National-scale estimates of forest ecosystem carbon pools and fluxes are crucial to comprehensive carbon cycle accounting.  In the U.S., forest ecosystem and product carbon fluxes provide one of the largest offsets of annual greenhouse gas emissions.  Current estimates of forest ecosystem and product pools and fluxes for the U.S. were developed by the USDA Forest Service under the framework of the Montreal Process Working Group on Criteria and Indicators in order to evaluate the sustainability of forest ecosystem processes that mitigate greenhouse gas emissions. 

Results/Conclusions

Results of this national assessment indicate that forest ecosystem carbon pools still provide one of the largest offsets of greenhouse gas emissions.  However, in the context of national-scale forest health issues such as fire, land-use change, and invasive species, the direction of carbon fluxes in the future is in question.  In light of possible climate change effects, trends in national-scale forest ecosystem carbon pools and fluxes may contain even greater uncertainty into the future.