Terrestrial

Increasing aridity as a result of climate change is expected to exacerbate tree mortality. Reducing forest basal area – the cross-sectional area of tree stems within a given ground area – can decrease tree competition, which may reduce drought-induced tree mortality. However, neither the magnitude of expected mortality increases, nor the potential effectiveness of basal area reduction, has been quantified in dryland forests such as those of the drought-prone Southwest US. We used thousands of repeatedly measured forest plots to show that unusually warm and dry conditions are related to high tree mortality rates and that mortality is positively related to basal area. Those relationships suggest that while increasing high temperature extremes forecasted by climate models may lead to elevated tree mortality during the 21st century, future tree mortality might be partly ameliorated by reducing stand basal area. This adaptive forest management strategy may provide a window of opportunity for forest managers and policy makers to guide forest transitions to species and/or genotypes more suited to future climates.

This climate change vulnerability assessment documents climate change impacts and trends that have been observed along the Kuskokwim River. It was commissioned by the Georgetown Tribal Council to help inform their efforts to re-settle the Native Village of Georgetown, and to provide a starting place for working with neighboring communities to plan for climate change. Information was collected through a variety of methods, including interviews with elders and the collection of Traditional Knowledge, mapping and graphing of environmental data, review of published literature, and interviews with local scientists and natural resource managers.