The City of Huntington Beach does not allow drone takeoffs/landings on the beach. So I launched from the bluffs which are about 30-feet above the beach. This makes judging the height of the drone above the water very difficult using VLOS alone. If I was allowed to control the drone from the beach level, it would have been much easier to judge the height above the waves.
Another factor contributing to my
MA2's demise (besides my own carelessness) was that in my live view, the apparent drone height above sea level varied as the waves rolled in. Just before a large wave would come in, the sea level dropped making the drone appear higher than it actually was. Basically I learned that when flying close to the ocean's surface it's difficult to judge true height, using VLOS or FPV.
BTW, if anyone knows a good rule of thumb to ascertain (through the live camera view) if your drone is above or below an approaching obstacle, I'd love to hear it!