Scientists analyzed 540 urban areas that encompassed approximately 250 million inhabitants in the United States and Canada. For each urban area, they mapped the similarity between that city’s future climate expected by the 2080s and contemporary climate in the western hemisphere north of the equator using 12 measures of climate, including minimum and maximum temperature and precipitation during the four seasons.

The study also mapped climate differences under two emission trajectories: unmitigated emissions (RCP8.5), the scenario most in line with what might be expected given current policies and the speed of global action, and mitigated emissions (RCP4.5), which assumes policies are put in place to limit emissions, such as the Paris Agreement.

Climate-analog mapping is a statistical technique that matches the expected future climate at one location—your city of residence, for instance—with the current climate of another familiar location to provide a place-based understanding of climate change. Combining climate mapping with the interactive web application provides a powerful tool to communicate how climate change may impact the lives of a large portion of the population of the United States and Canada.

The paper, “Contemporary climatic analogs for 540 North American urban areas in the late 21st century,” by Matt Fitzpatrick of the University of Maryland Center for Environmental Science and Robert Dunn of North Carolina State University, was published in Nature Communications in February 2019.