Authors: Rebecca Brice*, United States Geological Survey, Bethany Coulthard, University of Nevada, Las Vegas, Kevin Anchukaitis, University of Arizona, Inga Homfeld, University of Nevada, Las Vegas, Laura Dye, University of Nevada, Las Vegas
Topics: Paleoenvironmental Change
Keywords: dendrochronology, hydroclimatology, Fraser River, climate change
Session Type: Virtual Paper
Start / End Time: 11:10 AM / 12:25 PM
Room: Virtual 30
Presentation File: No File Uploaded
Dendrohydology has traditionally been applied in large semiarid watersheds with long concentration times, where water-year runoff is a scientifically feasible ⎯ and socially and ecologically meaningful ⎯ target for streamflow reconstruction. A new paradigm is converging in dendrohydrology, however, as climate change-attributed hydroclimatic shifts modify contributions to runoff in more complex river basins across western North America. This talk describes a case study and new approach to large, complex basin reconstruction. the Fraser River Basin, an ecologically and commercially critical watershed draining much of British Columbia, Canada. This unempounded and fast-draining system is experiencing both worsening spring floods and late summer droughts as a result of climate change, but its variable terrain and hydroclimate means this watershed cannot be reconstructed using traditional tree-ring methods. Here, we present a novel reconstruction approach that targets seasonal runoff and extremes (flood, drought) in a large watershed. Our preliminary results suggest that the natural (pre-instrumental) range of variability in flood and drought extremes surpasses instrumental data benchmarks currently used for Fraser Basin water management.