Potential Vegetation Cover 2041-2070 (FS) with BCC-CSM1-1-M RCP 4.5, 4km

The dynamic global vegetation model (DGVM) MC2 used monthly climate data and soil characteristics to simulate vegetation cover, carbon pools and fluxes, water fluxes as well as fire occurrence and effects. The DGVM was run on the NASA Earth Exchange (NEX) platform at 4km resolution.
 
Historical climate (1895-2011) was provided by the PRISM group at Oregon State University (Daly et al. 2008). Climate futures (2012-2100) were provided by University of Idaho colleagues who downloaded twenty climate model (see attachment for list of models) results from the Coupled Model Intercomparison Project  (CMIP5, http://cmip-pcmdi.llnl.gov/cmip5/) for representative concentration pathways (RCP) 8.5 and 4.5 (Moss et al. 2010, van Vuuren et. al 2011). Climate data were downscaled at U. of Idaho using the Multivariate Adaptive Constructed Analogs (MACA) approach (Abatzoglou 2011) over the western US.

Representative Concentration Pathways define emissions trajectory and associated radiative forcing. Radiative forcing is the change in the net (downward minus upward) radiative flux (expressed in Watts per square meter or W m-2) at the top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide (CO2) or the output of the Sun.

RCP8.5 represents the 90th percentile of the reference anthropogenic emissions range generating a radiative forcing of 8.5 W m-2 by 2100. RCP 4.5 is a stabilization scenario that assumes climate policies, in this instance the introduction of a set of global greenhouse gas emissions prices, will cause a decrease in anthropogenic emissions, resulting in lower greenhouse gases concentrations and consequently lower radiative forcing. With RCP 4.5 radiative forcing stabilizes at 4.5 W m-2 (approximately 650 ppm CO2-equivalent) by 2100.

We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP (Climate Model Intercomparison Project), and the climate modeling groups for producing and making available their model output. For CMIP, the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals.
 
Funding for this research was provided by the U.S. Department of the Interior via the Northwest Climate Science Center through agreement #G12AC20495 within the framework of the research project entitled "Integrated Scenarios of climate, hydrology and vegetation for the Northwest", P. Mote (Oregon State U.) principal investigator (http://bit.ly/104rQiB).