Fast transient of Pulse Amplitude Modulated (PAM) fluorescence for La Jolla red tide, 2024-2025

A red tide developed off the coast of La Jolla, California, in October, 2024. Twice-weekly net tow samples from the Scripps Institution of Oceanography Pier were sampled (09/16/2024 - 07/10/2025 (mm/dd/yyyy)) for analysis of their fast transient OJIP (Origin, J-step, I-step, and P-step) fluorescence signature using pulse amplitude modulated (PAM) fluorometry. The P-step represents the maximum fluorescence yield (FM) where the photosystem II (PSII) acceptor pool is fully reduced, and is dogma for bioenergetic models of terrestrial plant photosynthesis. The red tide dinoflagellates examined here did not have a P-step. The data registered here are biophysical proof that some marine organisms do not fit the terrestrial plant dogma of photosynthesis.