mean square and algebraic averaged errors for eroded volumes.
w/o adjustment with adjustment
Model Case
ERRms ERRa ERRms ERRa,
CCCL 2.87 1.66 1.06 0.96
Case (a) 0.15 -0.20 0.21 -0.41
Case (b) 0.14 0.10 0.07 -0.19
EDUNE
Case (c) 0.18 -0.28 0.25 -0.47
Case (d) 0.15 0.12 0.07 -0.17
Case (a) 0.18 -0.12 0.17 -0.35
Case (b) 0.30 0.38 0.06 0.02
CROSS Case (c) 0.25 0.28 0.08 -0.05
Case (d) 0.93 0.96 0.27 0.45
SBEACH ( version 2.0 ) 0.44 -0.57 0.49 -0.68
SBEACH (version 3.0 ) 0.21 -0.26 0.23 -0.45
Table 10. Root mean square and algebraic averaged errors for retreat at the 10 foot contour.
w/o adjustment with adjustment
Model Case
ERRr, ERR,, ERR,, ERRav
CCCL 1.07 0.97 0.48 0.56
Case (a) 0.31 -0.15 0.26 -0.32
Case (b) 0.32 0.28 0.15 0.01
EDUNE
Case (c) 0.37 -0.39 0.37 -0.52
Case (d) 0.31 0.19 0.15 -0.06
Case (a) 0.42 -0.43 0.40 -0.54
Case (b) 0.37 0.30 0.18 0.03
CROSS Case (c) 0.32 -0.22 0.28 -0.38
Case (d) 0.57 0.67 0.24 0.32
SBEACH ( version 2.0 ) 0.61 -0.56 0.59 -0.65
SBEACH (version 3.0) 0.42 -0.45 0.42 -0.56
Profiles at 37th Street
0 CCCL
0
0 measured at Nov.2,91
measured at Jan.11,92
!0 ......... predicted after two storms
>n> I I I I i I
400 600
offshore distance [ft]
800
1000 1200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
Fig. 3 Comparisons of the predicted and measured profiles at 37th Street.
,> -1
(Q)
(I)
!00
200
ISBEACH (version 2.0)
.............
-2
-3C
-2
'00
200
1000
12
10- SBEACH (version 3.0)
0
10-
20-
o r > t___II lI I --
C13
S::
0
> -
(I)
cW _
800
800
-200
-200
.00
i00
200
1000
12
Profiles at 37th Street
EDUNE: Case (a)
measured at Nov.2,91
- measured at Jan.11,9;
- ......... predicted after two sto
)rms
2
rms
200
200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
800
800
U
10
20
qn I -I I I I I-
0 200
400 600
offshore distance [ft]
800
1000 1200
1000
1200
1000
10
0
-10
-20
-30
-2(
0 200
400 600
offshore distance [ft]
Fig. 3 Continued.
S10
i0
a -20
((] S
-200
-1
-c
EDUNE: Case (b)
O
0-
10 .
I'.)
AO
200
-200
10
C
O::
0
0) -
a3 _
EDUNE: Case (c)
-200
800
1000
'_1
30
DO0
00
-
-. EDUNE: Case (d)
- -I-II
-~
12
12
_)(
Profiles at 37th Street
0
10 -- measured at Nov.2,91
measured at Jan.11,92
20 ......... predicted after two storms
onI I sIII
200
0 200
0 200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
200
400 600
offshore distance [ft]
800
1000 1200
Fig. 3 Continued.
10
0
0-
>-
u_
CROSS: Case (a)
-200
-200
1000
t-
3
0-
-r
ci)
1200
CROSS: Case (b)
0-
0-
0-
2n
800
800
800
1000
- CROSS: Case (c)
I I I I I
-,
200
10
0
-10
-20
-30
-2(
S10
I- 0
> -10
_ -20
1000
12
SCROSS: Case (d)
-OU
-200
II A I I--
12
00
00
i (
><
00
Profiles at 45th Street
)- CCCL
S_--- measured at Nov.2,91 '
measured at Jan.11,92 s
) ......... predicted after two storms
0 200
400 600
offshore distance [ft]
800
1000 1200
200
400 600
offshore distance [ft]
0
10L
20-
Or .I 1-
0 200
400 600
offshore distance [ft]
Fig. 4 Comparisons of the predicted and measured profiles at 45th Street.
