Climate Change Impacts & Adaptations Speaker Series 2008/09 - Abrupt Climate Change: Would We See it Coming Early Enough?

Dr. Klaus Keller,  Department of Geosciences, Pennsylvania State University

Abstract: Model simulations and the geological record suggest that the Earth System can change abruptly and with little warning time in response to small and smooth forcing.  The potential collapse of the North Atlantic meridional overturning circulation (MOC) due to anthropogenic greenhouse gas emissions exemplifies such a climate threshold response.  Currently, the MOC sensitivity to anthropogenic forcing is deeply uncertain posing unique challenges to the design of climate risk management strategies. Here we analyze three questions. Would the currently implemented MOC observation system deliver an actionable early warning sign of MOC changes before the system has been committed to a threshold response? How could the MOC observation system be improved to deliver earlier and more precise warning signals? What are economically efficient risk management strategies in the face of uncertainty and learning about climate thresholds?

All welcome.