If only we could go back in time some 500 years to ask Giorgione the meaning of this painting. Of course, there are theories about who the man and woman are, which city we see and the symbolism of the thunderstorm and the two broken columns. But they are just that: theories and not one of them is definitive.
To complicate things: Xray analysis has shown that where the man stands Giorgione had previously sketched another nude woman. It would have been a different painting altogether if he had left her there.
But would having a clear meaning make The Tempest more beautiful or make us appreciate it more?