Rising sea levels could displace 6mn Americans, researchers claim

Researchers claim millions of Americans face potential displacement due to disproportionate rises in sea levels. That’s putting most of the US coastline in an increasingly vulnerable position, a new report says.

“The questions are when, and how much, rather than if,” the report from the National Oceanic and Atmospheric Association (NOAA) said. Using six scenarios from low to extreme, the report outlined possible environmental outcomes to prepare local, regional and federal agencies.

The best-case scenario saw a rise in global sea-levels of 1ft (30 cm) by 2100, with the worst-case seeing a rise of 8.2 feet (2.5 meters). Almost all scenarios saw all of the US coastline, except Alaska, see a rise of more than the global average.

Rising levels do not occur evenly around the globe, one of the report’s authors, William Sweet, told CBS. “In some scenarios sea levels in the Pacific Northwest are expected to rise slower than the global average, but in the Northeast they are expected to rise faster,” he said, warning that a rise of 6 feet would be enough to displace 6 million Americans.

The latest findings represent an update of a 2012 report, which predicted a worst-case rise of 6.6 feet, 1.6 feet less than the new report. Fueling the increased prediction is global warming, with 2016 being the third year in a row to set record high temperatures that saw polar ice melt to a new low.

“Even if society sharply reduces emissions in the coming decades, sea level will most likely continue to rise for centuries,” the report warned. Sweet said the projections are to allow “a coastal manager in Miami and one in Mobile, Alabama” assess the potential threats to their respective areas and plan accordingly.

Average sea levels have around the world have increased by an estimated 8 inches (21cm) to 9.5 inches (24cm) since 1880, 8cm of which have occurred since 1993, according to a 2015 report.

One of the report’s co-authors, the Environmental Protection Agency (EPA), were this week issued a gag order preventing them from talking to the media, as well as awarding grants or publishing research.

READ MORE: Trump bars EPA & USDA from talking to media or awarding grants

Trump’s nominee to lead the EPA under his administration, Scott Pruitt, said at his confirmation hearing that the impact of humans on climate change is “subject to continuing debate and dialogue.”