Before September 2017, Dianiz Roman and Wilfredo Gonzalez hadn’t even considered leaving Aguadilla, the couple’s hometown in western Puerto Rico. But after Hurricane Maria hit that month, everything changed.

Both their workplaces, a funeral home and a gas station, were destroyed in a storm that killed an estimated 3,000 people and turned life on the island upside down.

“We struggled, trying to get supplies, water and food,” Gonzalez recalled in the months following the hurricane. There was nothing left to do, they say, but to try their luck thousands of miles north in Buffalo, New York, where Gonzalez’s sister had moved a year earlier.

Dianiz Roman and Wilfredo Gonzalez were not alone. In the wake of Hurricane Maria, thousands of people have fled the Caribbean island for western New York state, which is already home to a large Puerto Rican community.

As reports, immigrants tend to go to neighborhoods that meet their cultural and linguistic needs, but the immigrant exodus to Buffalo is not solely due to this community. Months before Maria hit, the city’s mayor declared Buffalo a “climate city,” noting that Buffalo has “… a tremendous opportunity as the climate changes.”

Since then, the city has released a relocation guide touting the advantages of living in Buffalo, including how the average July temperature is a comfortable 21 degrees Celsius. Also, in addition to Buffalo, planners in cities like Cleveland, Ohio, Michigan, Minnesota and others are beginning to map out what a future with more residents could—and should—look like.

What makes a city safe from climate change?

The issue of “climate havens” — places where extreme weather is rare and which tend to be in the northern US near fresh water — has gained traction in recent years as deadly wildfires, record heat and catastrophic hurricanes are increasingly affecting daily life in the southern and western parts of the country.

Last year, 675,000 people in the US were displaced by disasters. Many of the communities were once economically dependent on manufacturing and were able to meet the needs of an influx of immigrants: When factories began to close in the 1970s and residents moved elsewhere in search of work, they left behind homes and the city spaces that today they can be reused.

Cleveland, on the south shore of Lake Erie, has about 30,000 vacancies. Detroit, which has lost nearly two-thirds of its population since its industrial heyday in the 1950s, has more than 30 square miles of vacant land within its city limits. Duluth already has the infrastructure to accommodate tens of thousands of residents.

“We need to model various land use and development scenarios for population growth at the neighborhood, city, county and regional scales,” says Terry Schwarz, director of the Cleveland Urban Design Initiative. “But at this point, we’re just getting started.”

While available land may be an asset for some, other cities are looking at how to modernize existing housing stock by making it colder in the winter and warmer in the summer.

“Thinking through ways to revitalize the urban core will be central to having a more climate-resilient region,” says Nicholas Rajkovich of the University at Buffalo’s School of Architecture and Design.

A “climatic paradise”

While many Great Lakes cities have temperate climates and plenty of space, some believe that doesn’t necessarily translate into a “climate paradise” situation in the short term.

Other than the Puerto Rican hurricane survivors who migrated to Buffalo, there is little evidence that US climate migrants are already moving north. The populations of Cleveland, Duluth and Buffalo have remained largely stagnant over the past decade.

“We learned from our research that community resilience is just as important as infrastructure or natural resources in predicting how well a city can adapt to climate change or increased levels of immigration,” says Monica Haynes, director of Duluth’s Bureau of Business and Economic Research at the University of Minnesota Duluth.

Furthermore, these communities are not immune to climate change. “We’ve had a lot of days this summer with very poor air quality because of the wildfires in Canada. So saying that Duluth is ‘climate proof’ is not accurate,” adds Haynes. “Our city will experience negative effects from climate change.”

Buffalo USA

However, the seemingly unrelenting cycle of tragedies fueled by climate change continues to call into question which parts of the world will be sustainable in the coming decades.

Scientists say more intense, longer-lasting hurricanes and rising sea levels — about 13 million people in the southeastern U.S. could be displaced by the end of the century — are likely to change life in Florida and beyond . Some researchers believe that tornadoes are moving eastward into more densely populated areas of the South, possibly due to changing climate patterns. Wildfires are becoming a part of life in the West, and the recent devastation caused on the Hawaiian island of Maui shows the unpredictable nature of a changing climate.

Last September, another devastating storm, Hurricane Fiona, hit Puerto Rico, killing more than a dozen people, cutting power to millions and destroying crops.

But this time, Dianiz Roman and Wilfredo Gonzalez were nearly 2,000 miles north of the storm’s destruction.

After getting over the initial shock of the Buffalo winter, they say they’ve settled in well to their new life. Both work in the local school system and are part of a thriving Puerto Rican community clustered on Buffalo’s west side. “We don’t have the extreme heat that we have in Puerto Rico,” says Gonzalez. “It took a while, but I got used to the snow.”