P2C2: Multi-Century Streamflow Derived from Watershed Modeling and Tree-Ring Data

Board Of Regents, Nshe, Obo University Of Nevada, Reno, Reno NV

Investigators

Abstract

Funding is provided to test a new technique in an effort to quantify the effect of watershed topography, vegetation dynamics, natural disturbance, and land use changes on proxy-augmented stream-flow records. The technique combines hydrological parameters derived from tree-ring records coupled with a mechanistic model. The premise of the research is that dendrohydrologists have employed sophisticated regression techniques to extend runoff records, but this empirical approach cannot directly test the influence of watershed factors that alter stream-flow independent of climate. The researchers posit that such a new approach can help better define uncertainty in paleoclimate reconstructions because it employs tree-ring records to generate long time series of precipitation and possibly temperature which then can be used as input to a mechanistic watershed model to calculate stream-flow. The analysis will be conducted with data from the upper reaches of the Walker River on the boundary between the Sierra Nevada of California and the Great Basin of Nevada. The researchers have already generated a 2,300-year tree-ring record of water-year precipitation from the region and will use this time series as a basis for analysis. The broader impacts involve supporting an undergraduate and graduate student during the length of the project as well as providing a new methodology for using tree-ring data to assess hydroclimatic variability.