HR: 1330h
AN: H12B-0969    [PDF]
TI: Assessing Hydrologic Similarity of Watersheds by Analyzing Geometric Patterns in Streamflow Time Series
AU: * Teegavarapu, R
EM: ramesh@engr.uky.edu
AF: University of Kentucky, 161 Oliver Raymond Hall Departmet of Civil Engineering, Lexington, KY 40506 United States
AU: Tangirala, A
EM: aktang@uky.edu
AF: University of Kentucky, 161 Oliver Raymond Hall Departmet of Civil Engineering, Lexington, KY 40506 United States
AU: Ormsbee, L
EM: lormsbee@engr.uky.edu
AF: University of Kentucky, 161 Oliver Raymond Hall Departmet of Civil Engineering, Lexington, KY 40506 United States
AB: The concept of hydrologic similarity has been used in the past in the field of watershed hydrology to identify points or units in watersheds to assess their similar responses for a specific rainfall event. The similarity idea has also helped in identifying hydrologic response units (HRU) and improved representation of hydrologic processes in distributed hydrologic models. In the present study hydrologic similarity at a watershed scale is evaluated by using observed hydrologic time series data. The process involves exploring patterns in data time series and is almost similar to pattern recognition task in which a specific structure is searched in data items or observations. The motivation for evaluating these patterns is derived from the fact that observed data carry information either about the process generating them or the phenomenon they represent. Therefore the main objective of this study is to explore the possibility of establishing similarity in the hydrologic response of the watersheds based on geometrical patterns identified from observed streamflow time series. If the distribution of geometric patterns is similar, then a hydrologic similarity can be assumed as the response of the watershed is reflected in the observed streamflow values. Once a hydrologic similarity between any two watersheds is established using the similarity in the geometric patterns, then one or more of the several watershed physical properties (landuse, soils or topography) can be used to confirm the hypothesized similarity. The concept of establishing hydrological similarity using streamflow time series is tested by analyzing historical streamflow data from several USGS gaging stations in the state of Kentucky. The streamflow data is processed using a data-sorting program developed specifically for analyzing geometric patterns. Digital Elevation Models (DEMs) are used to delineate watersheds using the location of the gaging stations as outlets of the watersheds. Similarity in Land use/Land cover information is used as one of tests to confirm the possible existence of hydrologic similarity. If hydrological similarity is established based on the patterns in streamflow time series, transferability of streamflow prediction approaches can be evaluated.
DE: 1871 Surface water quality
SC: Hydrology [H]
MN: 2003 Fall Meeting