Current Research


Fraser River Basin Extreme Events & Salmon

In collaboration with the Fraser Basin Council and Province of BC (FLNRORD), we are developing a long-term probabilistic assessments of extreme events (flood, drought) on the Fraser Basin main stem and its sub-basins and how these affect Pacific salmon. In each basin, we target seasons most important for the resilience of in-stream ecosystems and salmon. Becky Brice (postdoc) and  Inga Homfeld (MS) are leading these projects, including the development of 35 new tree-ring proxy records from across the province.


Cascade Range Snow Droughts in HUC 6 Watersheds 

We are reconstructing annually-resolved historical snowpack dynamics at HUC 6 watershed scale for the Cascade Range, USA, to better understand how future snow droughts will influence watershed dynamics. These reconstructions capitalize on earlywood tree-ring measurements for tree species limited by the very deep snowpacks of the North Pacific cordilleras. Laura Dye (MS) is leading this project.

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Cowichan Watershed Streamflow Risk Assessment for Forest & Fisheries Management

In collaboration with Cowichan Watershed Board, we are reconstructing multi-century historical drought and precipitation records to probabilistically assess future risk of multi-year droughts during salmon spawning season in the watershed, using total ring width, earlywood, and latewood measurements from Garry Oak trees. 


Southern British Columbia Snow Droughts

We have developed the first high-resolution  300-year tree-ring based record of past snowpack dynamics for the cordilleras of southern British Columbia, using energy-limited tree-ring chronologies. These dataset will be freely-available for use by scientists, resource managers, and decision-makers.


Drought Assessment for Greater Victoria BC Water Supply (Sooke watershed)

We are developing paleorecords of drought for the Greater Victoria British Columbia water supply (Sooke watershed) to probabilistically asses the risk of future supply deficits under climate change. This is also the first use of coast Douglas-fir tree-ring records for paleodrought reconstruction.


Rio Grande Streamflow Reconstruction

We have developed an unprecedented 2000-year reconstruction of snow and snow meltwater for the Upper Rio Grande, New Mexico, USA, based on tree-rings. We are currently using this record to analyze water-management relevant characteristics of past and future snowpack decline in the basin.

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Western North American Gridded Snowpack Reconstructions

In collaboration with the U.S. Geological Survey Climate Science Centers, we have developed watershed-scale gridded 4x4 km spatial field records of annual snowmelt spanning western North America over the past 2000 years, from a large network of 1500 tree ring chronologies. These data products will be freely available via web platform. We are also developing an R package for downscaling watershed-scale snow from general circulation models (GCMs), and combining tree-ring data with reanalysis, data assimilation, and proxy-system modeling to validate and incorporate snowmelt in last millennium models and GCMs for the first time

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Snow droughts in the Greater Yellowstone Ecosystem

Two important questions for water managers, ecosystems, and communities are: “how many years can snow droughts last?” and “how often do multi-year snow droughts happen?” We answer these questions over time and space using tree ring based gridded snowpack reconstructions for the Greater Yellowstone Ecosystem.  

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Tree-ring pitfalls in the age of open-data

Tree-ring chronologies have become a foundational worldwide source of ecological and climatological information that is now used across the environmental sciences, but accurately using tree-ring chronologies requires a deep understanding of the methods applied to produce them and the limits those methods impose. This research highlights the most important constraints to consider when using publicly available tree-ring chronologies and offers recommendations for avoiding common pitfalls.


Arrow Canyon Dam Sedimentation Rate

As part of a restoration project in collaboration with the US Geological Survey Nevada Water Sciences Center and Bureau of Land Management, we are using dendrochronology to date the sedimentation rate Arrow Canyon Dam in the Arrow Canyon Wilderness.


Las Vegas Groundwater Supply

We are using ponderosa pine and Douglas-fir tree-ring records to reconstruct snowpack dynamics for the Spring Mountains, NV. These snow meltwaters are the primary source waters for the Las Vegas aquifer, the region's backup water supply and an important part of the local Mojave Desert ecology.