How can climate change affect temperate forest tree ranges?

Climate change significantly impacts the distribution of temperate forest tree ranges by forcing species to migrate to remain within their suitable environmental niche. Because trees are sessile, they must rely on seed dispersal to colonize new areas as climates shift.12

Historically, during the rapid climatic fluctuations of the past two million years, tree species repeatedly migrated to track favorable conditions. Species that could disperse seeds over greater distances held a distinct advantage. Conversely, when migration was hindered by geographic barriers—such as mountains or seas—or when the distance required to traverse was too great, many species faced extinction.2

Today, the future of these forests depends on the genetic variability of tree populations, which provides the potential to adapt to new habitats or changing environmental conditions. However, the ability of a species to successfully shift its range is constrained by its specific physiological requirements, including temperature and moisture thresholds. If the rate of climate change exceeds a species' capacity to migrate or adapt, it risks local or regional extinction, similar to the historical loss of certain tree lineages in Europe.132