DISTRIBUTED HYDROLOGIC MODELING USING GIS
1 Introduction to Physics-Based Distributed Hydrology 1 11 Introduction 1 12 Model Classification 3 13 Geospatial Data for Hydrology 9 14 Surface Generation 10 15 Spatial Resolution and Information Content 11 16 Infiltration 11 17 Hydraulic Roughness 12 18 Watersheds and Drainage Networks 13 19 Distributed Precipitation Estimation 13 110 Surface Runoff Model Formulation 14 111 Distributed Model Calibration 16 112 Case Studies in Distributed Hydrology 16 113 Vflo®—Software for Distributed Hydrology 17 114 Summary 17 References 18 2 Geospatial Data for Hydrology 21 21 Introduction 21 22 Map Scale and Spatial Detail 22 23 Georeferenced Coordinate Systems 23 24 Map Projections 25 25 Data Representation 29 251 Metadata 29 252 Topographic Representation 30 26 Watershed Delineation 35 261 Algorithms for Delineating Watersheds 36 262 Problems with Flat Areas 37 27 Soil Classification 38 28 Land Use/Cover Classification 40 29 Summary 41 References 41 3 Surface Generation 43 31 Introduction 43 32 Interpolation 44 321 Inverse Distance Weighted Interpolation 46 322 Kriging 48 323 Spline 54 33 Summary 61 References 62 4 Spatial Variability Measuring Information Content 65 41 Introduction 65 42 Information Content 71 43 Fractal Interpretation 73 44 DEM Resolution Effects 75 45 Summary 80 References 81 5 Infiltration 83 51 Introduction 83 52 Approaches to Infiltration Modeling 85 53 Green-Ampt Infiltration 89 531 Parameter Estimation 90 532 Parameter Uncertainty 94 54 Summary 96 References 97 6 Hydraulic Roughness 101 61 Introduction 101 62 Hydraulics of Surface Runoff 103 63 Watershed Applications 108 64 Summary 112 References 113 7 Watersheds and Drainage Networks 115 71 Introduction 115 72 Drainage Network Extraction 116 721 Sensitivity to Drainage Network Composition 120 722 Resolution-Dependent Effects 123 723 Constraining Drainage Direction 126 73 Summary 128 References 130 8 Distributed Precipitation Estimation 133 81 Introduction 133 82 Rain Gauge Estimation of Rainfall 133 83 Radar Estimation of Precipitation 142 831 Rainfall Drop Size Distributions 144 832 Z-R Relationships 146 833 Radar Power Differences 148 834 Radar Bias Adjustment 149 835 WSR-88D Radar Characteristics 152 836 WSR-88D Precipitation Processing Stream 154 84 Input for Hydrologic Modeling 157 85 Summary 160 References 161 9 Surface Runoff Model Formulation 165 91 Introduction 165 92 Mathematical Formulation 169 921 Numerical Solution 171 922 Grid Resolution Effects 173 93 Surface Runoff Modeling Example 173 94 Time-Dependent Solution 177 95 Rainfall Excess Determination 177 96 Subsurface Flow 179 97 Subsurface and Surface Water Balance 182 98 Summary 184 References 184 10 Distributed Model Calibration 189 101 Introduction 189 102 Calibration Approach 191 103 Distributed Model Calibration 193 1031 Parameter Adjustment 194 1032 Cost Functions 197 104 Parameter Search Algorithms 201 1041 Forward Model 202 1042 Inverse Model 202 105 Calibration Example 205 106 Summary 206 References 207 11 Case Studies in Distributed Hydrology 211 111 Introduction 211 112 Case Study I—Reservoir Inflow Forecasting 212 1121 Hydrometeorological System 214 1122 Model Parameter Adjustment 216 113 Case Study II—Urban Flood Forecasting 217 1131 Basin Characteristics 218 114 Case Study III—Climate Change Impact Assessment 220 1141 Precipitation Inputs 221 1142 Potential Evapotranspiration 221 1143 Hydrologic Modeling ‘As-If’ Climate Has Changed 222 1144 Historic Period Calibration 224 1145 Climate Change Perturbation 226 1146 Hydrologic Analysis 230 115 Summary 232 References 233 12 Vflo®—Software for Distributed Hydrology 235 121 Introduction 235 122 Building Watershed Models 238 123 Precipitation Input 238 1231 Design Storm Analysis 238 1232 Continuous Simulation 241 124 Pipes Extension 245 125 Inundation Analyst 245 126 Model Feature Summary 247 1261 Cell Types 249 1262 Network Statistics 250 1263 Channel Routing 253 1264 Baseflow 253 1265 Infiltration 254 1266 Precipitation Input Format 254 1267 Calibration 255 127 Vflo® Real-time 256 128 Data Requirements 257 129 Summary 258 References 258