Scientific Symposium Presentation Abstracts
September 19
Dr. Anthony C. Janetos: Where Will Ecosystems Go?
Climate-induced changes in ecosystems have been both modeled and documented extensively over the past fifteen to twenty years. Those changes occur in the context of many other stresses and interacting factors, but it is clear that many, if not most, ecosystems are sensitive to changing climate.
Changes in ecosystems can be manifest in their underlying physical or biogeochemical processes, and in the distribution and abundance of their constituent species. Both types of changes have been seen to date in both the historical and paleo-climate records, and both types of changes appear in models. Results of such models and observations are briefly summarized for the US and North America. The importance of disturbances such as fire and pest outbreaks is emphasized, as these appear now to be extremely important in recently observed events, such as pine bark beetle outbreaks in the Pacific Northwest.
The human consequences of changes in ecosystems can range from direct economic effects, to more indirect effects on ecosystem services. Each is important to understand, and a framework is presented for analyzing such changes from both scientific and policy perspectives. Finally, the importance of thresholds, rapid changes, and potentially irreversible changes is noted and documented, and the likelihood of such changes occurring as a result of climate change is explored.
