The arid lands controversy beginning in the late 19th century provides a unique perspective on the role that large scale climate assessments play in the policy process. Initially the climate of the western arid lands divided scientists, policy makers, and the public between those that believed new conditions would require specialized policies and adaptations and those that argued conditions would not be severe. The consensus eventually emerged for a large-scale response, a consensus based on the seminal Report on the Arid Lands of the United States and later scientific assessments that coupled the physical and human dimensions of climatic change. This earlier debate demonstrates how climate assessments in the United States play out in policy deliberations with public opinion and climatological events to ultimately control the fate of responses.
