Coastal Risks Posed by Sea Level Rise and High Tides
King tides, which typically happen twice a year as a result of a gravitational alignment of the sun, moon, and
Earth, provide a preview of the risks rising sea levels may present along California coasts in the future. While king tides are
the extreme high tides today, with projected future sea level rise, this level of water and flooding will occur during regular
monthly high tides. During storms and future king tides, more coastal flooding and damage will occur. The King Tide Photo Initiative encourages the public to visually document the impact of rising waters on the California
coast, as exemplified during current king tide events. Photos show water levels along the Embarcadero in San Francisco,
California during relatively normal tides (top), and during an extreme high tide or “king tide” (bottom). (Photo
credit: Mark Johnsson).