->30
-2C
10
C 0
i-i10
_ -20
SBEACH (version 2.0)
on'
-ou
-200
800
10
1000
1200
C::
a:;
a:' -
SBEACH (version 3.0)
-200
800
1000
1200
)0
or3
Profiles at 45th Street
' 10
S0
> -10
a -20
0 200
0 200
0 200
10
0
-10
-20
-30
-2
10
0
-10
-20
-30
-2
10
0
-10
-20
-30
-2
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
Fig. 4 Continued.
EDUNE: Case (a)
measured at Nov.2,91' -
- measured atJan.11,92
- ......... predicted after two storms
EDUNE: Case (b)
1000
12
-CI I
-200
0 200
1000
EDUNE: Case (c)
124
800
800
800
800
00
00
00
00
1000
EDUNE: Case (d)
12(
1000
12(
00
00
00
)
)
(
Profiles at 45th Street
200
0 200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
10
0
-10
-20
-30
-2(
0 200
400 600
offshore distance [ft]
Fig. 4 Continued.
" 10
. 0
> -10-
o -20
-30
-200
CROSS: Case (a)
----- measured at Nov.2,91 :
- measured at Jan.11,92
......... predicted after two storms
10 CROSS: Case (b)
0
10 -
20
_ 0 I I I I I I
C
0
ciz
D-
800
800
-200
1000
1000
1200
1200
1200
CROSS: Case (d)
800
1000
1200
I
ii
>
00
Profiles at 56th Street
---- ---- i ---- i ---- --- T-- --- -- --
)- CCCL
S, measured at Nov.2,91
measured at Jan.11,92
) ......... predicted after two storms
0 200
0 200
0 200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
800
800
800
Fig. 5 Comparisons of the predicted and measured profiles at 56th Street.
.00
1000
12'
SBEACH (version 2.0)
g'c
a' -2C
-3C
-2
-30
-2(
-200
-200
1000
121
00
30
DO0
SBEACH (version 3.0)
1000
121
O0
3n
Profiles at 56th Street
I I I I I I
0 EDUNE: Case (a)
0
-- measured at Nov.2,91 .
- measured at Jan.11,92
.0 ......... predicted after two storms
!0 1 1 1 1 ---
200 0 200 400 600 800 1000 12
offshore distance [ft]
0 200
400 600
offshore distance [ft]
800
1000 1200
0 200
400 600
offshore distance [ft]
0 200
400 600
offshore distance [ft]
800
1000 1200
Fig. 5 Continued.
C-
>-1
0
C
c
-3
""-
EDUNE: Case (b)
10
g 10
S10
D -20
-30
-2(
00
10
0
-10
-20
-30
-2(
EDUNE: Case (c)
800
1000
EDUNE: Case (d)
10
0
-10
-20
-30
-2(
1200
00
00
00
Profiles at 56th Street
10- measured at Nov.2,91
measured at Jan.11,92
20 ......... predicted after two storms
ni ii i i i
200
200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
0
10-
20
Ln iii I Ii
200
400 600
offshore distance [ft]
800
1000 1200
0 200 400 600 800 1000
offshore distance [ft]
1200
Fig. 5 Continued.
10
0
ta
>-
_,
CD
CROSS: Case (a)
I I I I I(b)
- CROSS: Case (b)
1000
12
-2(
S10
I0 0
>-10
a -20
-30
-2(
10
800
800
00
00
1000
0
a,-
12
I I
CROSS: Case (c)
-\f
-200
10
0 0-
> -10 -
, -20
-30
-200
00
00
Profiles at 63rd Street
CCCL
Measured at Nov.2,91 -' .
