Re: What would happen if the ocean's water decreased by half?

Before answer that question, another question has to be raised. Where is
the other half of the oceanic water? Water or any other mass cannot simply
be destroyed. Let's say, the other half becomes water vapor (whether the
atmosphere can hold that much water vapor is another question), then the
Earth would become extremely hot, because water vapor is just like carbon
dioxide, a green house gas. Also there would be a lot of precipitation and
consequently, flooding.

As to the marine life, most of them would die because if half of the water
were to be gone, salt concentration would double, which is not an
environment that marine life are used to.

This is an interesting question.