10
0.550 0.600
0.650 0.700
0.750 0.800
0.850 0.900
0.950 1.000
-0.2251 -0.2375
-0.2485 -0.2582
-0.2667 -0.2739
-0.2801 -0.2852
-0.2895 -0.2929
0.6129 0.5879
0.5879 0.5631
0.5387 0.5148
0.4914 0.4886
0.4466 0.4254
1.2513 1.2428
1.2226 1.2011
1.1784 1.1548
1.1306 1.1060
1.0810 1.0560
1.8931 1.8916
1.8866 1.8786
1.8577 1.8543
1.8388 1.8212
1.8021 1.7815
2.7615 2.7974
2.8279 2.8532
2.8735 2.8891
2.9002 2.9071
2.9102 2.9098
3.4488 3.5241
3.5930 3.6568
3.7118 3.7617
3.8056 3.8437
3.8762 3.9036
2.2.2.3. Sebaran Log Pearson III
Untuk menghitung banjir rencana, the Hidrologi Committee of the Water Resources Council, USA menganjurkan, pertama kali mentransformasikan data ke
harga-harga logaritmanya, kemudian menghitung parameter-parameter statistiknya. Rumus Umum yang dipakai adalah :
LnX
T
= LnX
r
+ K. S.lnX Dimana :
LnX
T
= Logaritma natural dari curah hujan dalam kala ulang T tahun LnX
r
= Harga rata-rata =
n x
n i
i
∑
=1
ln
K = Faktor frekuensi untuk sebaran log Pearson III
S.lnX = Standart deviasi =
1 ln
ln
1 3
− −
∑
=
n X
X
n i
r i
Tabel 2.4. Faktor K untuk Cs0
Asimetri
Periode Ulang
1.0101 1.0526
1.1111 1.250
2 5
10 25
50 100
200
3.0 2.9
2.8 2.7
2.6 2.5
2.4 2.3
-0.667 -0.690
-0.714 -0.769
-0.799 -0.812
-0.867 -0.905
-0.665 -0.688
-0.711 -0.736
-0.762 -0.790
-0.819 -0.850
-0.666 -0.681
-0.702 -0.725
-0.747 -0.771
-0.798 -0.819
-0.636 -0.651
-0.666 -0.681
-0.696 -0.711
-0.725 -0.739
-0.396 -0.390
-0.384 -0.376
-0.368 -0.360
-0.351 -0.341
0.420 0.440
0.460 0.479
0.499 0.518
0.537 0.555
1.180 1.195
1.210 1.224
1.236 1.250
1.262 1.274
2.278 2.277
2.275 2.272
2.267 2.262
2.256 2.248
3.152 3.134
3.114 3.093
3.072 3.048
3.029 2.997
4.054 4.012
3.973 3.932
3.889 3.845
3.800 3.753
4.976 4.909
4.847 4.783
4.718 4.652
4.584 4.515
11
2.2 2.1
2.0 1.9
1.8 1.7
1.6 1.5
1.4 1.3
1.2 1.1
1.0 0.9
0.8 0.7
0.6 0.5
0.4 0.3
0.2 0.1
-0.946 -0.990
-1.037 -1.037
-1.087 -1.140
-1.197 -1.256
-1.318 -1.383
-1.449 -1.518
-1.588 -1.660
-1.733 -1.806
-1.880 -1.955
-2.029 -2.104
-2.176 -2.252
-2.326 -0.882
-0.914 -0.949
-0.984 -1.020
-1.056 -1.093
-1.131 -1.163
-1.206 -1.243
-1.280 -1.317
-1.353 -1.388
-1.423 -1.455
-1.491 -1.524
-1.555 -1.586
-1.616 -1.645
-0.844 -0.869
-0.895 -0.920
-0.945 -0.970
-0.994 -1.018
-1.041 -1.064
-1.086 -1.107
-1.128 -1.147
-1.166 -1.183
-1.209 -1.216
-1.231 -1.245
-1.258 -1.270
-1.282 -0.752
-0.785 -0.777
-0.788 -0.799
-0.808 -0.817
-0.825 -0.832
-0.838 -0.844
-0.848 -0.852
-0.854 -0.856
-0.857 -0.857
-0.856 -0.855
-0.853 -0.850
-0.846 -0.852
-0.330 -0.319
-0.307 -0.294
-0.282 -0.268
-0.254 -0.240
-0.225 -0.210
-0.195 -0.180
-0.164 -0.148
-0.132 -0.116
-0.099 -0.083
-0.066 -0.050
-0.033 -0.017
0.574 0.592
0.609 0.627
0.643 0.660
0.675 0.690
0.705 0.719
0.732 0.745
0.758 0.769
0.780 0.790
0.800 0.808
0.816 0.824
0.830 0.836
0.842 1.284
1.294 1.302
1.310 1.318
1.324 1.329
1.333 1.337
1.339 1.340
1.341 1.340
1.339 1.336
1.333 1.328
1.323 1.317
1.309 1.301
1.292 1.282
2.240 2.230
2.219 2.207
2.193 2.179
2.163 2.146
