The talk will be a brief recounting of Diego Rivera's visits to San Francisco, which bookend the relatively short span of time he actually spent in the U.S. The talk will include little known anecdotes about the connections in the artist's world, material gleaned mainly from the Diego Rivera collection at City College of San Francisco's Rosenberg Library. Will Maynez is the Physics Department lab manager at the City College of San Francisco. Trained as a painter, he has spent the last 14 years investigating the college's Pan American Unity mural and Rivera's theme of the reconciliation of art and science.

CONFERENCE ON AMBIGUITY, UNCERTAINTY, AND CLIMATE CHANGE http://calclimate.wordpress.com Session 3: Ambiguity, the Precautionary Principle and Climate Change Speakers: Marcello Basili, Fulvio Fontini and John Quiggin Over the past decade, there has been considerable progress in the economic theory of ambiguity and ambiguity aversion, involving decisions where the decision maker does not know, or is uncertain about, the probabilities attached to various potential outcomes. This is an appropriate characterization of the current understanding of many facets of climate change science: the uncertainty is pervasive and profound, with many unknowns, and unknown unknowns, that cannot be characterized in terms of a conventional probability distribution. The conference explores the application of developments in the economic theory of ambiguity to climate change policy, including both mitigation policy (the reduction of greenhouse gas emissions) and adaptation policy (coping with the consequences of climate change). Some, but not all, of the fog of uncertainty will gradually dissipate over time, but meanwhile policy decisions have to be made now, whether for mitigation or adaptation. Climate change policy analysis needs to reflect not only the prevailing uncertainty and ambiguity, but also the anticipated future resolution of uncertainty and ambiguity. The challenge is to incorporate risk and risk aversion, ambiguity and ambiguity aversion, and learning, more adequately into the formulation of a framework for decision making on climate change policy. This is the central focus of the conference. To explore this issue, the conference brings some leading researchers on the economic theory of uncertainty and ambiguity and the economics of climate change together with some leading climate scientists and modelers. Some of the invitees have been asked to make formal presentations or provide formal comments; others invitees are expected to contribute to the discussion from the floor.