A new study that examines The physical and socioeconomic effects of sea level rise in the Miami-Dade County area of Florida reveal that in the coming decades, four in five residents may face disruption or displacement, whether or not they live in flood zones. As floods spread, the effects will be felt predominantly by low-income people as living areas shrink and house prices rise, the study says. Only a small number of wealthy residents will be able to relocate from low-lying or beachfront properties, while many others without sufficient means could be trapped there, he says.
The study has just been published in the journal. Environmental research letters.
“Most studies focus on the direct effects of flooding,” said lead author Nadia Seeteram, a postdoctoral researcher at Columbia University’s Lamont-Doherty Earth Observatory. “Here we were able to look at flooding at a very granular level and add other vulnerabilities.”
The study combines building-by-building projections of flooding caused by direct sea level rise, rainfall or storm surge with detailed demographic data to determine how residents will be affected. Along with flood maps, researchers used data from the U.S. Census Bureau to map economic and social factors that would make people more or less vulnerable, including age, race, education level, income and employment status, and whether they owned or rented their homes. , among other measures. They then divided the population into four categories.
With a one-meter rise in sea level (an intermediate scenario by the end of this century), 56 percent of the population, mainly on higher ground, could face pressure to relocate, they say. Researchers call these people “displaced.”
The next largest group they called the “trapped”: about 19 percent of the population, living in chronically flooded territory, but without the means to flee to safer ground nearby. According to the researchers, about another 19 percent would be “stable,” living in non-flood-prone areas and able to remain there. Only seven percent (basically the wealthiest, whom the researchers labeled “migratory”) would be directly exposed to flooding in coastal or low-lying areas, but could move to safer places within the metropolitan area.
Not surprisingly, the study says that if sea levels rise by even more than one meter, direct flooding, not economic pressures, will become the dominant force affecting residents. At two meters (quite high by the current range of estimates, but not out of the question), around 55 percent of the population will be directly flooded due to a combination of high sea level and, increasingly, rainfall. In this scenario, 49 percent of the population would be trapped and 25 percent displaced. Only eight percent would be classified as stable.
“This is where everything becomes more drastic, more existential,” said Seeteram, who conducted much of the research during his doctoral studies at Florida International University. In either scenario, he said, the results would include possible depopulation of the area and devaluation of flooded properties, as people flee to safer inland regions. This could make it increasingly difficult for officials to raise taxes to fund infrastructure adaptations to keep the ocean at bay, a circular process that could send Miami-Dade into an increasingly serious downward spiral, both physically and fiscally. .
The study does not analyze how many people are currently affected by the floods, either directly or indirectly. But flooding has already become a routine part of life, as monthly peak tides seep through sewers during so-called sunny day floods, and rain piles up on streets with nowhere to go. where to drain The type of flash flooding in New York City that made headlines after a major storm in late September would be seen as just another day in parts of Miami during the May-October rainy season, Seeteram said. An as-yet-unpublished survey by Seeteram and his colleagues indicates that nearly three-quarters of Miamians say they have been personally affected by rainfall-induced flooding in one form or another.
There are also some signs that so-called climate gentrification — the displacement of low-income people from higher elevation areas, as the study predicts — is already happening. For example, in recent years, the Little Haiti neighborhood, elevated at a relatively high 10 feet above sea level, has seen a surge in development and property values, worrying mostly black residents. that maybe they can’t stay.
Study co-author Katharine Mach of the University of Miami said there is “a big, heated debate” about whether climate gentrification is underway. “I suspect it’s already happening,” she said. However, she said, at least for now, other factors may be playing a bigger role in the rapid shift in real estate values, including long-standing pro-development policies and what she calls “real estate tourism,” in which Speculators buy relatively cheap properties in a region that is still booming. “The question is: what fraction (of the price increase) can be attributed to the weather?” she said. She noted that real estate prices are also rising in low-lying and coastal areas, but not as quickly as in less flood-prone areas, a possible indicator that projected sea level rise is influencing buyers’ decisions.
Seteeram said the new study’s projections may not necessarily come to pass, at least with lower estimates of sea level rise; It depends on how the metropolitan area deals with the problems in the coming years. Renovating infrastructure to reduce flooding and taking other measures could mitigate the effects, he said. “We could see different types of housing development, to make the population denser in some areas or more climate resilient. But then you would have to see what the intersection would be with affordability for a lot of people.”
The study’s other authors are Kevin Ash of the University of Florida, Gainesville, and Brett Sanders and Jochen Schubert of the University of California, Irvine.
– This press release was originally published in the Columbia Climate School Website