Climate change is expected to impact vegetation in the western United States, leading to shifts in dominant Plant Functional Types (PFTs) and carbon storage. This study used a biogeographic model integrated with a biogeochemical model to predict changes in dominant PFTs by 2070–2100. Results show that under the Representative Concentration Pathway (RCP) 4.5 scenario, 40% of originally forested areas will transition to shrubland (7%) or grassland (32%), while under RCP 8.5, 58% will shift to shrubland (18%) or grassland (40%). These shifts result in a net loss in carbon storage (−60 gigagram of carbon under RCP 4.5 and −82 gigagram of carbon under RCP 8.5). Findings highlight the need to mitigate climate change's effects on vegetation and carbon storage.

Jared M. Kodero, Benjamin S. Felzer, Yuning Shi