Jon Lawhead (University of Southern California) Title:MultiScale Modeling and Pluralism in Climate Systems The global climate is a paradigmatic complex system, and so exhibits interesting behavioral regularities at many different spatiotemporal scales. Moreover, these patterns are mutually constraining: the presence of a stable behavioral regularity at one scale can influence the structure of stable behavioral regularities at other scales. This structure of interscale constraints makes the construction of holistic climate models an unusually daunting scientific challenge. In this paper , I describe some of the novel conceptual and methodological challenges associated with modeling the behavior of complex systems, and consider how those challenges bear on the debate about pluralism in climate models. I argue that the burgeoning pluralism of climate models is a natural consequence of the global climate’s considerable complexity, and ought to be embraced as a boon to our attempt to accurately predict the future of Earth’s climate.