Climate Adaptation Partnerships in Semiarid North America

A combination of severe sustained drought and rapid urban population growth in semiarid North America has raised awareness regarding the vulnerability of water supplies. At the same time meetings and media are filled with reports of a changing climate and a litany of impacts attributed to anthropogenic climate change, such as early snowmelt, decreasing fraction of solid winter precipitation, longer growing seasons, and early spring streamflow pulse, to name but a few. Dwindling Colorado River reservoir levels, for example, provide one graphic example of a possible future in a warmer world. In response to these challenges, water managers are updating and enhancing periodic plans, and developing new plans and contingencies under the rubric of adaptation to climate variability and change. This presentation describes and contrasts two partnerships between researchers, operational agencies, and city governments that are in the process of collaborating on the development of climate adaptation plans.

One is a project entitled “Assessment of Climate Impacts on the Surface Water Resources for Central Arizona: Regional Downscaling and Associated Climate Change Scenario/Planning Efforts for the Salt River Project Watershed and Colorado River Basin.” It focuses on water supplies for metropolitan Phoenix, Arizona, and it directly involves partners at four water management agencies and two universities, in addition to a number of participants and consultants. Some key issues for Phoenix area water managers that are addressed in the project include characterization of uncertainties from a variety of sources – of which the most prominent is climate model projections – and the potential to use paleohydrologic reconstructions in sensitivity analyses and hydrological modeling. A second project, entitled “Moving Forward: Adaptation and Resilience to Climate Change, Drought, and Water Demand in the Urbanizing Southwestern United States and Northern Mexico,” carries the torch of multi-year efforts to engage, raise awareness, build capacity, and now collaborate with water managers in the binational U.S.-Mexico border region of Arizona and Sonora. As researchers enter the collaboration phase, concerns have shifted from conveyance of hydroclimate information to identification and implementation of pilot projects to address issues of urban and agricultural water sustainability in rapidly growing cities in northern Mexico. Issues of working in a binational context, sustaining information flows and research partnerships, and institutional and political constraints will be contrasted with the Phoenix partnership case study.