Climate Change May Trigger Broad Shifts in North America's Pacific Coastal Rainforests

Abstract Climate change poses significant threats to Pacific coastal rainforests of North America. Land managers currently lack a coordinated climate change adaptation approach with which to prepare the region's globally outstanding biodiversity for accelerating change. We provided analyses intended to inform coordinated adaptation for eight focal rainforest tree species of commercial importance and broad rainforest communities. By using two different approaches to determine vulnerability, including climate envelope modeling (Maxent) and the MC1 dynamic vegetation model, we were able to assess where Pacific coastal rainforests might be more stable over time. We examined vegetation stability based on climate projections and used protected areas and intact late-seral forest data to determine priority areas and current level of protections. Based on model outputs, focal rainforest conifers and general rainforest communities are more likely to persist and to expand their ranges along northern range margins while southern margins exhibited lower persistence and potential loss of suitable climate. Robust reserve design for temperate rainforests should include current and future late-seral forests as potential climate refugia to accommodate projected shifts in species of commercial and ecological importance.