-- measured at Jan.11,92 .-
) ......... predicted after two storms
i i I i i-i
200
400 600
offshore distance [ft]
800
1000 1200
SBEACH (version 2.0)
_n lI I
200
400 600
offshore distance [ft]
800
1000
1200
0 200
400 600
offshore distance [ft]
Fig. 6 Comparisons of the predicted and measured profiles at 63rd Street.
S10C
Sc
> -10
-2C
-3C
-2
_00
" 10
0 0
> -10
_ -20
-200
0 "- SBEACH (version 3.0)
0 -----........ .. 2--------.---.
0
10 IIII
0-
>o-n- ^ -- -
1
0
> -1
0-2
__q
-200
800
1000
1200
I
...
--
Profiles at 63rd Street
EDUNE: Case (a)
- -- measured at Nov.2,91
- measured at Jan.11,92
- ......... predicted after two storms
200
200
200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
0 -" .
-10
20-
o n __ I I I I I I
0 200
400 600
offshore distance [ft]
800
800
800
800
1000
1000
1000
1000
Fig. 6 Continued.
K
10
0 0
> -10
a20
a) -20
~4Ifl
-200
' 10
0- 0
> -10
o -20
I I I I I I
- EDUNE: Case (b)
'e- l*
-200
-200
0 --EDUNE: Case (c)
0-
0-
0-
In*^
S1
0
a,-
-200
1200
1200
1200
1200
10
O
0 -
O
EDUNE: Case (d)
-200
-200
I
f
Profiles at 63rd Street
- --- CROSS: Case (a)
Measured at Nov.2,91
-- measured at Jan.11,92
) ......... predicted after two storms
I II
200
400 600
offshore distance [ft]
800
1000
1200
U
10
20
ra _____ I ________________ I ----- I ----------
200
200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
800
800
1000 1200
1000
1200
-200
0 200
400 600
offshore distance [ft]
Fig. 6 Continued.
g 1C
Sc
.i
) -
(D-2C
oIr
-200
10
U)-
CROSS: Case (b)
-oU
-200
g 10
-0
-20
- CROSS: Case (c)
....
-.....
In I I I II I
-200
-200
C~
0
U)
10 -- CROSS: Case (d)
O
10 -. .
20
>o I --II-i
800
1000
1200
_Q
Profiles at 74th Street
) CCCL
) measured at Nov.2,91
-measured at Jan.11,92
) ........ predicted after two storms
" I I I -I I I
0 200
>-I
a' -2C
-3C
-2
. I0
>1c
a,
-_ 2C
-3C
-2
1 CC
C
> -1c
-r-2C
_3C
_4
ic
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
800
800
800
Fig. 7 Comparisons of the predicted and measured profiles at 74th Street.
1000
12(
0 200
\ SBEACH (version 2.0)
.. .. ... .
1000
SBEACH (version 3.0)
. . .
12(
30
30
30
1000
124
00
00
30
0 200
Profiles at 74th Street
)- EDUNE: Case (a)
S----- measured at Nov.2,91 .
measured at Jan.11,92 s
) ......... predicted after two storms .-- -......
I I I l I I
200
Sc
-13C
-20
c
-2C
-3C
-2
-12
400 600
offshore distance [ft]
400 600
offshore distance [ft]
1000
800
800
0
10-
2 0 ............
,nr" II I I III I
200
400 600
offshore distance [ft]
0o '.---. ---
0
10
20 ........
h Q-llI l I
0 200
400 600
offshore distance [ft]
800
800
1000
1000
1000
Fig. 7 Continued.
200
10
12
- EDUNE: Case (b)
_............
