1a.Objectives (from AD-416)
1) Apply the modified Penn State Integrated Hydrology Modeling (PIHM) system over RCEW using all available data;. 2)Selectively reduce input data to determine the minimum input forcing data required to achieve acceptable simulation accuracy;. 3)Recommend augmentation of existing measurement facilities and models that would be required to achieve this level of simulation accuracy over the larger Great Basin region.
1b.Approach (from AD-416)
The scientist funded through this project will work with university and ARS hydrologists to integrate the NWRC snow model into the PIHM system, and implement and evaluate the modified PIHM system at the RCEW. Located at the NWRC in Boise Idaho, the scientist would work collaboratively with the WATERS team to evaluate the accuracy and reliability of PIHM simulations using complete and successively limited RCEW forcing data. The 48-year data record will allow testing over a full range of climate conditions. Documents SCA with UC Santa Barbara.
During the past year ARS scientists at the Northwest Watershed Research Center (NWRC) in Boise, Idaho have been working to assess how climate warming is likely to impact water supplies in the western United States, and they have developed and tested a new and more effective approach to simulation modeling to improve how NWRC forecasts and manages water resources in the region. Significant progress was made in assessing the impacts of climate warming utilizing 50 years of very high quality data from Reynolds Creek Experimental Watershed. Initial tests of the hybrid Penn State Integrated Hydrologic Model (PIHM) and Isnobal model indicate that it can be effectively applied over mountain basins, and that it will improve assessment of water resources under a wide range of climate conditions. The ARS models of radiation transfer and snow cover energy balance were successfully applied to large regions of the Sierra Nevada. The jointly funded postdoctoral researcher assisted ARS in the development of two proposals that are currently pending. Research progress and status are reported via regular conferences calls, meetings and frequent email. The agreement was established in support of Objective 3 of the in-house project, the goal being to develop improved coupling of surface and belowground models for spatial simulation of snowmelt, runoff, soil temperature and moisture, and streamflow.