and other parts of the world.

California started one of the United States' first king tide programs, a collaboration between agencies and non-profit groups. "We wanted to give people a way to bring climate change home and see what it would look like," said Marina Psaros, a founder of the program. More than 20,000 people now receive the group's emails.

At a typical king tide event, volunteers are urged to fan out along a stretch of coastline and photograph impacts to beaches, roads and other locations. The photographs are then uploaded to a set of websites, or shared on Twitter or other social media.

As participation has increased, the resulting photographs are proving helpful to planners and flood-control agencies. According to Burger, South Carolina is using the photographs to gauge whetherking tide flooding was lower or higher than forecasts had predicted.

Yet protocols vary in archiving the photographs. Some images online include no information on time and location. In South Carolina, managers have developed a "MyCoast" app where photographs are time stamped with geolocation data.

Some science educators have quickly recognized king tides as a potential teaching tool. In South Carolina, teacher Merrie Koester launched a project for students at Charleston Development Academy to explore flooding in and around the charter school, due to king tides, storm runoff and nearby development replacing marshes.

The students ended up producing a hip-hop video about king tides and the flooding. They also collaborated on a public presentation, which included an explanation of what causes king tides.

"A king tide takes place at full or new