Since long before Ponce de León stumbled upon Florida, humans have called Palm Beach County home. In fact, human occupation of the County goes back at least 6,000 years—to a time before the Egyptian Pyramids were built.

Evidence for this occupation is scattered around the state, with at least 380 known archaeological sites in the County. Local scientists and archaeologists are dedicated to documenting these ancient people and learning more about how they lived. Many of these archaeological and historical sites are open to the public, and draw tourists from across the country; heritage tourism generated over $1.5 billion for the state of Florida in 2007, according to one study.

Unfortunately, as sea levels rise, the risks to the County's archeological sites increase. At least forty sites along the coast would be adversely affected by one foot of sea level rise, according to the County's Archeologist Christian Davenport. Increasing storm surges and increasingly heavy rainfall also threaten the sites. Water can not only damage human artifacts, but also shift sand and soil layers around, making it harder to determine their order and relationship. Unlike a building or road, many of these historical and archaeological artifacts are integrated into their location, and cannot be moved or raised. This means that researchers must hurry to document and study these sites before the changing climate overwhelms them.

This past summer, Lynn University archeologist Dr. April Watson and geologist Dr. Alanna Lecher, launched an archeological exploration at the County's South Inlet Park, on the barrier island just south of Boca Raton inlet. A 1970s study had already revealed ancient middens—piles of trash consisting mostly of discarded shells and animal bones—which indicated the presence of a beachside human settlement at the park's location thousands of years ago. 

Watson and Lecher set out to determine if this site, so close to the ocean and in such a public area, was still intact. The original site is only around 10 feet above sea level and a few hundred feet from the beach, leaving it vulnerable to heavy rainfall and storm surges. Luckily the scientists discovered that the park's sea wall and natural vegetation had protected the site since its discovery. Their excavations revealed a previously unrecorded midden layer, indicating human habitation of the area that may be even older than the known midden. However, the newly-discovered deeper midden is actually just below sea level, and therefore under much more threat from inundation.

Watson has a passion for educating the public about pre-Columbian history in Florida, and views that history as being at risk from the encroaching ocean and rains. These risks are not unique to this site: she notes that sustainability and resilience are currently general trends across archaeology.

Besides archaeological sustainability, Watson is also interested in interactions between human settlements and their environment. "These people had similar concerns to people living on the beach today—the stability of the islands, what to do about mosquitoes. They may have moved seasonally within the state to avoid hurricanes, or to find their favorite foods, making them the first paleo-snowbirds," she says.

According to preliminary results, early human habitation at the South Inlet Park site coincides with stabilization of the barrier island. This is unusual, because, as Lecher points out, barrier islands are usually unstable and can move up to "thirty feet in one hundred years." This presents the researchers with a "chicken and egg" problem: did humans move to the island because it stabilized, or did human presence cause the island to stabilize through the building of structures and discarding of waste which helped bind the sand together? More study of this site, and others like it in the Everglades, is needed to answer this question, according to the researchers. Knowing more about barrier island stability is crucial to those who live, work, and play on and around these islands today.

In 2010, Palm Beach County, along with Broward, Miami-Dade, and Monroe counties, formed the Southeast Florida Regional Climate Compact to coordinate climate change mitigation, adaptation, and research activities across county lines. The Compact's Unified Sea Level Rise Projection predicts sea-level rise beyond a 1992 baseline of up to 10 inches by 2030, 26 inches by 2060, and 61 inches by 2100.

Given that a moderate sea level rise of 12 inches would put so many of the County's archaeological resources at risk, the County hopes to continue archeological studies like Watson and Lecher's to capture the singular knowledge that each site provides before the site is destroyed. Currently Davenport and the Office of Resilience are collaborating on a mapping tool to identify, evaluate, and prioritize archeological sites threatened by climate change and sea level rise. Despite the threat to these historically and economically important locations, the County, in conjunction with local researchers, is working to document and preserve the sites wherever possible.