00
00
0
)-
12
EDUNE: Case (c)
-ov
-200
10
Ct
a)
a-)
O_
I I
EDUNE: Case (d)
-200
1200
1200
-
30
30
;
_!(
!_(
Profiles at 74th Street
.. CROSS: Case (a)
-----measured at Nov.2,91
measured at Jan.11,92 :_ -
- ......... predicted after two storms
II I I I I
0 200
10
0
10
20
30
-2(
10
0
10
20
30
-2(
400
600
offshore distance [ft]
'C
a)
_a
a-
>-
Cz
(D
>-
cu-
0
U)
) -
1000
800
800
121
1000
12
10 -- CROSS: Case (c)
0
10-
20
nI I I I I I
200
400 600
offshore distance [ft]
800
1000
0 200 400 600 800 1000
offshore distance [ft]
12
00
00
00
1200
Fig. 7 Continued.
0 200
I I I I I I
400 600
offshore distance [ft]
-2(
10
0
10
20
30
-2
DO
00
30
30
I,
Profiles at 103rd Street
) ~ CCCL
S- measured at Nov.2,91 '
r measured at Jan.11,92 --...
S- ......... predicted after two storms
"I' I I I '
0 200
400 600
offshore distance [ft]
800
200
400 600
offshore distance [ft]
800
1000 1200
-- SBEACH (version 3.0)
7 .o
200
400 600
offshore distance [ft]
800
1000
1200
Fig. 8 Comparisons of the predicted and measured profiles at 103rd Street.
S10
> -10
> 1
) -2C
-3C
-2
!00
1000
1200
) SBEACH (version 2.0)
- ----i- i -i -
.00
S10C
0 c
>-1c
,2
) -2C
-3C
-2
S10
0 0
) -10
( -20
-200
?n I I I I
Profiles at 103rd Street
SEDUNE: Case (a)
----- measured at Nov.2,91
- measured at Jan.11,92
......... predicted after two storms
____ I ___ I ___ I ________ I ---- I ---
0 200
0 200
400 600
offshore distance [ft]
400
600
offshore distance [ft]
400 600
offshore distance [ft]
800
1000 1200
-200
0 200
400 600
offshore distance [ft]
Fig. 8 Continued.
-30
-2(
--O
-200
1000
121
800
800
DO
00
0 EDUNE: Case (c)
0
0
o-
1000
o
u) -2
12
200
-200
" 10
10
1) -20
-20
EDUNE: Case (d)
N5
-I
800
1000
1200
EDUNE: Case (b)
~ni I I I I I
00
o0
_
Profiles at 103rd Street
SCROSS: Case (a)
- measured at Nov.2,91 .
- measured at Jan.11,92 ..
. ......... predicted after two storms
I I II I
0 200
0 200
,ni I
200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
400 600
offshore distance [ft]
-10 -
-20
/o n I I I I I I
0 200
400 600
offshore distance [ft]
800
1000 1200
Fig. 8 Continued.
1000
- ~ CROSS: Case (b)
I I I I I I
12
-30
-2(
S10
I 0
S-10
o -20
-30
-2(
- 10
I0 0
> -10
a)
o -20
00
00
800
800
800
= CROSS: Case (c)
..... .
12
1000
1000
-200
10
t--
O_
1200
CROSS: Case (d)
-200
30
)0
m.
Profiles at 124th Street
CCCL
------ measured at Nov.2,91 '
measured at Jan.11,92
- ......... predicted after two storms
200
400 600
offshore distance [ft]
800
'S..I
U
20
200
400 600
offshore distance [ft]
SBEACH (version 2.0)
800
1000 1200
I I
SBEACH (version 3.0)
0
10-
2 0 ~
0 200
400 600
offshore distance [ft]
800
1000
1200
Fig. 9 Comparisons of the predicted and measured profiles at 124th Street.
' 10
'0 0
as
> -10
-20
-200
10
1000
1200
0
a,-
10
C
a,-
-200
"' '
i B
I
m
m
Profiles at 124th Street
0 EDUNE: Case (a)
0
0 measured at Nov.2,91
-.- measured at Jan.11,92 .
