Challenges and successes with incorporating CMIP6 climate data into EPA’s CREAT

Climate change impacts pose both an immediate and long-term threat to the continuity of wastewater, stormwater, and drinking water (water sector) utility operations and water supplies. To help utilities reduce the risks associated with climate-related hazards, the Environmental Protection Agency’s (EPA) Creating Resilient Water Utilities (CRWU) initiative provides a collaborative technical assistance program, online tools, and trainings designed to educate the water sector on climate science and adaptation options.

EPA uses the Climate Resilience Evaluation and Awareness Tool (CREAT) to assist water utilities in preparing for potential future climate scenarios. CREAT was one of the first adaptation tools available to water, wastewater and stormwater utilities to conduct climate change risk assessments and develop adaptation plans using the results.

The climate scenarios in CREAT are based on projected temperature and precipitation data, presented as warm-wet, neutral, and hot-dry scenarios based on GCM historical performance. EPA is currently updating these scenarios with data from the CMIP6 downscaled product, LOCAv2. Variables such as change in average annual temperature and precipitation, change in 100-year storm, and change in extreme temperature (number of days >100°F) are also calculated from the LOCAv2 ensemble.

This talk will present the methods used for scenario selection and calculations of extreme and average temperature and precipitation. Particular focus will be on the challenges overcome in presenting these large datasets within CREAT in a format that is most beneficial and usable for stakeholders and water utilities.