 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
|
|
|
Parameter Sensitivity in Hydrologic Modelingby Tanya Nicole Hoogerwerf and David R. Maidment, Ph.D. ABSTRACT The computation of discharge from a watershed depends on the lag time between rainfall and runoff, while in turn the lag time depends on watershed parameters, such as length of the longest flow path, watershed slope, and the SCS curve number describing the effects of land use and soils. This research explores the variation in lag time and discharge resulting from traditional and automated methods of calculating hydrologic parameters. Four levels of extracting hydrologic parameters are explored: (1) measurement from paper maps, (2) on-screen extraction from raster maps, (3) using GIS and two different resolutions of grid-based digital elevation models (DEMs), and (4) using a triangulated irregular network (TIN). Results show that variations in watershed area and curve number most directly impact the computed discharge, while variations in slope and flow path length are relatively insignificant. The highlighted links that follow are connected to Adobe pdf files of the corresponding material. To view them you must have the Adobe Acrobat Reader 3.0. View the Report...(4995 KB)
These materials may be used for study, research, and education, but please credit the authors and the Center for Research in Water Resources, The University of Texas at Austin. All commercial rights reserved. Copyright 2002 Center for Research in Water Resources. |
|
|
|
