Climate change is expected to induce significant changes in species’ geographical ranges. In order to predict the extent of these range shifts, we need to develop an understanding of species’ climatic limits. Statistical tools known as climate envelope models allow ecologists to correlate a species’ presence or abundance to climatic factors which allow us to forecast a species’ future geographic range based on climate projections. In this poster, I present forecasts from climate envelope models developed for dominant conifer tree species at Mount Rainier National Park in Washington State, USA.
The climate data used to create these models came from the PRISM climate model which interpolates climate variables across a landscape by combining climate station data, digital topographic maps, and known elevation-climate relationships. The data on tree species ranges comes from a survey of the forest community at Mount Rainier National Park that included 463 plots, each 250-1000m2 large, located throughout the Park’s forests. The data includes the size (diameter at breast height) and species of all tree species over 140cm tall within the plot.
Results/Conclusions
These trees play an important role in the community dynamics and ecosystem functioning of landscapes across the Pacific Northwest, and shifts in their ranges will have strong repercussions for many natural resources in the region. Results show that ranges are indeed expected to shift under warming scenarios predicted for the 21st century, with all species projected to move significantly higher in elevation. Species differed in their relationships between climatic variables and presence/absence. Thus, forest composition is expected to change with global warming. Future studies will incorporate dispersal and demographic data that allow us to estimate how fast these species will migrate in response to climate change, which in turn will enable us to predict whether populations of Pacific Northwest conifers will be able to keep up with a changing climate.
