Thousands of historical and archaeological sites across the US are at risk from rising sea levels. In fact, according to a paper recently published in PLOS ONE, more than 13,000 recorded archaeological sites in the southeastern US could be submerged as early as 2100, assuming levels rise by a meter (3 feet). This includes over 1,000 that have been listed as important cultural properties on the National Register of Historic Places (NRHP).

These bleak statistics are based on heritage data from the Digital Index of North American Archaeology (DINAA), which aggregates archaeological and historical data across multiple sources. 

"Sea-level rise in the coming years will destroy vast numbers of archaeological sites, buildings, cemeteries, and cultural landscapes,” lead author David Anderson, from the University of Tennessee, said in a statement.

“Developing informatics capabilities at regional and continental scales like DINAA is essential if we are to effectively plan for, and help mitigate, this loss of human history."

While it's extremely difficult to predict exactly when and by how much sea levels will rise, the current statistics are not optimistic. The National Oceanic and Atmospheric Administration (NOAA) released a paper in January warning of an "extreme" scenario whereby global sea levels could rise by as much as 2.5 meters (8.2 feet) by 2100 – half a meter (1.6 feet) more than their 2012 previous estimate. If we're lucky, they say, levels will rise by only 0.3 meters (1 foot).

Anderson and his co-workers point out that the number of sites at risk will increase substantially with each additional meter rise. A 5-meter (16-foot) rise, say, would threaten more than 32,000 archaeological sites and 2,400 properties on the NRHP. While sea walls and other barriers could be installed to protect land from rising waters, these too could damage many of the country's recorded and undocumented cultural sites.

Some of the more iconic buildings, they predict, will be relocated to higher ground. This means Washington landmarks like the White House and Lincoln Memorial could be transported to a city further inland like Egyptian Abu Simbel temples were during the construction of the Aswan Dam in the 1960s. 

And it's not just buildings that could be forced to relocate. It's predicted that 13.1 million Americans will lose their homes by 2100 due to rising sea levels. Those living in southeastern states will be among the worst affected.

But now is not the time to resign ourselves to this fate, the researchers say.

"What we are hoping to get started is a conversation in American archaeology, and world archaeology," co-author Josh Wells from Indiana University told Wired.

"What are the effects of climate change on the record as we understand it, and to what extent do we need to triage and focus our efforts on recovering what we can before it's gone?”