Dreaming that you are snorkeling, can be interpreted as symbolism of personality exploration. Snorkeling indicates your desire to understand the source of your emotions. You are exploring your feelings and by this exploration you are trying to understand why do you feel such emotions about certain things. Alternatively, snorkeling in the dream denotes your past experiences. Maybe you should look back at past feelings to understand better your current mental state. See what you can learn from those experiences.
Dream dictionary: snorkeling dream meanings
…If you were snorkeling in a dream, then it means that you are trying to figure out of who you are. The dream also shows the understanding of yourself you have. The dream might also represent the past, where the one remembers the things he has learned through that particular period of time….