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<br />TABLE 3a. . Summary of Sensitivity Analysis Resuhs, center-Peaked Temporal Rainfall Distribution: Assumed" Input
<br />
<br />Meteorological
<br />factor Values assumed for meteorological factors in sensitivity analysis
<br />(input)
<br />Lc DC DC DSC DSC USC USC DC DC DSC DSC USC use DC De DSC Dse USC use
<br /><I> 181 270 181 270 181 270 ]81 270 18] 270 181 270 181 270 181 270 181 270
<br />P, 2.5 2.5 2.5 2.5 2.5 2,5 1.0 1.0 1.0 1:0 1.0 1.0 4,0 4,0 4,0 4,0 4,0 4,0
<br />S, 50 175 100 300 100 300 50 - - - - - 50 - - - - -
<br />PMSV 23 20 22 17 22 17 22 - - - - - 23 - - - - -
<br />
<br />TABLE 3b. Results
<br />
<br />Assumed
<br />land
<br />cover PMF
<br />(input) (output)
<br />HFD Q, 174 166 160 134 ]60 13] 181 162 166 140 166 136 ]66 148 152 128 152 125
<br /> I, 6,5 6,6 6.4 5.5 6,7 6.9 6.5 - - - - - 6.5 - - - - -
<br />DHFD Q, 155 137 ]43 121 14] 112 162 143 150 127 147 117 147 130 136 115 134 106
<br /> I, 6.4 6,5 5.5 5,5 6.6 6,8 6,5 - - - - - ,6.4 - - - - -
<br />UMHFD Q, 155 138 143 119 142 114 162 ]44 149 124 148 '119 147 131 135 113 134 108
<br /> I, 604 - - - - - - - - - - - - - - - -
<br />UHFD Q, 154 136 141 115 140 112 161 142 147 120 147 117 146 129 133 109 133 106
<br /> I, 6,5 6,6 6.4 5.5 6,7 7.4 - - - - - - - - - - - -
<br />HUD Q, 136 121 125 ]04 124 100, 143 127 13l 109 131 105 128 113 117 98 117 94
<br /> I, 6.4 - - - - - - - - - - - 6.4 - - - - -
<br />
<br />Note: Variables as explained in Table 2.
<br />
<br />TABLE 4a. Summary of Sensitivity Analysis Results, late-Peaked Temporal Rainfall Distribution: Assumed Input
<br />
<br />Meteorological Values assumed for meteor~logical factors. in sensiti~ .analysis
<br />factor (input)
<br />L, ' De De Dse Dse USC use De DC Dse Dse use use DC DC Dse Dse use use
<br /><I> 181 270 181 270 181 270 181 270 181 270 181 270 181 270 181 270 181 270
<br />P, 2,5 2.5 ' 2.5 2.5 2,5 2.5 1.0 1.0 1.0 1.0 1.0 1.0 4,0 4.0 4,0 4,0 4,0 4,0
<br />S, 50 175 100 300 100 300 ,50 - - - - - 50 - - - - -
<br />PMSV 23 20 22 17 22 11 22 - - - - - 23 - - - - -
<br />
<br />TABLE 4b, ResuRs
<br />
<br />Assumed
<br />land
<br />cover PMF
<br />(input) (output)
<br />HFD Q, 166 143 162 139 147 110 172 148 169 144 153 114 158 136 155 132 140 105
<br /> I, 8,1 8,1 7.1 7,1 8,1 8,8 - - - - - '- f.---'-- - - - -
<br />DHFD Q, 146 123 143 120 128 90, 153 129 149 125 133 '94 139 117 136 113 121 86
<br /> I, 8,1 8,1 7,1 7.1 ' 8.8 ,8,8 - - - - - , - - - - - - -
<br />UMHFD Q, 154 131 148 125 135 100 161 137 155 130 142 105 146 124 140 118 128 95
<br /> I, 8,1 - - - - - - - - " - - - - - - -
<br />UHFD Q, 154 131 144 120 135 104 161 137 150 125 141 109 146 124 136 113 128 99
<br /> I, 8,1 8,1 8.1 7,1 8,1 8,8 - - - - - - - - - - ,- -
<br />HUD Q, 135 114 130 109 118 88 141 120 136 115 124 92 126 107 121 103 112 82
<br /> I, 8,1 - - - - - - - - - - - - - - - - -
<br />
<br />Note: Variables as explained in Table 2.
<br />
<br />Temporal Distribution of Rainfall
<br />
<br />The temporal rainfall distribution (early peak, center peak,
<br />or late peak) is selected with the objective ofmaximi2ing the
<br />'PMF. A significant interaction between the temporal rainfall
<br />distribution, RT and one of the factors indicates that a change
<br />in RT must be accompanied by a change ~n the interacting
<br />factor. It was noted that the interaction between temporal
<br />rainfall distribution. RT and both the stonn-center location,
<br />L, and the landcover distribution was found to be significant.
<br />While the stom center location (0, 0) yielded the largest PMF
<br />regardless of the assumed temporal rainfall distribution, the
<br />other two storm.center locations displayed the significance of
<br />the interaction between the RT and the L,. Specifically, for
<br />an Lc of (0,0), a center-peaked RT> followed by a late-peaked
<br />RT' followed by an early-peaked RT yielded the largest PMF;
<br />
<br />the largest drainage-centered concentration of rainfall cou-
<br />pled with the center-peaked Ri yields the largest estimate of '
<br />the .PMF.- For an Lc of (0, - 3.83), a late-peaked RT followed
<br />by a center-peakedR" followed by an early-peaked RTyielded
<br />the largest,PMF; the largest downstream subbasins-centered
<br />concentration of rainfall coupled with the late-peaked RT yields
<br />the largest estimate of the PMF, As for an Lc of (0, 3,83), a
<br />centered-peaked RT yielded the largest PMF; the largest up-
<br />stream su~,basins-centered concen.tration of rainfall coupled
<br />with the cenier-peaked RT yields the largest estimated PMF;
<br />the late-peaked RT is not the optimum because of the effect
<br />of Jag time), while a late-peaked RT followed by an early-
<br />peaked RT yield the largest PMF for a <l> of 181" and the
<br />reverse is true for a <l> of 27ll" (since <l> at 2700 yields less
<br />rainfall thana <l> at 181', an early-peaked RT optimized the
<br />
<br />JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING / SEPTEMBER/OCTOBER t995/ 333
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