EPA Dynamically Downscaled Ensemble (EDDE): Datasets for Adaptation and Resilience Planning for Environmental Endpoints

Abstract The EPA Dynamically Downscaled Ensemble (EDDE) is a collection of physics-based regional climate model output that projects the impacts of climate change across the United States to support strategic development, adaptation, and resilience planning for a sustainable future. EDDE consists of dynamically downscaled global climate model simulations for the twentieth and twenty-first centuries under various forcing scenarios. The U.S. Environmental Protection Agency began development of EDDE to quantify the effects of climate change on air quality and human health, which required a breadth of data that were not routinely archived or publicly available. EDDE uses the WRF Model to downscale global climate simulations over most of North America. Uniquely among regional climate datasets, the EDDE archive includes hourly, 3D data from continuous simulations of recent historical periods and future years through 2100. EDDE is suitable for exploring regional climate variability and change and its influence on extreme weather events across the United States to quantify potential impacts on environmental endpoints, such as air quality and human health, pollutant deposition to sensitive ecosystems, stormwater management, and phenological indicators important for agriculture. EDDE data were used in the Air Quality chapter of the Fourth National Climate Assessment (NCA4), and the next generation of EDDE is poised for broad use in NCA6. A subset of variables from EDDE is now freely available via the Amazon Web Services Open Data Project. This paper describes the history, evolution, applications, availability, and future of EDDE, alongside the evolving needs of regional climate datasets to support decision-making. Significance Statement The EPA Dynamically Downscaled Ensemble (EDDE) contains climate change projections under CMIP5 and CMIP6 scenarios for most of North America using continuous simulations out to 2100. EDDE is a rich dataset (with hourly 3D data available at 36- and 12-km grid spacing) that can be used to explore potential impacts from climate change on various environmental endpoints. EDDE data have already been used to explore the impacts on air quality, human health, agriculture, ecosystems, extreme heat and humidity, extreme precipitation, and stormwater management. EDDE data are currently accessible with free egress via Amazon Web Services.