Hilton Head Island Packet
May 18, 2017
By Maggie Angst
More than 65,000 Beaufort County residents will be threatened by rising sea levels by the end of the century, but inland cities will not go unaffected, according to a new study.
“A lot of times we think of sea level rise just as coastal issue or challenge. But if people are forced to move, they have to go somewhere, and here we were looking at where people were likely to move,” said the study’s lead author, Mathew Hauer, who was doctoral student in the department of geography at the University of Georgia.
The study, which was published in the Nature Climate Change journal in March, looked at likely migration to and from every U.S. county and metropolitan area in the face of a sea level rise scenario of 1.8 meters, or nearly six feet, by the year 2100.
The study is the first attempt to model the destination of millions of potentially displaced migrants from coastal communities using 2100 population forecasts for 319 U.S. coastal counties.
Previous impact assessments use current population figures without considering projected growth to assess long-term effects of coastal flooding, Hauer said.
“(Researchers) don’t typically look at population growth in coastal areas, which we know are consistently one of fastest growing areas in the country,” Hauer said. “When that growth is compounded over a very long time, there could be a very large difference (in the number of residents effected).”
Based on 2100 population forecasts, Hauer and his team reported that a 6-foot sea level rise will expose more than 13 million people in the U.S. to flooding and other hazards from rising seas.
Hauer examined the effects in two scenarios — if city and policymakers make no adaptation to rising seas such as sea walls and other fortifications vs. if they do use adaptations to mitigate migration.
According to the study, the Hilton Head-Bluffton-Beaufort metro area stands to see a net loss of about 65,000 residents if no adaptation is made, putting it in 19th place nationwide for cities with the largest net loss.
If adaptations are made, the area still stands to lose 50,000 residents, the study found.
The Charleston-North Charleston metro area faces even worse losses with a net out-migration projected at nearly 75,000.
During the same time period, the Atlanta metro area stands to gain a quarter million residents, which is third highest net gain in the country behind the Austin and Orlando metro areas.
The Charlotte and Raleigh metro areas both stand to gain more than 100,000 residents.
Scientists believe worldwide sea levels could rise by 3 to 6 feet by 2100, according to the study.
In Beaufort County, a 3-foot sea level rise would expose nearly 10 percent of the population to coastal flooding by the end of the century if adaptive measures are not taken. A 6-foot sea level rise would expose 26 percent of the population to coastal flooding, according to the study.
Frank Knapp, head of the Beaufort/Port Royal Sea Level Rise Task Force (also President and CEO of the South Carolina Small Business Chamber of Commerce), said that findings like this are why he helped create the task force.
The task force started meeting in December 2015 and in the coming weeks, it will have a final report with recommended adaptations to be taken to combat the rising sea level.
“At three feet, we found that the City of Beaufort has a good opportunity for resiliency,” Knapp said. “But if it rises to six feet, that’s a different story, because (the research) paints a very bleak picture.”