assuming that hydrogen is a mass produced energy source?

Question

what will happen to the ocean?

Answer 1

First hydrogen is not an "energy source" it is a way of storing and transporting energy for easy use, but is not a "source" because it requires almost as much energy to extract it as it produces. And if it does reach prominence the ocean will be unefected because the Hydrogen will be released (in a controled way) so that it will reunite with oxygen and once again form water which will eventanally reach the ocean. Also remeber every molecule of water has two atoms of hydrogen, and there is a lot of water in the ocean so even if it does remove water from the ocean there is plenty to go around.

Answer 2

The energy stored in the hydrogen contained in just 1 cubic mile of sea water would meet world energy demand for a week, and then it would recombine with oxygen and return to the sea.

So, it's no biggie. Good question!