Global warming threatens 30 of the nation’s cherished historic landmarks, including Mesa Verde, says a report released Tuesday by the Union of Concerned Scientists.
Wildfires, floods, melting ice and rising sea levels imperil national treasures of historical and cultural significance from coast to coast, the report says.
When Mesa Verde National Park was created in 1906, the greatest fear of preservationists was that artifacts and ruins of ancestral Puebloans would fall prey to pot hunters and vandals. They had no hint of the prolonged periods of drought that would aid and abet wildfires, which, in turn, cook the faces of rock carvings and hasten the sloughing off of the sandstone.
Slurry dropped by aerial firefighters in rugged terrain has stained and damaged sandstone. Red stains are particularly noticeable along the trail to Spruce Tree House, the third-largest cliff dwelling, the report says.
Wildfires also can turn porous soil into an impenetrable surface that speeds runoff to start erosion or undermine walls, the report says.
“A severe drought is plaguing the Southwest, and climate projections suggest more frequent and severe periods of drought in the region during the coming decades as a result of rising temperatures,” the report says.
“Compared to the averages for the twentieth century, precipitation was 4 percent lower, temperatures were 1.3 degrees (Fahrenheit) higher and stream flow – the most consistent indicator of drought – declined 16 percent over the first decade of the 2000s,” the report says.
Ongoing drought is weakening the regionally dominant piñon-juniper forests, making them more susceptible to wildfire and beetle infestations, the report says.
The toll taken on the historic landmarks could bring a decline in tourism, it says. Mesa Verde historically has attracted up to 500,000 visitors a year, visitors who contribute $47 million to the local economy.
Among other endangered historic landmarks are Bandelier National Monument in New Mexico, the Statue of Liberty, the Bering Land Bridge National Preserve in Alaska, the Cape Hatteras Lighthouse, the first English settlement at Jamestown, Virginia, and native Hawaiian structures on the Big Island.
The report says carbon emissions must be reduced to give archaeologists, preservationists and land managers time to protect the sites.
“Cutting carbon emissions significantly and quickly can slow the pace of sea-level rise, limit the temperature increases we know are coming and slow the expansion of the wildfire season,” the report says.