The geographic pattern in potential forest productivity (bolewood production) under current conditions was initially mapped over Oregon and Washington (Latta et al. 2009) based on statistical relationships between site index of USDA Forest Service forest Inventory and Analysis plots and PRISM climate data (i.e. interpolated meteorological station data). SAR_current is the result of that analysis with potential productivity in terms of gC/m2/yr of bolewood production.Â
The same statistical relationships of climate to potential productivity were then used with downscaled climate data from General Circulation Models (800 m grid) to derive geographic patterns in potential forest productivity in 2100 (Latta et al. 2010).
The four climate scenarios were based on the IPCCs fourth assessment report and represent alternative future economic and environmental states of the world.
A1B = balanced energy sources, globalization, rapid economic growth, populations peaking mid-century then declining, and rapid introduction of advanced technologies (A1B_delta).
A2 = relatively slow economic growth and adoption of technological advances, population which continuously rises (A2_delta).
B1 = an environmentally sustainability focus with a shift toward an economy centered on service and information with the same population growth assumptions as in A1B (B1_delta).
COM = a future in which global CO2 emissions are held to year 2000 levels (COM_delta).
These changes in bolewood production are first order estimates that donât account for factors such as the effects of rising atmospheric CO2 concentration on photosynthesis and transpiration.