What does the poem Apostrophe to the Ocean mean?

Apostrophe means to address something than cannot reply back.

Byron was born with a clubbed foot so he was naturally a good swimmer and loved the ocean. The poem is about his love for the ocean and how "man marks the earth with ruin" but his control stops with the ocean shore, man cannot control the ocean.

there is more to it, but i was looking for answers myself and thought I'd help out a bit here