Why do i keep dreaming about tsunamis?

For a long time, I have had dreams that had tsunamis in them. I'm constantly running away from them, or trying to get people out of the way from them, and sometimes I get swept away by them. I feel the water hitting me roughly and the impact always hurts but I never end up dying in the dream. Whenever I get swept away though the dream just resets to where the tsunami first began. The tsunamis are huge and they tower over everything, very tall, menancing waves. Sometimes they block out the sun. They always move fast too towards me. Is there some sort of meaning behind them?