Jeff Masters Weather Blog

Atlanta’s population could boom as people flee sea level rise, wildfires, and hurricanes » Yale Climate Connections

“A climate-driven migration has already begun,” writes climate change journalist Abrahm Lustgarten in his must-read book, “On the Move: The Overheating Earth and the Uprooting of America,” which I reviewed in my previous post. And few places in the U.S. will likely see more climate migrants than Atlanta, which lies close to coastal areas of the Southeast U.S. where sea level rise can be expected to displace millions of people this century. Through the eyes of Jairo Garcia, former director of climate policy at the Mayor’s Office of Sustainability and Resilience, Lustgarten tells Atlanta’s climate change story.

a book cover that reads, "On the Move: The Overheating Earth and the Uprooting of America" a book cover that reads, "On the Move: The Overheating Earth and the Uprooting of America"

Many migrants are likely to choose Atlanta

Every city will face enormous climate-change-related challenges in the coming decades, and Atlanta has been more proactive than most U.S. cities at confronting climate change. However, the city is drastically unprepared to deal with both a changing climate and a huge increase in population, Lustgarten writes. By the 2040s, the Atlanta metro area could grow by 50%, from 5.8 million people to 9 million — even without the extra influx of people climate change migration might bring.

Past global climate-related migrations suggest that people prefer to change their lives as little as possible and stay as close to home as they can by moving to a nearby urban area. Lustgarten cites a 2017 study by Mathew Hauer of the University of Georgia, which predicted that over 320,000 climate refugees could be expected to move into Atlanta by 2100 from a hypothetical 1.8-meter sea level rise. The only U.S. cities likely to see more sea-level-rise-driven climate migrants are Austin, Texas (over 800,000 migrants) and Orlando, Florida (over 450,000).

But sea level rise won’t be the only driver of migration. People are also likely to flee to Atlanta to escape extreme heat, wildfires, drought, and hurricanes elsewhere. (The city absorbed tens of thousands of people in the wake of Hurricane Katrina in 2005).

Climate migration expert Hauer adds that his 2017 migration estimates are likely too low — they assume one person is added for each person that migrates. But in reality, family members will join the new residents, some arrivals will go on to have children, and an influx of service workers will come to support the new population. This could result in a factor of 5-18 increase in the number of people settling in the new city, according to Hauer’s as-yet unpublished research.

Side-by-side photos. On the left, a lake. On the right, a dried-up shoreline with a much smaller lakeSide-by-side photos. On the left, a lake. On the right, a dried-up shoreline with a much smaller lake
Figure 1. Two views of Lake Lanier, Georgia on March 4, 2007 (left) and February 11, 2008 (right) show the impact of the fierce drought that affected the Southeast U.S. in 2007-2008. (Image credit: Brian Hursey, CC by 2.0)

Atlanta’s water supply is inadequate for large population growth

Supplying water for all those new people will be a huge issue. Atlanta, unlike most major cities, developed around rail lines rather than a major body of water. Although the Chattahoochee River runs through Atlanta, the city lies on top of a watershed with no large bodies of water upstream. The rivers and streams in the region are small, and the bedrock limits how much groundwater is available. The Lake Lanier reservoir that supplies Atlanta with 70% of its water was constructed in the 1950s. Since that time, the population of Atlanta has more than quadrupled, increasing the pressure on the reservoir’s limited water.

To compound matters, both Florida and Alabama dispute Georgia’s water rights for two shared river basins, and the three states have been engaged in the “Tri-State Water Wars” since 1990. Though Georgia won a Supreme Court water rights case against Florida in 2021, litigation with Alabama is ongoing.

With the current average of seven days per year of heat above 95 degrees Fahrenheit predicted to increase by 10-20 days per year by 2050, water supplies in Atlanta will likely be severely stressed. According to the EPA, because irrigated farmland will need more water in the future hotter climate, the total demand for water in Georgia is likely to increase 10-50% during the next half-century. But the amount of available water is likely to decrease as soils become drier and drought intensity increases. According to the 2023 U.S. National Climate Assessment, longer-term droughts in the Southeast U.S. do not appear to be occurring more frequently but do appear to be increasing in severity.

Lake Lanier fell perilously low during a drought in 2007-2008. If the lake had completely run dry, Atlanta would have been left with only a three-day emergency supply of water. But thanks to the development of 53-acre Bellwood Quarry in 2020 as a new water reservoir for the city, Atlanta now has a 30-90 day emergency supply of water for the next serious drought.

The infrastructure isn’t ready

Atlanta’s stormwater drainage is troubled, Lustgarten writes, and the city lacks dedicated funding for improving it. The city’s public transportation and highways are inadequate, and the city “is not prepared to receive this number of climate immigrants,” Garcia says.

A huge amount of affordable housing will be needed to accommodate climate migrants. Although Atlanta has made good on its promises to build some affordable housing, the city has fallen well short of what is needed. The city has primarily chosen to emphasize economic growth, projects that “business leaders and real estate developers could get behind politically, the ones that were highly visible and made for great photographs, with new parks and trendy, slick urban landscapes,” Lustgarten writes.

Such developments have led to a tripling of home prices since 2012 in one neighborhood he visited. Gentrification and an increase in disparity between wealthy White areas surrounded by poor Black communities has made these areas “more vulnerable to heat and rising food insecurity, and cut off from transit as they are displaced.”

Inequality sets the stage for conflict

In the city’s predominantly Black Bankhead neighborhood, which is rapidly gentrifying, life expectancy is 24 years less than in a predominantly white and wealthier neighborhood just six miles away. In fact, Atlanta is one of the most unequal cities in America, and is a “virtual tinderbox for social conflict,” Lustgarten writes. One huge problem to address with a growing population will be food systems. “Atlanta’s poor neighborhoods have the least access to fresh produce and grocery stores of almost anywhere in the nation,” Lustgarten writes.

The complexities of the climate migration problems cities like Atlanta face “argue for strong, overarching and coordinated policies and leadership” in the U.S., with “creation of a new, cabinet-level climate czar working inside the White House,” Lustgarten writes. But one of the climate adaptation experts that he interviews, Jesse Keenan of Tulane University, cautions that the word “resilience” has become a sort of buzzword. When people talk about resilience, they are really talking about a large-scale effort to keep things the way they are. “They don’t realize what we really need to be talking about is not maintaining the status quo,” Keenan says, “but the true transformation of economies to make them more equitable and sustainable.”

Bob Henson contributed to this post.

We help millions of people understand climate change and what to do about it. Help us reach even more people like you.

Source link