Though some may still deny it, climate change is having an effect on our lives . It’s making weather patterns more severe and unpredictable, and in some parts of the world, agricultural practices and natural ecosystems are collapsing. And in other places, it’s going to make things really expensive.

In vulnerable coastal cities like Miami, climate change and sea level rise threaten to drown low-lying lands. Not only will that displace people living in those areas, but it will make the remaining above-water lands more valuable, and more costly. This theory of “climate gentrification,” a term coined in 2013 by Jesse Keenan of Harvard’s Graduate School of Design, and investigated in-depth in a recent paper by Keenan, Thomas Hill, and Anurag Gumber, centers around a straightforward premise: “Climate change impacts arguably make some property more or less valuable by virtue of its capacity to accommodate a certain density of human settlement and its associated infrastructure.”

In other words, climate change will speed up the process of gentrification in coastal cities by constricting the supply of livable land, and rendering it very expensive due to scarcity. As that happens, lower-income people will struggle to remain in place. Keenan, Hill, and Gumber found ample evidence that this is already happening in Miami. The coastal city is seeing property values on high-elevation lands skyrocket, while once pricey waterfront property values are diminishing.

The most common reason this happens, Keenan says, is because real estate investors recognize the threat of climate change, and shift capital to more stable land and properties. In Miami, where higher-elevation properties were formerly more affordable (being farther from the beach)–and sites where people of color were often segregated–people are being priced out. Little Haiti, a historically lower-income Haitian neighborhood, sits about a mile back from the beach, on higher ground. Residents now are seeing investors eye their neighborhood with new interest–it remained relatively dry during the hurricanes Irma and Maria last year, and a smattering of new developments are going up. Slowly, longtime residents are beginning to feel they can no longer afford to live there, and are seeking someplace cheaper.

Residents of coastal properties are also feeling a squeeze: As climate risks to a property like flooding increase, costs for insurance and repairs go through the roof. And in places like Copenhagen, which have worked to retrofit their waterfront properties to be more resilient and developed green infrastructure that would mitigate the effects of events like flooding, these resiliency investments have raised the cost of living to the point where only wealthy people are able to afford to live there. “Even places that are really trying to do the right thing for people are making investments that have the unintended consequence of displacing the people they were trying to protect,” Keenan says.

This type of climate gentrification creates a ripple effect: As coastal dwellers defect for inland properties, they price residents of places like Little Haiti out. And those lower-income residents often find they have nowhere left to turn in their city, and are forced to leave for somewhere else. Keenan has actually found that in terms of net migration, Miami-Dade County’s domestic-born population has decreased every year for the past several years, which in the long-term, he says, will begin to reflect in the economy.

While climate change may be inevitable, its displacing effects do not have to be. There are a number of measures cities can take to ensure that their residents remain in place, and in conditions that are livable and affordable, as they adjust to the new realities brought about by rising sea levels and other environmental challenges.