.0 ......... predicted after two storms
0I I I I I I
0 200
200
400
600
offshore distance [ft]
400 600
offshore distance [ft]
200
400 600
offshore distance [ft]
800
1000 1200
0 200 400 600 800 1000
offshore distance [ft]
1200
Fig. 9 Continued.
0
S-1
U,
o-2
-3
-
200
-200
-'' 10
0 0
> -10
a-
0-_20
OA
-200
-200
800
1000
1200
SEDUNE: Case (b)
__I I I I_
C
cu
0
4-.
O
.m
oD_
800
1000
10 EDUNE: Case (c)
0
10
20
,fn III II
1200
-200
-10-
-20-
-30
-200
Profiles at 124th Street
SCROSS: Case (a)
-- --- measured at Nov.2,91 '-..
measured at Jan.11,92
- ......... predicted after two storms
0 200
0 200
400 600
offshore distance [ft]
400 600
offshore distance [ft]
800
800
12
1000
1000
-200 0 200 400 600 800 1000
offshore distance [ft]
10
0
-10
-20
-30
-2(
1200
1200
0- CROSS: Case (d)
0
0
0
0 --A---
0 200
400 600
offshore distance [ft]
Fig. 9 Continued.
00
" 10
0 0
> -10
S-20
-30
-2(
I CROSS: Case (b)
I I I I I
0
c1-
CU
(D -2
-3
800
1000
1200
00
00
200
REFERENCES
Chiu, T.Y. and Dean, R. G. 1984. "Methodology on coastal construction control line establishment"
Tech. and Design Memorandum 84-6, Beaches and Shore Resource Center, Florida State University,
Tallahassee, FL.
Chiu, T.Y. and Dean, R. G. 1986. "Additional comparisons between computed and measured
erosion by hurricanes" Tech. Report Beaches and Shore Resource Center, Florida State University,
Tallahassee, FL.
Dean, R.G. and Zheng, J. 1994. "Cross-shore sediment transport relationships." Tech. Report
UFL/COEL-94/018, Dept. of Coastal and Ocean. Eng., University of Florida, Gainesville, FL.
Jensen, R.E. and Garcia, A. 1993. "Wind, wave and water level assessment for the January 4, 1992
storm erosion at Ocean City, Maryland" Shore and Beach, Jan. 1993.
Kraus, N.C. and Wise R.A. 1993. "Simulation of January 4, 1992 storm erosion at Ocean City,
Maryland" Shore and Beach, Jan. 1993.
Kriebel, D.L. 1989. "Users manual for dune erosion model EDUNE" .
Kriebel, D.L. 1990. "Advances in numerical modeling of dune erosion" 22nd International
conference on Coastal Engineering, Delft, The Netherlands, PP.2304-2317.
Larson, M. and Kraus, N.C. 1989. "SBEACH: Numerical model for simulating storm-induced beach
change, Report 1: Theory and model foundation" Tech. Report CERC 89-9, CERC, US Army WES,
Vicksburg, MS.
Larson, M. and Kraus N.C. and Byrnes M.R. 1989. "SBEACH : Numerical model for simulating
storm-induced beach change, Report 2: Numerical formulation and model tests" Tech. Report CERC
89-9, CERC, US Army WES, Vicksburg, MS.
Stauble, D.K., Garcia A.W. and Kraus N.C. 1993. "Beach nourishment project response and design
evaluation: Ocean City, Maryland. Report 1, 1988- 1992." Tech. Report CERC 93-13, CERC, US
Army WES, Vicksburg, MS.
Zheng, J. and Dean, R. G. 1995. "Comparisons of erosion models for January 4, 1992, storm at
Ocean City, Maryland" Tech. Report UFL/COEL-95/002, Dept. of Coastal and Ocean. Eng.,
University of Florida, Gainesville, FL.
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