Table 2 Results of the numerical model validation of the physical model run D3 (test series XB1).

D50, sediment size; K, hydraulic conductivity; φ, sediment transport phase angle; BSS, Brier skill score (goodness of fit; cf. Eq. 4); Δzcrest, difference between modeled and measured island crest elevation; Δxcrest, difference between modeled and measured island crest position. For all model runs, Hs = 4 m, Tp = 9.9 s, hreef = 3 m, and Ttest = 50 hours. “X” denotes that the island was destroyed during the simulation. Bold values for BSS, Δzcrest, and Δxcrest represent the best performance of the numerical model in each of the groups of model runs. Positive values for Δzcrest and Δxcrest mean that the modeled crest is higher and further landward, respectively.

Test seriesD50 (mm)K (m s−1)φ (°)BSS (−)Δzcrest (m)Δxcrest (m)
Sensitivity to sediment transport phase angle φ
XB1_06_005_2560.00525XXX
XB1_06_005_2660.00527XXX
XB1_06_005_2960.005290.790.0614.0
XB1_06_005_3060.005300.890.258.2
XB1_06_005_3160.005310.860.404.9
XB1_06_005_3360.005330.740.600.4
XB1_06_005_3560.005350.630.74−1.9
Sensitivity to hydraulic conductivity K
XB1_10_000_25100.000250.53−0.8321.8
XB1_10_005_25100.005250.68−0.5617.0
XB1_10_010_25100.010250.830.106.2
XB1_10_020_25100.020250.660.420.3
XB1_10_030_25100.030250.500.54−2.7
XB1_10_040_25100.040250.420.63−4.3
XB1_10_050_25100.050250.360.71−5.9
Sensitivity to sediment size D50
XB1_06_005_2560.00525XXX
XB1_08_005_2580.00525XXX
XB1_10_005_25100.005250.68−0.5617.0
XB1_12_005_25120.005250.88−0.209.7
XB1_14_005_25140.005250.770.082.1
Sensitivity to sediment size D50 and hydraulic conductivity K
XB1_06_010_2560.01025XXX
XB1_07_020_2570.020250.830.318.3
XB1_08_030_2580.030250.590.520.6
XB1_10_050_25100.050250.360.71−5.9
XB1_12_070_25120.070250.210.86−7.3
XB1_15_000_25150.000250.84−0.173.5
XB1_15_050_25150.050250.240.76−7.4