Step onto the gritty white sands of Puuhonua o Honaunau National Historical Park and you are stepping into another time.
A time when fierce Hawaiian warriors came to seek solace and lick their wounds in defeat. A time when noncombatants could flee the battles raging around them. A time when those who broke kapu, the sacred laws, could avoid their punishment, if only they reached the sanctuary in time.
No harm could come to those who made it to this sacred place of refuge.
But now, scientists say, the grounds of Puuhonua o Honaunau, along with another important cultural site, Koloko-Honokohau National Historical Park, face a danger of their own. A rising sea is lapping away at the centuries-old structures and seawalls at both sites.
The refuge is the best-preserved in Hawaii, say researchers with the Union of Concerned Scientists, which released a report today identifying the two West Hawaii sites as the sites most at risk in the state.
Puuhonua o Honaunau is protected by the Great Wall, a lava rock and stone structure that’s almost 1,000 feet long, 18 feet wide and towering 12 feet high. It’s more than 400 years old, but it’s already being damaged by storm surges and flooding, scientists say.
“It’s not like this is something completely in the future,” Adam Markham, director of climate impacts at UCS and report co-author, said in an interview Monday with Stephens Media Hawaii.
Markham said the Great Wall, Aleale Heiau temple site and parts of a historic trail have already been damaged by storm surge and flooding and sacred sites, seawalls and fish traps are endangered.
At Koloko-Honokohau, a coastal hazard analysis carried out for the National Park Service by scientists from Stanford University and the University of Hawaii identified the Kaloko fishpond, the Aiopio fish trap, and the Aimakapa fishpond as among the park’s historic features most at risk from coastal hazards. The Aimakapa fishpond was used to raise fish for the alii, or royal chiefs, and may be more than 600 years old.
The tides are nibbling away at the beachfront at a rate of 3 to 4 inches a year, the scientists said. They estimate that at the current rate of erosion, the Aimakapa fishpond could be breached by 2050 and the walls of the Aiopo fish trap could be completely submerged by the end of the century.
The rising sea level, coupled with ocean warming that puts more energy into waves and surges, poses significant danger to shoreline structures around the Hawaiian Islands, scientists say.
The UCS report, being released at a Capitol Hill briefing today in Washington, D.C., details risks at 30 sites across the United States. The UCS, based in Cambridge, Mass., began as a collaboration between students and faculty members at the Massachusetts Institute of Technology in 1969 and is now an alliance of more than 400,000 citizens and scientists.
The report follows a May 6 National Climate Assessment that scientists and the White House called the most detailed and U.S.-focused scientific report on global warming, according to The Associated Press. The 840-page report includes 3,096 footnotes referring to other mostly peer-reviewed research. It was written by more than 250 scientists and government officials, starting in 2012, and looks at regional and state-level effects of global warming, compared with recent reports from the United Nations that lumped all of North America together.
The Society for American Archaeology, a nonprofit dedicated to protecting the archaeological heritage of the Americas and the world, issued a statement today in conjunction with the UCS report release, calling for more attention to be paid to preserving endangered archaeological sites, marking the first time the organization has sought to draw public attention to the damage climate change is causing.
To slow the rate of change and give archaeologists, historic preservationists and land managers want more time to protect these sites, carbon emissions must be reduced, according to the report.
“Cutting carbon emissions significantly and quickly can slow the pace of sea level rise, limit the temperature increases, and slow the expansion of the wildfire season,” Angela Anderson, director of the Climate and Energy Program at UCS, said in a statement.
Markham said Hawaii Island has a significant climate change research resource right in its own backyard, atop Mauna Loa, where the National Oceanic and Atmospheric Administration maintains an observatory that has been documenting steadily rising atmospheric carbon dioxide levels since 1958.
He said the observatory registered a tipping point on March 9, 2013, when the daily mean concentrations of carbon dioxide in the atmosphere reached 400 parts per million.
The UCS is lobbying Congress to fund President Obama’s proposed Climate Resilience Fund, which could be used to help municipalities and businesses become more resilient to climate change.
“The fund could also be used to help protect and preserve the nation’s iconic and historical landmarks and irreplaceable archaeological treasures that are being destroyed by sea level rise, wildfire and flooding,” said Anderson.
Some fossil energy groups, conservative think tanks and Republican senators assailed the May 6 National Climate Assessment as “alarmist,” according to The Associated Press. Some see climate change as a political issue, rather than an environmental one.
“It doesn’t matter if you deny it or not,” noted Markham. “It’s going to affect all of us the same whether you deny it or not.”
Email Nancy Cook Lauer at email@example.com.