A difference of just half a degree of global warming, from 1.5 to 2 degrees Celsius, would mean that an additional 5 million people worldwide will have the land where their homes are located be permanently submerged underwater, according to a new study published in the journal Environmental Research Letters.
The research, led by scientists at Princeton University, analyzed the global impacts on sea levels of 1.5 degrees C of warming, the current target of the Paris Agreement, compared to 2 and 2.5 degrees. It looked at data from tide gauges across the globe and created local sea level rise projections. The scientists examined what would happen to everyday sea levels, but also to extreme sea-level events, such as storm surges.
The study found that under a 1.5 degrees C scenario, global mean sea levels could increase 1.6 feet by 2100, 1.8 feet for 2 degrees of warming, and 1.9 feet for 2.5 degrees. It also found that if nations managed to limit warming to 1.5 degrees, extreme sea-level events could still be catastrophic for coastal communities. The New York City area, for example, could experience one Hurricane Sandy-like flood event every five years by the end of the century.
“People think the Paris Agreement is going to save us from harm from climate change,” the study’s lead author, DJ Rasmussen, a graduate student at Princeton, said in a statement. “But we show that even under the best-case climate policy being considered today, many places will still have to deal with rising seas and more frequent coastal floods.”
For more information on the difference between a 1.5 and 2 degree world, click here.