Preserving high-resolution surface and rainfall data in operational-scale basin hydrology: a fully-distributed physically-based approach

This study presents various aspects of the continuous simulation capabilities of a fully-distributed, triangulated irregular network (TIN) hydrologic model. The TIN-based Real-time Integrated Basin Simulator (tRIBS) is calibrated and verified for the Baron Fork at Eldon, Illinois River at Watts, and Blue River at Blue over the period 1993–2000. Computational effort is significantly reduced by simulating complex watersheds using a multiple resolution mesh to represent terrain. Model performance is assessed by comparing streamflow predictions to observations at the basin outlet and interior gauging stations. In addition, simulation results describing the distributed basin response to atmospheric forcing are discussed, including the spatial and temporal variability of runoff, surface soil moisture, evaporative flux, and groundwater table position. By modeling the land-surface water and energy states and fluxes over the computational domain in an efficient manner, the potential for utilizing fully-distributed models at the scales of operational hydrologic forecasting is realized. Through the spatially-explicit approach, high-resolution remote sensing data describing surface properties, topography, rainfall, and soil moisture can be integrated directly into a predictive hydrologic model. A greater degree of physical interpretation of hydrological estimation can thus be added to existing methods of operational forecasting.