HR: 1340h
AN: H13C-0419    [Abstracts]
TI: A Quantitative and Objective Procedure for Evaluation of Distributed Hydrologic and Hydrometeorological Models
AU: * Li, S
EM: shujun.li@usu.edu
AF: Civil and Environmental Engineering and Utah Water Research Laboratory, Utah State University, 4110 Old Main Hill, Logan, UT 84322-4110 United States
AU: Bastidas, L A
EM: luis.bastidas@usu.edu
AF: Civil and Environmental Engineering and Utah Water Research Laboratory, Utah State University, 4110 Old Main Hill, Logan, UT 84322-4110 United States
AB: Better spatial pattern representation of hydrological variables is one of the important targets of distributed hydrologic and hydrometeorological models at basin scale. In this paper, we introduce a set theory-based similarity measure - the Hausdorff Norm (HN), for a quantitative evaluation of distributed fields of hydro-meteorological variables against observations. The procedure can be used for the evaluation of individual fields or for the evaluation of several fields simultaneously. The procedure is not limited to snapshots as a sequence of several distributed fields in time can also be evaluated. The procedure is tested using the noah LSM over a semi-arid watershed, the San Pedro River basin in Arizona. The noah model is run using three different uniform resolution grids (1, 4, 12 km) and a multiple resolution grid scheme (1 km to 12 km) defined by the degree of land surface and sub-surface characteristics of this watershed. The model is driven in offline fashion with hourly forcing data remapped from the NLDAS. Surface characteristics like vegetation, soil and topography are remapped from a fine resolution uniform grid (1km). An evaluation of the influence of vegetation parameter estimation is also carried out. Vegetation parameters were estimated at multiple representative sites in the San Pedro basin using a multi-objective framework. All the evaluations are carried out for July 2003 (a period of strong monsoon influence). The ground surface temperature fields are contrasted to those obtained from the MODIS-AQUA instrument. For the simultaneous multiple field evaluation/comparison we used the results from the NLDAS Mosaic model. For the simultaneous multiple field evaluation/comparison of the different distributed noah model resolutions and the evaluation of the influence of the parameter estimation procedures a 1 km noah model resolution output using the non-optimized parameter values (model default) is the benchmark. These extensive and comprehensive tests have shown the extreme versatility and power of the HN as a tool for evaluation and comparison of distributed model performances at different spatial scales. The HN provides with a quantitative measure of the model goodness.
DE: 9820 Techniques applicable in three or more fields
DE: 3322 Land/atmosphere interactions
DE: 1833 Hydroclimatology
DE: 1640 Remote sensing
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting