Journal Article climate change 059QF0KO0R Research Support, Non-U.S. Gov't Water boreal forest drought North American forest Research Support, U.S. Gov't, Non-P.H.S. Scots pine Soil boosted regression tree analysis buffering effect climate sensitivity cumulative stress eastern Canadian forests ecological modelling ecological thresholds evapotranspiration forecasting forest ecology forest mortality long-term inventory multi-model overstory and understory trees permafrost permanent plots permanent sample plot phenology rapid warming