Climate Change Study: Huge Changes in Weather for 450 US Cities by 2080

Bostonians are unfazed by snow; Seattle residents know how to handle rain; and heat is no object for your average Miami dweller. But as climate change threatens to reorganize the global climate, each city is going to have to start repping a new weather identity. An analysis released Tuesday in Nature Communications gives residents of each US city a good idea of what their actual weather might be like by 2080.

Led by Matthew Fitzpatrick, Ph.D., an associate professor at the University of Maryland Center for Environmental Science, and applied ecologist at North Carolina State University Robert Dunn, Ph.D., this study uses three climate datasets to estimate climate analogues for 540 urban areas in North America. In short, Fitzpatrick and Dunn took a city’s current climate, projected what that climate might be like in 2080, and compared it to a place on Earth today that has a similar climate. After analyzing 12 different variables across four seasons, the team estimates that the climate in any given North American location will be more similar to the climate of a place roughly 850 kilometers — 528 miles — south of it today.

“I lived in Knoxville, Tennessee, for four years, and so I am familiar with climates of the south,” Fitzpatrick tells Inverse. “And where I currently live, in Western Maryland, the climate is moving towards Southern Kentucky or Northern Tennessee. I feel like I moved out of Tennessee to get away from the climate and it’s following me up here.”

"“More broadly, we as humans have built a society in a certain climate state, and we’re now rapidly changing that climate state."

The data used in this analysis comes from the WorldClim dataset, and Fitzpatrick’s team used the climate data gleaned between 1960 and 1990 to map the current climate in each location, so these estimates may not factor in changes that happened since 1990. Still, he adds that it serves as a good baseline to measure how things will change going forward.

The analysis in the study is based on several different climate scenarios, each one geared towards understanding what climate will be like in 2080. One of the scenarios is somewhat optimistic: It models what climate would be like if policies to curb emissions are put into place and have a positive effect on climate by 2080. That’s referred to as the RCP4.5. The other scenario represents a darker situation — the climate if the world doesn’t curb emissions at all by 2080, called RCP8.5

Using the RCP4.5 scenario, they estimate that the climate in Washington, DC will feel like the current climate in Paragould, Arkansas. The climate in Los Angeles will be more similar to that of Las Palmas, Mexico (on the Baja Peninsula), and Portland, Oregon, will have weather similar to Lincoln, California (slightly north of the Bay Area). Fitzpatrick also designed a web app so anyone can check out what their hometown might feel like in 2080.

However, when the RCP8.5 scenario was applied, Fitzpatrick noticed that many urban locations in North America had no good modern-day comparisons. In the paper, they hazard a guess that the climate of DC will look like that of Greenwood, Mississippi, if we fail to curb emissions until 2080, but in the paper, they note that it’s not a great match. This, Fitzpatrick explains, raises the idea that urban climates could change so much by 2080 that it creates a situation he refers to as a “climate novelty.” He adds that climate novelty can range from a slight difference in seasonal distribution of precipitation to changes in rain and temperature that are unlike anything else seen in North America currently.

The idea that weather could become so novel in certain urban areas, like DC, raises new questions about how our urban societies can adapt to new climate challenges. Already, cities struggle to deal with strange climate aberrations. In 2014, a dusting of snow created chaos in Birmingham, Alabama, and a 2016 heat wave in Boston took its toll on college students. Fitzpatrick adds that cities will have to learn to adapt their infrastructure as these changes take shape.

“Depending on the severity of these changes, it could impact how well existing infrastructure can handle these climates,” he says. “Cooling demands could increase, or maybe there are changes in flood frequency that could have implications for storm water management.”

In short, he adds that something has to give when it comes to climate change. Even if emissions remain unchanged and the greater impacts of climate change on society aren’t addressed, the changes will come, and cities will have to rethink how to prepare themselves.

“More broadly, we as humans have built a society in a certain climate state, and we’re now rapidly changing that climate state,” Fitzpatrick adds. “So I think there are going to be a lot of changes related to that.”

Abstract: A major challenge in articulating human dimensions of climate change lies in translating global climate forecasts into impact assessments that are intuitive to the public. Climate-analog mapping involves matching the expected future climate at a location (e.g., a person’s city of residence) with current climate of another, potentially familiar, location - thereby providing a more relatable, place-based assessment of climate change. For 540 NorthAmerican urban areas, we used climate-analog mapping to identify the location that has a contemporary climate most similar to each urban area’s expected 2080’s climate. We show that climate of most urban areas will shift considerably and become either more akin to contemporary climates hundreds of kilometers away and mainly to the south or will have no modern equivalent. Combined with an interactive web application, we provide an intuitive means of raising public awareness of the implications of climate change for 250 million urban residents