King tides arrive: How experts and Bay Area residents are taking part in research

"The ocean takes center stage during the king tides, predicted to arrive on the California coast this Wednesday through Friday, and then again Dec. 4-6 and Jan. 1-3. Waters climb to their highest point of the year, flooding some Bay Area beaches, stairways and streets before plunging to their lowest, exposing stretches of sand and reef usually hidden. The spectacle draws photographers, beachgoers and scientists alike, because beyond the beauty, king tides reveal how the coast is changing."

"Tides are familiar to anyone who spends time by the sea. Simply put, Tides are bulges of water that the Earth rotates under, says Serena B. Lee, a physical oceanographer at California Polytechnic State University. King tides are the extreme version, occurring only a few times a year when the sun, moon and earth align, intensifying gravitational pull and driving water higher than usual. For researchers like Lee, these events are golden opportunities."

"Although tides are predictable, they remain under-monitored along much of the California coast, including Santa Cruz. Lee and her team are developing low-cost tidal gauges to track water levels in these gaps, especially during king tides, when extreme highs mirror the levels scientists expect to see more often with future sea-level rise. The best time to plant an orchard was 30 years ago. The second best time is now, and that's the same with collecting data, Lee says."

King tides occur a few times yearly when the sun, moon and Earth align, producing the highest and lowest water levels that flood beaches, stairways and streets and expose sand and reef. They offer visual and measurable evidence of coastal change and mirror sea-level rise extremes expected in the future. Along much of the California coast, tides remain under-monitored, prompting development of low-cost tidal gauges to track water levels during king tides. At UC Santa Cruz's Center for Coastal Climate Resilience, webcams, machine learning and 3D modeling are used to map daily beach shifts and expanding intertidal zones during these events.

Read at www.santacruzsentinel.com