Published May 31, 2019 at 11:04 AM | Updated at 7:32 PM PDT on Jun 1, 2019
A red tide turned San Diego's coastal waters a bright shade of blue this week. The phenomenon, created by phytoplankton through a process called bioluminescence, is unpredictable. But when photographers hear a red tide is occurring, they flock to the beach to catch a glimpse. Here are some photos they captured of bioluminescence on May 29 and 30 on shorelines from Solana Beach to Torrey Pines State Beach.