Treeline forests of white spruce in the southern Brooks Range, Alaska

The climate of Alaska has warmed rapidly since the early 1900s.  My research in Alaska investigates how the rapid warming in the last 100 years has affected the boreal forest.  Working with the Bonanza Creek LTER, I am continuing to monitor long-term study plots at treeline in order to document treeline advance, and am collaborating with Dr. Chris Fastie to use tree rings to investigate the impacts and history of insect defoliators (like aspen leaf miners, see photo below) in interior Alaska.  Follow this link to read about that research.

Aspen leaf miner damage on an aspen leaf, June 2010

Climate change is affecting the boreal forest in measurable ways– trees are beginning to colonize areas that were previously too cold, for example.  Other effects are more subtle, and harder to see.  I use tree rings to examine those subtler effects, looking at how tree growth changes with climate.  In a collaborative NSF-funded project, we are exploring how changes in the timing and amount of summer precipitation may affect the boreal forest– in essence testing the hypothesis that the boreal forest, although cold, is inherently a water-limited, semi-arid ecosystem.  You can read more about that research by following this link.

A steep, south-facing river bluff along the Tanana River floodplain in interior Alaska supports scattered spruce trees in an arid sagebrush steppe community.