people have flocked to cal state beach where the tsunami tide activity was especially dramatic. >> it just sucked way out like a superlow tide over the course of about five minutes and it's doing it again right now. this is the third one. could be the big one. >> this is the second time i've seen a tsunami here in santa cruz. when i was 13-year-old i saw the one in 1964 and it did exactly the same thing. the water retreated first. >> it was unbelievable to watch the sand shift, the mile buoy that's normally in one position is completely out of position right now. >> when they come into the shallow water here, all that energy moving the whole depth of the ocean gets piled up in the shallower water. the water shorten and actually get taller. >> so despite warnings and the possibility of more tsunami surge activity, there are surfers in the water at cal beach. after all, this is santa cruz and they're taking advantage of this. was a lifetime opportunity to ride a tsunami surf and that's the situation here in santa cruz. >> at that -- careenna, thank you very much. authorities are worried