The North American Coordinated Regional Climate Downscaling Experiment (NA-CORDEX) is the North American branch of the international CORDEX effort. CORDEX initially grew out of a call by the World Climate Research Programme (WCRP) 15 years ago (2009) for greater coordination across downscaling activities, following the success of several previous regional climate modeling programs. Building on its precursor project, the North American Regional Climate Change Assessment Program (NARCCAP), NA-CORDEX has achieved significant advancements in dynamical downscaling, improved climate projections, and deepened our understanding of structural uncertainties resulting from ensemble design and downscaling. It has also substantially increased knowledge of regional climate processes and climate change across North America. Standardized protocols, coordinated modeling efforts, and user-focused accessibility features have played a critical role in these advances. NA-CORDEX has supported assessments of climate change impacts on resource management, agriculture, ecosystems, urban areas, water resources, and more, and contributed to international climate assessments (e.g., the IPCC AR6 report).

NA-CORDEX has made notable strides in advancing regional climate science. Continued collaborative efforts will further enhance our understanding of regional climate dynamics and their environmental and societal impacts, promising even greater insights into future climate scenarios.

This presentation will provide an overview of NA-CORDEX's historical development, exemplar key advances, dataset applications, lessons learned, and possible strategies to address ongoing and future challenges facing the effort.