I could be wrong on this but I believe depending on the waves amplitude, if you are out deep enough you'd actually be safer on the water than on land. In this case I think it rolls under you like a really big swell The good news is there are a lot of places 100' above sea level really close to the shore in CA. If a tsunami were to hit say florida or louisiana, it would reach much further inland and destroy a much larger area. check out the graphic on this page and hit play.
http://science.howstuffworks.com/nat...s/tsunami3.htm
This is from the bottom of that page actually:
" tsunami's ability to maintain speed is directly influenced by the depth of the water. A tsunami moves faster in deeper water and slower in shallower water. So unlike a normal wave, the driving energy of a tsunami moves through the water as opposed to on top of it. Therefore, as a tsunami moves though deep water at hundreds of miles an hour, it is barely noticeable above the waterline. A tsunami is typically no more than 3 feet (1 meter) high until it gets close to shore."
In summary, the answer to tsunami safety is to never stop kayak fishing deep water.