2.128 2.108
2.087 20.66
2.043 2.019
1.993 1.967
1.939 1.910
1.880 1.849
1.818 1.785
1.751 2.970
2.942 2.912
2.881 2.848
2.815 2.780
2.745 2.706
2.666 2.626
2.585 2.542
2.498 2.453
2.407 2.359
2.311 2.261
2.211 2.159
2.107 2.054
3.705 3.656
3.605 3.553
3.499 3.444
3.386 3.330
3.271 3.211
3.149 3.087
3.022 2.957
2.891 2.874
2.755 2.686
2.615 2.544
2.472 2.400
2.326 4.454
4.372 4.298
4.224 4.147
4.065 3.990
3.910 3.721
3.765 3.661
3.575 3.489
3.401 3.312
3.223 3.132
3.041 2.949
2.856 2.763
2.670 2.576
Tabel 2.5. Faktor K untuk Cs0
Asime tri
Periode Ulang
1.0101 1.0526
1.1111 1.250
2 5
10 25
50 100
200
-0.1 -0.2
-0.3 -0.4
-0.5 -0.6
-0.7 -0.8
-0.9 -1.0
-1.1 -1.2
-1.3 -1.4
-1.5 -1.6
-1.7 -1.8
-1.9 -2.326
-2.400 -2.472
-2.544 -2.615
-2.686 -2.755
-2.824 -2.891
-2.957 -3.022
-3.087 -3.149
-3.211 -3.271
-3.330 -3.388
-3.444 -3.499
-3.553 -1.645
-1.673 -1.700
-1.726 -1.750
-1.774 -1.797
-1.819 -1.839
-1.858 -1.877
-1.894 -1.910
-1.925 -1.938
-1.951 -1.962
-1.972 -1.981
-1.989 -1.282
-1.292 -1.301
-1.309 -1.317
-1.323 -1.328
-1.333 -1.336
-1.339 -1.340
-1.341 -1.340
-1.339 -1.337
-1.333 -1.329
-1.324 -1.318
-1.310 -0.852
-0.836 -0.830
-0.824 -0.816
-0.808 -0.800
-0.790 -0.780
-0.769 -0.738
-0.745 -0.732
-0.719 -0.705
-0.690 -0.675
-0.660 -0.643
-0.621 0.017
0.033 0.050
0.066 0.083
0.099 0.116
0.132 0.148
0.164 0.180
0.195 0.210
0.225 0.240
0.254 0.268
0.282 0.294
0.842 0.846
0.850 0.853
0.855 0.856
0.857 0.857
0.856 0.854
0.852 0.848
0.844 0.838
0.832 0.825
0.817 0.808
0.799 0.788
1.282 1.270
1.258 1.245
1.231 1.216
1.200 1.183
1.166 1.147
1.128 1.107
1.086 1.064
1.041 1.018
0.994 0.970
0.945 0.920
1.751 1.716
1.680 1.643
1.606 1.567
1.528 1.488
1.448 1.407
1.366 1.324
1.282 1.240
1.198 1.157
1.116 1.075
1.035 0.996
2.054 2.000
1.945 1.890
1.814 1.777
1.720 1.663
1.606 1.549
1.492 1.435
1.379 1.324
1.282 1.240
1.166 1.116
1.069 1.023
2.326 2.252
2.178 2.104
2.029 1.955
1.880 1.806
1.733 1.660
1.588 1.518
1.449 1.383
1.318 1.256
1.197 1.140
1.087 1.037
2.576 2.482
2.388 2.294
2.201 2.108
2.016 1.926
1.837 1.748
1.664 1.586
1.501 1.484
1.351 1.282
1.216 1.166
1.096 1.044
12
-2.0 -2.1
-2.2 -2.3
-2.4 -2.5
-2.6 -2.7
-2.8 -2.9
-3.0 -3.605
-3.656 -3.705
-3.753 -3.800
-3.845 -3.889
-3.932 -3.973
-4.013 -4.051
-1.996 -2.001
-2.006 -2.009
-2.011 -2.012
-2.013 -2.012
-2.010 -2.007
-2.003 -1.302
-1.294 -1.284
-1.274 -1.262
-1.250 -1.238
-1.224 -1.210
-1.195 -1.180
-0.609 -0.592
-0.574 -0.555
-0.537 -0.518
-0.499 -0.479
-0.460 -0.440
-0.440 0.307
0.319 0.330
0.341 0.351
0.360 0.368
0.375 0.384
0.330 0.390
0.777 0.765
0.752 0.739
0.723 0.711
0.696 0.681
0.666 0.651
0.636 0.895
0.869 0.844
0.819 0.795
0.771 0.747
0.724 0.702
0.681 0.666
0.959 0.923
0.888 0.855
0.823 0.793
0.764 0.738
0.712 0.683
0.666 0.980
0.939 0.900
0.864 0.830
0.798 0.768
0.740 0.714
0.689 0.666
0.990 0.924
0.905 0.867
0.832 0.799
0.768 0.740
0.714 0.690
0.667 0.993
0.949 0.907
0.869 0.833
0.800 0.769
0.741 0.714
0.690 0.667
2.2.2.4 Metode Gumbel Tipe I
