Forests in the Eastern United States are changing in response to ecological succession, or variations in species and community structure over time, tree harvest, as well as other disturbances. Climate change has the potential to further impact these forests. A team of Northeast CSC supported researchers predicted the distribution and abundance of common tree species across portions of the Eastern U.S. under alternative climate scenarios of warming by the end of the century. Using a forest landscape change model, they forecast changes in tree abundances and distribution in the North Atlantic region of the U.S. while accounting for climate change, succession, and harvest. In addition, they compared multiple forecasts for the Central Hardwood, Central Appalachian, Mid-Atlantic, and New England regions of the U.S. to determine the level of agreement among different modeling approaches.

Forecasts for the North Atlantic region indicated tree abundances were affected primarily by succession and harvest, and secondarily by climate. Predictions showed an increase in Southern and Central Hardwood species and a decrease in Northern Hardwood and spruce-fir forest species under warming climates over the next 300 years. Agreement across different modeling approaches and different climate scenarios provided strong evidence of potentially important changes to forests in response to climate change. For example, the models were in agreement of decreases in northern species such as black spruce, balsam fir, northern white cedar, and red spruce; while, loblolly pine and some oaks and hickories were predicted to increase. Results are intended to guide decisions about forest management under climate change to maximize beneficial ecosystem services.

(This work is) “…extremely valuable for informing forest conservation decisions in the eastern U.S.  As someone who has directly used the results from this work as part of the New England Climate Change Response Framework, I can speak to how useful they are for integrating the influence of multiple drivers and processes when evaluating likely changes in the distribution of a given tree species.” - Tony D’Amato, University of Vermont

“The bottom line messages…are that forests are changing, that the extent and rate of change will vary by geography, that changes in some forest types will be broader in extent and more rapid than others, etc.” - Al Steel, U.S. Forest Service Scientist

The final report for “Changes in Forested Landscapes of the Northeastern U.S. Under Alternative Climate Scenarios” is now available on the project page.