An unimaginable 2 billion people could become displaced from their homes by 2100 due to climate change-related rising ocean levels.
That would be about one-fifth of the world’s population at that time, and account for those who live near coastlines, according to new Cornell University research.
“We’re going to have more people on less land and sooner than we think,” the study’s lead author, Charles Geisler, said in a statement. “The future rise in global mean sea level probably won’t be gradual, yet few policy makers are taking stock of the significant barriers to entry that coastal climate refugees, like other refugees, will encounter when they migrate to higher ground.”
By 2100, Earth’s rising population is expected to reach 11 billion, according to the United Nations. As oceans swell from melting sea ice and coastlines are pushed inland, the sea water will ruin fertile land, making it more difficult for nations to feed that many people. And landmass available to live on will be diminished.
The researchers at Cornell estimate that these issues, exacerbated by climate change, will create 1.4 billion refugees by 2060. Geisler said that number could reach 2 billion by 2100.
He admits that these predictions are based on the worst case scenario. “We project what will happen if the entire low elevation coastal zone is lost due to swollen oceans — swelling caused by more melt water (glaciers and ice sheets) and warmer oceans,” Geisler told the Daily News. “That’s where the 1.4 billion becomes relevant. Permanent flooding of the low elevation coastal zone means land 10 meters above mean sea level would be lost to ocean encroachment.
“This is a sobering possibility, as it exceeds most estimates of what could happen within a century or two…Sea level changes and the climate forces behind them aren’t going to be linear, slow, or predictable. Ocean tides and currents themselves are changing; together with ever-stronger storm systems, they spell inland surge effects such as we have seldom seen.”
By collecting climate and demographic research, such as a 2015 study that cites, “mean sea levels could rise by one meter or more by 2100,” Geisler came to the astounding figure of 2 billion displaced people. The 2015 study also said that by 2060, about 1.4 billion people living in coastal areas would be at risk of losing their homes to the sea. These numbers are up from a 2009 estimate — based on older understandings of population growth and the effects of climate change — which concluded that up to 350 million people could be displaced by 2050.
In places like Florida — the second largest coastline in the U.S., state and local officials have planned for a “coastal exodus,” Geisler said, and other places like China need to begin anticipating weather-induced population shifts that drive people inland. Those moves will drive up greenhouse gasses that are already escalating global warming.
Low-elevation coastal zones also need to prepare for the storm surges associated with climate change.
Geisler and his team believe that land conflicts — caused by displaced people struggling to find places to live — could lead to the selling of public land and spaces for human settlement.
“The pressure is on us to contain greenhouse gas emissions at present levels,” he said. “It’s the best ‘future proofing’ against climate change, sea level rise and the catastrophic consequences likely to play out on coasts, as well as inland in the future.”
Refugees resulting from climate change were already an issue this past April in the Dominican Republic, where the Ozama River flooded during a storm, forcing people to permanently abandon their homes.
And in Virginia, despite President Trump’s call “not to worry,” scientists are giving Tangier Island about 20 years before it’s under water.