Climate change is increasing the average temperatures of North American forests. In the contiguous United States forests overall have experienced a 0.8 °C increase since 1900, and the Canadian boreal forest increased by 1.5 °C in the same period. There is evidence that some areas within the western boreal forest in British Columbia have increased by 2 °C since 1948, and there is a high likelihood that these regions will rise by another 3 or 4 degrees before the end of the century, thus permanently changing this ecosystem. As well, the health of the boreal forest is threatened not only by climate heating but also drying, which compounds problematic shifts in this northern-most forest type.
