San Francisco's waterfront (海滨) is on the National Register of Historic Places for good reason.
Its beautiful old landmarks, like the Ferry Building and the Bay Bridge, have been seen in many books, TV shows and movies—from the stories and novels of Jack London to the 1970s TV series The Streets of San Francisco. The future of San Francisco's waterfront, however, isn't safe.
In 2016, the National Trust for Historic Preservation put part of the city's shoreline on its list of the U. S. 's most endangered historic places, in part because of the threat of sea level rise. The waterfront landmarks of many cities are under increasing threat from floods and rising sea levels brought on by human-driven climate change. St. Mark's Basilica in Venice, Italy and the Venice Beach boardwalk in Los Angeles face similar challenges to San Francisco.
"The whole issue of climate change and historic preservation intersects (交织) right at the waterfront, " said Elaine Forbes, director of the Port of San Francisco. As she watched the boats come and go on a sunny afternoon, Forbes said, "Sea level rise hasn't historically been as much of a threat to San Francisco as major earthquakes. " However, that's changed. Parts of the main road that runs along the waterfront have flooded from heavy rains in recent years. The state estimates (预估) the water could rise up to about two and a half feet above its present level by 2060, and possibly up to seven feet by the turn of the century.
Now, San Francisco is considering measures to save its historic shoreline. But the growing magnitude and frequency of the climate-related threats, the high costs and effort needed in saving heritage sites, and competing ideas about what's worth saving and what isn't, can make it hard for cities to know what to do first.