Maps of forest species-climate profiles were developed to help predict how forests, plant communities, and species may change on the landscape in response to climate change. Each species map depicts a ‘viability score’, which is an index on the interval zero to one that indicates how consistent the climate at a location is with the contemporary occurrence of a species. A low score at a given point in time or space indicates that the species does not occur (or very rarely occurs) in climates like those depicted at that location.
These maps provide information on where suitable future climate may be located for specific tree species under different climate scenarios.
A key challenge for resource and land managers is predicting the consequences of climate warming on streamflow and water resources. Over the last century in the western US, significant reductions in snowpack and earlier snowmelt have led to an increase in the fraction of annual streamflow during winter, and a decline in the summer. This study explores the relative roles of snowpack accumulation and melt, and landscape characteristics or 'drainage efficiency', in influencing streamflow. An analysis of streamflow during 1950-2010 for 81 watersheds across the western US indicates that summer streamflows in watersheds that drain slowly from deep groundwater and receive precipitation as snow are most sensitive to climate warming. During the spring, however, watersheds that drain rapidly and receive precipitation as snow are most sensitive to climate warming. Our results indicate that not all trends in the western US are associated with changes in snowpack dynamics; we observe declining streamflow in late fall and winter in rain-dominated watersheds as well. These empirical findings have implications for how streamflow sensitivity to warming is interpreted across broad regions.