Climate variability and its impacts on human activities and economic growth complicate water management decision-making. Water managers in arid regions such as western North America must consider variability when addressing climate-related risks and vulnerability that arise from exposure to weather extremes such as drought, floods, or cyclones, as well as from growing populations and increasing water demand.

This research is part of a bi-national effort to provide water users ranging from individual farmers and ranchers to municipal water providers with climate information that improves capacity to make critical water-management decisions amid shifting weather conditions, long-term climate variations, and changing social and economic conditions. We specifically address how users currently access and use climate information to make decisions about water use and allocation, as well as how to identify and improve access to potential alternative climate information sources. For the region of study, which is comprised of the southwestern United States and northwestern Mexico, water for urban and rural uses depends on the frequency, duration, and intensity of rainfall associated with tropical cyclones, the North American Monsoon, and winter precipitation. This study links vulnerability and institutional analyses to identify where climate and economic considerations intersect within water supply and allocation decision-making strategies, and how climate information may be provided to better suit users' needs in order to improve their ability to effectively manage water resources.

A major achievement has been the development and publication of the first issue of the quarterly bi-national and bilingual Border Climate Summary (BCS). The BCS compiles recent climate conditions as well as seasonal climate forecasts for the Mexico-United States border region, including precipitation, temperature, drought, and El Niño conditions. Data are produced by national agencies such as NOAA's Climate Prediction Center and the Servicio Meteorológico Nacional in Mexico; climate outlook information are then interpreted and explained in the BCS. The publication was tested at a meeting of regional stakeholders involving municipal and rural water managers to see if the information provided was clear, understandable, and useful for decision-making. Repeated future iterations of this type of interaction will shape the BCS into a product that meets the needs of a spectrum of climate information users in the border region.